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Curtis, Kyle. "The Application of Porous Concrete." The University of Arizona, 2016. http://hdl.handle.net/10150/623460.
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Sustainable Built Environments Senior Capstone ProjectThe southwest region of the United States is stressed for potable water and needs to positively utilize its current water resource. With the urban environment being mostly made up of concrete, it is now crucial to assess its development and application. The concrete used today is a mixture of cement, water and aggregates and is not permeable. The non-permeable property of common concrete prevents natural water absorption by the earth and greatly inhibits water to percolate back into the local water table. As concrete, has developed, porous concrete has been discovered. Porous concrete or pervious pavement is made in the same way that concrete is made with cement, aggregate, and water, but the aggregate used in porous concrete creates pores that allow water to pass through. By allowing water to pass through concrete, urban development will result in greater ground water recharge. As global warming intensifies weather patterns across the planet, Tucson, Arizona will experience heavier rainfall seasons. As the world’s climate changes, Tucson will experience heavier monsoon rain fall events. With heavier rain fall events urban flooding will become more of an issue. Grey infrastructure is needed to manage flooding caused by heavy rain fall. Porous concrete can be used as an effective way to manage storm water. This capstone has undertaken an extensive range of literature reviews to identify where porous concrete can be used for storm water harvesting. The literature reviews range from climate change to the benefits of storm water harvesting. Porous concrete allows storm water to infiltrate through it and back into the local aquifer and directs storm water into retention ponds for treatment and reuse. Porous concrete is a low impact development (LID) building material, which will turn urban development into Sustainable development. Porous concrete if used correctly for storm water harvesting can reduce potable water stress, reduce pollutants found in local waters, and reduce the strain on current storm drains. The required maintenance associated with porous concrete is minimal and not costly, therefore will be only briefly explained throughout this research. While porous concrete has a wide range of benefits ranging from water percolation to the reduction of the heat island effect, this paper will focus on its use as a means of storm water harvesting.
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Roberts, Ian David. "Droplet evaporation from porous surfaces." Thesis, University of Manchester, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.294978.
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Virgiliis, Afonso Luís Corrêa de. "Procedimentos de projeto e execução de pavimentos permeáveis visando retenção e amortecimento de picos de cheias." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/3/3138/tde-08092010-122549/.
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O trabalho tem por objetivo apresentar procedimentos de projeto e execução de obras de pavimentos permeáveis visando sua aplicação prática como medidas compensatórias de drenagem urbana com a finalidade de retenção e amortecimento de picos de enchentes em cidades densamente urbanizadas. Os procedimentos propostos se baseiam na experiência adquirida para a implementação de dois tipos de pavimentos permeáveis; um com revestimento constituído de blocos intertravados de concreto e outro com revestimento de concreto asfáltico poroso, conhecido como camada porosa de atrito. Para subsidiar o trabalho uma pista experimental foi construída como área de estacionamento nas dependências do Centro Tecnológico de Hidráulica CTH na Universidade de São Paulo onde foi realizado o experimento. O local do estacionamento atua como um reservatório subsuperficial de águas pluviais sendo que sua estrutura, constituída de agregados granulares, abriga no interior de seus vazios a água infiltrada pelas camadas do pavimento. Recomenda-se, após os estudos, que os procedimentos e seqüências de atividades de projeto e execução de obras de pavimentos permeáveis sejam contemplados pelo poder público e privado como solução alternativa em diferentes empreendimentos urbanos como grandes áreas públicas ou particulares, estacionamentos, parques, quadras esportivas, passeios, calçamentos e ruas de pouca solicitação de tráfego entre outros.The present work intents to show design and built procedures, of porous pavements; by paying attention on its practical appliances as compensatory option in urban drainage with purpose to retaining rainfall water by storage, reducing downstream flooding in cities with great urban density. The procedures here proposed are based in the know how acquired for the construction of two kinds of porous pavements: one built with interlocked concrete blocks and the other built with porous asphalt. In order to aid the present work, an experimental field was built as parking area inside the propriety of CTH Centro Tecnologico de Hidraulica in State University of Sao Paulo where the tests and experiments were made. The parking area is a reservoir structure where rain water is stored inside courses of aggregates. The storage volume is in the void space between particles of material that comes by infiltration trough the pavement layer. The commendation, after the studies, is that procedures and activities of design and build of porous pavements could be observed by government and private sector as alternative solution in many kinds of urban projects such as large public and private lots, parking areas sport fields side walks and streets, with low capacity of traffic loads, and so forth.
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Foster, Shiloh. "Porous Concrete: Proposal of UA Study and Best Practices." The University of Arizona, 2016. http://hdl.handle.net/10150/608602.
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Sustainable Built Environments Senior Capstone ProjectPorous concrete pavements have been used in the eastern United States to effectively manage storm water when used as an alternative to impervious surfaces. This paper reviewed a wide body of available literature and research to examine their potential to reduce runoff at the University of Arizona. This study found that their unique structural properties enable them to infiltrate and detain large volumes of water in a stone sub-base below the slab, filtering out many street related contaminants without the need to install additional infrastructure. Porous concrete surfaces may support green development in the southwest where water is both a sensitive and valuable resource. However, long-term structural durability, clogging potential due to dust, and maintenance requirements have yet to be fully understood in this region. This paper then summarizes critical factors that affect the performance of porous concrete and proposes a framework for future study to be conducted by the University of Arizona in a way that would reduce runoff to major campus roads, contribute to a better understanding of sustainable storm water management in the southwest, and demonstrate leadership in environmental stewardship.
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Goede, William Gunter. "Pervious concrete investigation into structural performance and evaluation of the applicability of existing thickness design methods /." Pullman, Wash. : Washington State University, 2009. http://www.dissertations.wsu.edu/Thesis/Fall2009/w_goede_112409.pdf.
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Thesis (M.S. in civil engineering)--Washington State University, December 2009.Title from PDF title page (viewed on Jan. 22, 2010). "Department of Civil and Environmental Engineering." Includes bibliographical references (p. 98-102).
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Mulligan, Ann Marie. "Attainable Compressive Strength of Pervious Concrete Paving Systems." Master's thesis, University of Central Florida, 2005. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2630.
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The pervious concrete system and its corresponding strength are as important as its permeability characteristics. The strength of the system not only relies on the compressive strength of the pervious concrete but also on the strength of the soil beneath it for support. Previous studies indicate that pervious concrete has lower compressive strength capabilities than conventional concrete and will only support light traffic loadings. This thesis investigated prior studies on the compressive strength on pervious concrete as it relates to water-cement ratio, aggregate-cement ratio, aggregate size, and compaction and compare those results with results obtained in laboratory experiments conducted on samples of pervious concrete cylinders created for this purpose. The loadings and types of vehicles these systems can withstand will also be examined as well as the design of appropriate thickness levels for the pavement. Since voids are supposed to reduce the strength of concrete 1% for every 5% voids(Klieger, 2003), the goal is to find a balance between water, aggregate, and cement in order to increase strength and permeability, two characteristics which tend to counteract one another. In this study, also determined are appropriate traffic loads and volumes so that the pervious concrete is able to maintain its structural integrity. The end result of this research will be a recommendation as to the water-cement ratio, the aggregate-cement ratio, aggregate size, and compaction necessary to maximize compressive strength without having detrimental effects on the permeability of the pervious concrete system. This research confirms that pervious concrete does in fact provide a lower compressive strength than that of conventional concrete; compressive strengths in acceptable mixtures only reached 1700 psi. Extremely high permeability rates were achieved in most all mixtures regardless of the compressive strength. Analysis of traffic loadings reinforce the fact that pervious concrete cannot be subjected to large numbers of heavy vehicle loadings over time although pervious concrete would be able to sustain low volumes of heavy loads if designed properly. Calculations of pavement thickness levels indicate these levels are dependent on the compressive strength of the concrete, the quality of the subgrade beneath the pavement, as well as vehicle volumes and loadings.M.S.C.E.
Department of Civil and Environmental Engineering
Engineering and Computer Science
Civil Engineering
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Aguirre, B., M. Anchiraico, J. Rodríguez, and F. García. "Sustainable urban pavement for cities affected by El Niño using porous concrete." IOP Publishing Ltd, 2021. http://hdl.handle.net/10757/655955.
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The El Niño phenomenon is caused by the change in atmospheric pressures, which produce the accumulation of hot surface waters on the eastern flank of the Pacific Ocean; causing intense rainfall that runs over the surface affecting the urban drainage of the city due to the lack of a permeable pavement; porous concrete allows infiltration of surface water runoff through its pores. The present investigation evaluates porous concrete in the range of w/c relationships of 0.30 and 0.32; the results indicate that the compressive strength, flexural strength and permeability coefficient increase; and that the surface runoff, cost, water footprint and carbon footprint are lower than conventional concrete.
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Hade, James D. "Determining the runoff coefficient for compressed concrete unit pavements in situ." Virtual Press, 1987. http://liblink.bsu.edu/uhtbin/catkey/483966.
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Roads and parking lots make up the largest percentage of manmade impervious surfaces in the world. Large amounts of runoff contribute to wastewater treatment plant overloads and subsequent raw sewage discharges. A high runoff rate reduces the groundwater recharge potential, causes stream bed erosion, and flooding which frequently results in the loss of life, property and /or crop damage. High runoff rates also cause surface pollutants to be washed into storm sewers, streams and other waterways, causing damage to aquatic plant and animal life. Pourous pavements are one of the tools which environmental engineers, landscape architects and planners may use in design for stormwater management to help reduce runoff.Previous investigators have assumed that compressed concrete block unit pavements, on a sand bed and gravel base, with sand joints, become impermeable over time. This study sought to determine the runoff coefficient for a trafficked pavement that has been in use for ten months. A Variable Intensity Portable Rain Simulator was used in 120 tests on nine plots from a pedestrian plaza and three plots from an intersection of a neighborhood outlet and a city street, paved with Unidecor (or Cobble-) Pavers. Three rainfall intensity ranges were tested for each pavement type; 0 to 7 millimeters per hour, 7 to 15 millimeters per hour, and 15 to 30 millimeters per hour. For storms with an intensity level of twelve millimeters per hour average, the runoff coefficient on the plaza was significantly different than that for the intersection. Additionally, it was found that for the three intensity ranges tested the runoff was significantly different for each range.Ball State UniversityMuncie, IN 47306
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Dry, Carolyn. "Design of systems for time delayed activated internal release of chemicals in concrete from porous fibers, aggregates of prills, to improve durability /." This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-05222007-091330/.
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Neithalath, Narayanan. "Development and characterization of acoustically efficient cementitious materials." Skokie, Ill. : Portland Cement Association, 2004. http://www.cement.org/bookstore/profile.asp?itemid=SN2924.
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Sciumè, Giuseppe. "Thermo-hygro-chemo-mechanical model of concrete at early ages and its extension to tumor growth numerical analysis." Phd thesis, École normale supérieure de Cachan - ENS Cachan, 2013. http://tel.archives-ouvertes.fr/tel-00907395.
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The aim of the PhD thesis has been the development of two multi-physics models based on common theoretical basis, but applied to two very different areas: i) the study of the behavior of concrete at early age, essentially for the prevention of early cracking and related issues- ii) the analysis of physical, chemical and biological processes that govern growth and development of cancer. The development of a numerical tool to model concrete at early age is of great importance for the design of durable and sustainable structures. The model has been implemented on the finite element code CAST3M (developed by CEA), also it was validated and nowadays allows multiple applications: study of stresses and cracking phenomena in young concrete, thermal and hygral gradients, autogenous and drying shrinkage, inhibition of hydration caused by drying, creep, stress redistribution, study repairs, etc.. In the fight against cancer, it is clear that the advance of medical strategies based on numerical analysis have a critical scientific interest and can have a great social impact. The equations which govern the thermo-hydro-chemo-mechanical behavior of concrete at early age have may formal analogies with those used to model tumor growth. Hence, these equations have been readapted and a novel mathematical model for tumor growth has been developed. The model was implemented in Cast3M and the first numerical results have been encouraging since very close to the experimental data present in the literature.
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Spence, Joshua. "PERVIOUS CONCRETE: A HYDROLOGIC ANALYSIS FOR STORMWATER MANAGEMENT CREDIT." Master's thesis, University of Central Florida, 2006. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4176.
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Portland Cement pervious concrete's ability to permit water infiltration has encouraged its use as a stormwater management tool. However, the material has suffered historically poor support due to a number of factors, including failures due to poor mix design and improper construction techniques, concern about lesser structural strength, concern about poor long term performance due to clogging of surface pores and undefined credit for stormwater management. This study focuses on long term performances of pervious concrete parking lots and their stormwater management credit. Before stormwater management credit could be estimated, it was necessary to develop a testing device to gather information from existing pervious concrete parking lots currently in use. Eight parking lots were examined to determine the infiltration rates of the pervious concrete, as well as to verify the soil makeup beneath pavement. A total of 30 cores were extracted from pervious concrete parking lots and evaluated for infiltration rates. Three of the sites had a pervious concrete section that included a gravel reservoir. Infiltration rates were measured using the application of an embedded single-ring infiltrometer. In an attempt to provide an estimate of credit, a mass balance model was created to be used for simulation of the hydrologic and hydraulic function of pervious concrete sections. The purpose of the model is to predict runoff and recharge volumes for different rainfall conditions and hydraulic properties of the concrete and the soil. The field derived hydraulic data were used to simulate infiltration volumes and rainfall excess given a year of rainfall as used in a mass balance operated within a spreadsheet. The results can be used for assessing stormwater management credit.M.S.
Department of Civil and Environmental Engineering
Engineering and Computer Science
Civil Engineering
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Dry, Carolyn Minnetta. "Design of systems for time delayed activated internal release of chemicals in concrete from porous fibers, aggregates of prills, to improve durability." Diss., Virginia Tech, 1991. http://hdl.handle.net/10919/37870.
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Incorporation of chemicals into the internal matrix of cement or concrete, with later release occurring upon stimulation, alters the matrix parameters from those at the initial set. Permeability is reduced, for example, and therefore durability enhanced. The advantages of these designs would be the ability to reduce maintenance and repair costs in the initial building configuration and to delay the time of eventual repair. The components and the structure could take greater environmental abuse also.
Permeability is significantly reduced by release of a polymer from wax-coated porous fibers upon heating to temperature of polymerization. Freeze/thaw damage is somewhat reduced by the timed release of linseed oil or antifreeze from porous aggregates due to the freezing action itself. These example designs using timed release mostly gave improved durability performance when compared to conventional treatments for durability or environmental distress. Concerns that significant strength reduction would occur due to heating or fiber loading were shown to be unfounded by our test results; indeed, heating and fiber inclusion increased strength. An adequate amount of wetting of the samples could be obtained with 2.75% volume of fibers; however, above a 2.75% volume of fibers, fibers do reduce the strength. Results were analyzed by the method of comparing results in the samples with factors varied to results in samples without variable factors, that is, by comparing to the controls.
This research shows that timed internal release of chemicals into cement can be accomplished; it appears feasible and is potentially useful.
Long-term tests need to be performed on such factors as chloride ion intrusion/ corrosion tests. Filled fiber, aggregate or prill manufacture, storage, and placement need to be researched and assessed for cost. Design of components using only targeted areas for release in the component and the use of time released fibers in reinforced cement laminates should be evaluated.Ph. D.
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Morgenroth, Justin. "The Effect of Porous Concrete Paving on Underlying Soil Conditions and Growth of Platanus orientalis." Thesis, University of Canterbury. School of Forestry, 2010. http://hdl.handle.net/10092/5112.
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Urbanisation is characterised by mass migration of people to urban areas and conversion of land from rural to urban land uses. Changes in population dynamics have led to half the world’s population living in urban areas; in developed countries, urban dwellers account for three-quarters of the total population. Though populations have shifted from rural to urban areas, people continue to rely on their environment, and trees in particular, for tangible and intangible benefits alike. A great deal of factual and anecdotal knowledge supports the role of trees for ecological, social, and economic well-being. In spite of this, during urbanisation, previously vegetated land is converted to housing, roads, or utility corridors, all of which are necessary to support growing populations.
This thesis investigates tree growth in these modified urban landscapes, in particular, the effects of pavements on urban trees. Pavements are truly pervasive, covering more than half of all land in highly developed urban areas. Their durability and strength are of great importance to transportation, but large-scale soil sealing is not without consequence. Pavements affect the hydrologic cycle, soil and air temperature, and nutrient cycling. Because of their effect on the surrounding environment, pavements inherently affect remnant or planted trees. They are believed to negatively affect tree growth and survival, thereby compromising the ecological, social, and economic benefits otherwise derived from the urban forest.
In recent times, porous pavements have been increasingly installed in favour of impervious pavements. Porous pavements are perceived to be an environmentally-sound alternative to standard impervious pavements. This thesis begins by reviewing the literature concerning porous pavement’s effect on underlying soil and urban vegetation, thus illustrating the scarcity of empirical data describing the effect of porous pavement on tree growth. A greater understanding of porous pavement’s impact on the surrounding environment is needed, if its installation is to continue.
With this aim in mind, this thesis describes an experiment in Christchurch, New Zealand, which monitored the impacts of porous and impervious pavement on underlying soil conditions, and subsequent tree growth. The experiment comprised 50 Platanus orientalis trees planted in an augmented factorial design, which consisted of controls and four treatments. Trees were split evenly amongst plots, such that ten replicates existed per treatment. The pavement treatments measured 2.3m by 2.3m, and were based on the combination of pavement type (2 levels: porous, impervious) and pavement profile design (2 levels: +/- subbase compaction and gravel base). The resulting four treatments were impervious concrete pavement (IP), impervious concrete pavement with compacted subbase and gravel base (IP+), porous concrete pavement (PP), and porous concrete pavement with compacted subbase and gravel base (PP+). From December 2007 to March 2009, data were collected to determine the effect of these treatments on soil moisture, aeration, pH, and nutrient concentration. Final tree height, stem diameter, shoot and root biomass, and root distribution were also measured at the conclusion of the experiment.
Results of this experiment indicated that the effects of pavement porosity on soil moisture and aeration were dynamic, varying with season and soil depth. Increased soil moisture beneath porous pavements resulted from rapid infiltration following precipitation. This decreased the duration of plant stress resulting from drought. Relative to bare soil, paved plots had consistently greater soil moisture, likely because pavements reduced evaporation. The inclusion of a gravel base in the profile design limited capillary upflow, which resulted in lower soil moisture under pavements designed with a gravel base. Soil aeration was significantly lower beneath pavements relative to unpaved plots. This is likely related to greater soil moisture beneath pavements. Finally, soil pH increased beneath pavements, in particular beneath porous pavements.
Though all growth parameters increased for trees surrounded by porous, rather than impervious pavement, this occurred only in the absence of a compacted subgrade and gravel base. Evidently, the impact of the compacted subgrade superseded the impact of pavement porosity. Furthermore, root growth was relatively shallow beneath pavements, likely due to favourable soil moisture directly beneath pavements.
This research highlights (i) the dramatic effect of pavements on underlying soil conditions; (ii) that pavements do not inherently limit tree growth; (iii) that porous pavements can conditionally improve tree growth; and (iv) that soil compaction limits potential benefits resulting from porous pavements.
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Vasilic, Ksenija. "A Numerical Model for Self-Compacting Concrete Flow through Reinforced Sections: a Porous Medium Analogy." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-194402.
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This thesis addresses numerical simulations of self-compacting concrete (SCC) castings and suggests a novel modelling approach that treats reinforcement zones in a formwork as porous media. As a relatively new field in concrete technology, numerical simulations of fresh concrete flow can be a promising aid to optimise casting processes and to avoid on-site casting incidents by predicting the flow behaviour of concrete during the casting process. The simulations of fresh concrete flow generally involve complex mathematical modelling and time-consuming computations. In case of a casting prediction, the simulation time is additionally significantly increased because each reinforcement bar occurring in succession has to be considered one by one. This is particularly problematic when simulating SCC casting, since this type of concrete is typically used for heavily reinforced structural members. However, the wide use of numerical tools for casting prediction in practice is possible only if the tools are user-friendly and simulations are time-saving. In order to shorten simulation time and to come closer to a practical tool for casting prediction, instead to model steel bars one by one, this thesis suggests to model zones with arrays of steel bars as porous media. Consequently, one models the flow of SCC through a reinforcement zone as a free-surface flow of a non-Newtonian fluid, propagating through the medium. By defining characteristic parameters of the porous medium, the influence on the flow and the changed (apparent) behaviour of concrete in the porous matrix can be predicted. This enables modelling of any reinforcement network as a porous zone and thus significantly simplifies and fastens simulations of reinforced components’ castings. Within the thesis, a computational model for SCC flow through reinforced sections was developed. This model couples a fluid dynamics model for fresh concrete and the macroscopic approach for the influence of the porous medium (formed by the rebars) on the flow. The model is implemented into a Computational Fluid Dynamics software and validated on numerical and experimental studies, among which is a large-scale laboratory casting of a highly reinforced beam. The apparent rheology of concrete within the arrays of steel bars is studied and a methodology to determine unknown input parameters for the porous medium is suggested. Normative tables defining characteristic porous medium parameters as a function of the topology of the rebar zone for different reinforcement cases are generated. Finally, the major contribution of this work is the resulting numerical package, consisting of the numerical solver and the parameter library. The thesis concludes on the ability of the porous medium analogy technique to reliably predict the concrete casting behaviour, while being significantly easier to use and far less time consuming than existing toolsDie Arbeit behandelt die numerische Modellierung des Fließverhaltens von selbst-verdichtendem Beton (SVB) in bewehrten Schalungselementen. Die numerische Simulation des Fließens von Frischbeton kann eine vielversprechende Unterstützung bei der Optimierung von Befüllvorgängen sein, indem diese bereits im Vorfeld vorhergesagt werden. Die Simulation des Fließens von Frischbeton verwendet komplizierte mathematische Modelle und zeitintensive Rechenoperationen. Darüber hinaus wird die Simulationszeit für die Vorhersage des Füllvorgangs zusätzlich deutlich verlängert, weil aufeinanderfolgende Bewehrungsstäbe einzeln zu berücksichtigen sind. Das ist insbesondere für die Simulation von SVB ein entscheidendes Problemfeld, da SVB oft gerade für hochbewehrte Bauteile verwendet wird. Dennoch ist ein weitreichender Einsatz von numerischen Hilfsmitteln bei der Vorhersage von Füllprozessen nur denkbar, wenn die Anwenderfreundlichkeit und eine Zeitersparnis gewährleistet werden können. Um die Simulationszeit zu verkürzen und näher an eine anwenderfreundliche Lösung für die Vorhersage von Füllprozessen zu kommen, wird als Alternative zur einzelnen Modellierung aller Stahlstäbe in dieser Arbeit vorgeschlagen, Zonen mit Bewehrungsstäben als poröse Medien zu modellieren. Infolgedessen wird das Fließen von SVB durch bewehrte Zonen als Strömung eines nicht-Newton’schen Fluides durch ein poröses Medium betrachtet. Durch die Definition charakteristischer Parameter des porösen Mediums kann das veränderte Verhalten des Betons in der porösen Matrix vorhegesagt werden. Dies ermöglicht die Modellierung beliebiger Bewehrungszonen und vereinfacht und beschleunigt folglich die numerische Simulation bewehrter Bauteile. Im Rahmen der Arbeit wird ein Rechenmodell für das Fließverhalten von SVB durch bewehrte Schalungszonen entwickelt. Das Modell verkoppelt das Strömungsverhalten von Beton mit dem makroskopischen Ansatz für den Einfluss von porösen Medien, welche in diesem Fall die Bewehrungsstäbe ersetzen. Das entwickelte Modell wird in eine CFD-Software implementiert und anhand mehrerer numerischer und experimenteller Studien validiert, darunter auch ein maßstabsgetreues Fließexperiment eines hochbewehrten Balkens. Darüber hinaus wird die scheinbare Rheologie des Betons innerhalb der Anordnung der Stahlstäbe untersucht und daraus eine Methode zur Bestimmung unbekannter Parameter für das poröse Medium vorgeschlagen. Es werden hierfür auch normative Tabellen generiert, die die charakteristischen Eigenschaften der porösen Medien für unterschiedliche Bewehrungsanordnungen abbilden. Zuletzt ist der Hauptbeitrag dieser Arbeit das resultierende Numerikpaket, bestehend aus dem numerischen Solver einschließlich des implementierten Modells sowie der Parameterbibliothek. Im Abschluss werden die Verlässlichkeit der Vorhersage von Füllvorgängen durch die Analogie zu porösen Medien erörtert sowie Schlussfolgerungen zur deutlichen Ersparnis an Aufwand und Zeit gegenüber herkömmlichen Methoden vorgenommen
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Wang, Jin. "Modeling of concrete dehydration and multhiphase transfer in nuclear containment concrete wall during loss of cooling accident." Thesis, Toulouse 3, 2016. http://www.theses.fr/2016TOU30098/document.
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Les centrales nucléaires jouent un rôle important au niveau mondial dans la production d'électricité aujourd'hui. Dans l'histoire humaine, deux accidents tragiques ont déjà eu lieu, à Tchernobyl et Fukushima, provoquant des fuites des matières radioactives. Pour éviter ce genre d'accident dans la future, la construction en béton prend un rôle important en tant que matériau de construction de confinement qui est la dernière barrière pour isoler la matière radioactive de l'environnement. La compréhension des transferts dans le béton dans des circonstances graves, en particulier à étudier le comportement du béton sous haute température jusqu'à 200°C. Dans la première partie, un modèle de déshydratation a été appliqué dans le modèle thermo-hygro. Le modèle thermo-hygro a ensuite été mis en oeuvre pour simuler une maquette dont les résultats expérimentaux sont disponibles dans la littérature, sans tenir compte des comportements mécaniques. Enfin, des études paramétrique ont été réalisées pour étudier l'influence de certains paramètres. Le modèle à ensuite été appliqué à des structures sous vitesse de chauffage différente, et le modèle à ensuite été appliqué à des structure sous rythme de chauffage différents et celles avec des épaisseurs différentes pour comparer les profiles de température et de pression de gaz à travers de la murNuclear power plant now takes an important part in the world's electricity generation. In human history, there have already been two tragic accidents in Chernobyl and Fukushima causing severe radioactive matter leakage. To pre- vent this kind of accident from happening again, concrete structure plays an important role as material of containment building, which is the last barrier to isolate the radioactive matter from the environment. Hence, the transfer properties of concrete under severe circumstances, especially high tempera- ture, are important for this usage. This PhD thesis aims to investigate the behavior of the concrete under high temperature up to 200°C. In the first part, a dehydration model was proposed. The model consists of different dehydration sub-models for main hydrates in the cement paste. In the second part, the dehydration model was implemented in a thermo-hygral model. The thermo- hygral model was then used to simulate a mock-up for which experimental results are available in the literature, without considering the mechanical behaviors. At last, parametric studies were performed to investigate the influ- ence of some parameters, and the model was then applied to structures under different heating rates, and structures with different thicknesses to compare the temperature and gas pressure profiles across a wall
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Ndawula, Joanitta N. "Towards a triphasic Theory of Porous Media-based model for chloride-induced corrosion in reinforced concrete." Master's thesis, Faculty of Engineering and the Built Environment, 2019. http://hdl.handle.net/11427/31022.
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This thesis is concerned with the initial development of a multiphase material model using the Theory of Porous Media (TPM) for the penetration of intermediary rust product into reinforced concrete subjected to chloride-induced corrosion. Research has shown that although the majority of time-to-cracking service life models for reinforced concrete structures neglect the permeation of rust into the cement paste adjacent to the reinforcement, it is this mechanism that is responsible for discrepancies between experimental data and model results. The model presented may be used to simulate the transport of water and gas through the capillary pores in concrete and the diffusion of iron III chloride within the pore solution. Iron III chloride is a soluble chloride complex formed as an intermediary product during the oxidation reaction at the anode of the corrosion cell. This solute is transported in the pore solution from low oxygen conditions and is oxidized in oxygen-rich conditions resulting in the precipitation of rust in the concrete pores. The Theory of Porous Media has proven proficient for modelling the material behaviour of porous solid bodies saturated with one or more fluids but has yet to be applied to chloride-induced reinforcement corrosion of reinforced concrete. This work outlines the initial efforts of using TPM to model the rust transport process coupled with the poro-elastic material response of reinforced concrete. The latter accounts for the stress build-up due to rust precipitation and volume expansion. The chloride complex is described by a concentration within the liquid phase and is therefore not assigned a unique volume fraction. Precipitation of the rust is not included here as it will be added at a later stage in the development of a more accurate reinforced concrete chloride induced corrosion model. It is intended that the model thus developed may be adapted for other deterioration mechanisms in concrete.
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Chang, Yen-Ming, and 張晏銘. "Study of Porous Concrete." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/57087890276933888992.
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碩士國立中興大學
土木工程學系所
96
The purpose of this article are both to discuss the technique of mass production of porous concrete block and construction art of manufacture porous concrete in the field. Mixture or proportions was designed to use the concept of no-fine concrete which mainly comes from two sources, aggregate materials and binder materials. The difference of porous concrete to that of normal concrete is that binder materials is only attached to aggregate particles and not completely filled in between the pores of aggregate particles which constitute pores that are connected. This is a concrete material that contains high permeability and mechanical intensity. In this experiment, slag and fine sand are used in substitute of concrete to test its differences. From the result of the experiment, we noticed that porous concrete contains high permeability and low unit weight. Due to the different specimen size and experiment method of porous concrete block and porous concrete, the confined effect has a greater impact on porous concrete block. In the experiment where slag substitute concrete (replacement by weigh), we can see from the result that when the substitution rate reaches 30%, it does not affect the entire mechanical intensity. Moreover, during the manufacturing of porous concrete block may bring conducive effect of demolding smoothly and with the addition of fine sand will reduce the mechanical intensity of porous concrete. The most optimal mixture or proportions of porous concrete is in between the water to cement ratio of 0.25 to 0.35 with (cement) paste volume of 55%. Under this condition, the fluidity and adhesiveness of (cement) paste is most appropriate which may effectively enwrap the surface of aggregate. This may enable the aggregate to contain sufficient of bond and effectively perform the permeability of porous concrete. Porous concrete product contains high permeability and mechanical intensity which may be applied to construction that does not require high intensity, such as pedestrian trails, parking lots paved road and farmland drainage. It can also conserve water to provide for plant growth which can protect our ecological system, beautify the environment, and save energy.
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Wang, Wei-Hai, and 王威海. "Research porous concrete allocated proportion experiment." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/84276075655500071245.
Full textAbstract:
碩士逢甲大學
水利工程所
95
In recent years environmental protection consciousness gradually took, also the traditional concrete had its shortcoming, namely of the porosity and the water permeability was bad, did not conform to requirement the ecology material, therefore this research was take the traditional concrete material as the research foundation, developed the water-permeable concrete by this foundation to become the new ecology material, provided application of reference the environment landscape and the project. Therefore, this research through a series of experiments and the analysis, including bone material basic nature experiment, multi- holes concrete basic project nature experiment, allocated proportion of design the multi- holes concrete and hangs flows the experiment and so on five items, and obtains the preliminary achievement. 1. Best water-cement ratio pushes estimates by way of hangs flows the experiment to discover best water-cement ratio, the bone material particle size scope of in the 37.5~50mm, by way of hangs flows the experiment to be best water-cement ratio is 0.32~0.36, indicated the chassis comparatively not infiltrates the thick liquid situation. 2. Scope of water percolation of coefficient the water percolation coefficient this experiment is 4~22 cm/sec, expressed the multi- holes concrete has the high water percolation ability. 3. the porosity when water-cement ratio the value increases, the porosity value reduction. 4. The cleavage strength knew by the experiment, tensile strength of range multi- holes concrete, therefore cannot treat as the main structure to have auxiliary by other structure combinations, can display characteristic of the multi- holes concrete. 5. Of the compressive strength thick liquid bone compared to is enhances the multi- holes concrete intensity the primary factor, in order to achieve request the project, still must consider plants idea of the fresh project and the ecological engineering, therefore must conform to the porosity and correlation of requirement the water percolation coefficient.
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Yun-CiYang and 楊允祺. "Engineering Properties of Porous Asphalt Concrete." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/32866029899390804274.
Full textAbstract:
碩士國立成功大學
土木工程學系碩博士班
98
Porous asphalt concrete is an alternative to traditional hot mix asphalt and is produced by eliminating the fine aggregate from the asphaltmix. Rain that falls on the friction course drains through the porous layer to the original impervious road surface at which point the water drains along the boundary between the pavement types until the runoff emerges at the edge of the pavement. Porous asphalt concrete overlays are used to improve drivability in wet weather conditions and to reduce noise from highway traffic. The void space in porous asphalt concrete overlay layer generally is 15-25%. Taiwan special climatic environment, enables porous asphalt concrete to have the opportunity to be at the moist condition for a long time. This research uses the same porous asphalt concrete mix design result, coordinates three kind of different asphalt to make the mixture: AR-8000 asphalt, high viscosity asphalt and modified III asphalt. And soaks mixtures in water on 60℃ several days: 0, 1, 3 and 7 days. Mixtures after the immersion condition function carries on the project experiment: The indirect tensile test, the static creep test, the dynamic creep test, the track test, and the resilient modulus test, to appraise the different immersion condition function to influence of the porous asphalt concrete mixture. This ratio of parameters affected by moisture conditioning to the control state is referred to moisture damage ratio. Demonstrated according to the result that without immersion condition, three kind of mixture's indirect tensile are close. After immersing 1 day-long condition function, the indirect tensile of AR-8000 asphalt mixture drop is 0.8 time, the indirect tensile of modified III asphalt mixture drop is 0.86 time, the indirect tensile of high viscosity asphalt mixture drop is 0.89 time. And immerses 3, 7 day-long condition functions to present the same tendency, the high viscosity asphalt mixture has the higher moisture damage ratio, and the AR-8000 asphalt mixture has the lower moisture damage ratio. Other test result all presents the same tendency. Synthesizes each result, the high viscosity asphalt mixture and modified III asphalt mixture are highly resistant to moisture damage, and AR-8000 asphalt is lowly. In addition antistrip additive was effective to decrease the moisture damage in AR-8000 asphalt mixture.
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Shen, Mei-i., and 沈美毅. "Reuse of Waste Concrete in Open Graded and Porous Asphalt Concrete." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/19832645550602031757.
Full textAbstract:
碩士淡江大學
土木工程學系
91
This research was focused on the feasibility of reusing demolished construction waste concrete (containing bricks and tiles) and simulated waste concrete as aggregate in open-graded asphalt concrete and porous asphalt. Different compositions of the waste concrete such as the OGFC-A (natural aggregate group), the OGFC-B (demolished construction waste group) and the OGFC-C (simulated waste group) were assigned for open-graded asphalt concrete, while the PAC-A (natural aggregate group), the PAC-B (demolished construction waste group) and the PAC-C (simulated waste group) for porous asphalt. Tests conducted included the Marshall stability, resilient modulus, indirect tensile strength, permeability, skid resistance, Cantabria, oven aging, stripping and wheel tracking tests. Major findings of this research study are summarized as follows: 1.There was no difference in resilient modulus for all groups at 25℃. Resilient modules of the waste group were higher than those of the natural group at 40℃. Indirect tensile strengths of the demolished construction waste were the highest among all groups, and indirect tensile strengths of porous asphalt were higher than those of open graded at both 25℃ and 40℃. 2.Permeability coefficients of the waste group were similar to those of the natural aggregate group and all higher than 0.01 cm/sec. Permeability coefficients of open graded were slightly higher than that of porous asphalt. Skid resistance values of the waste group were similar to those of the natural aggregate group, while open graded were higher than that of porous asphalt. Cantabria wear values of the waste group were lower than that of the natural aggregate group. 3.Marshall stability after oven aging increased along with aging time while Marshall flow decreased for all groups. Retained Marshall stability percentages of all groups were higher than the specified value of 75%, while the natural aggregate group were higher than those of the waste group. 4.Rutting deformations of the waste group was smaller than that of the natural aggregate group. No significant difference was observed in dynamic stability between the waste group and the natural aggregate group. Dynamic stability values of all groups were higher than the specified 3,000 times/mm. Research results also showed that there was no significant difference between the simulated waste group and the demolished construction waste group, and both waste groups were superior to the natural aggregate group. Further field trials were recommended to verify the performance of the reuse.
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Chien-ChungHuang and 黃建中. "Analysis of Characteristics of Porous Asphalt Concrete." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/47996088316690376927.
Full textAbstract:
博士國立成功大學
土木工程學系碩博士班
99
The study discussed the applications of porous asphalt concrete (PAC), including characteristics of polymer modified asphalt (PMA), moisture damage, clogging of pores, and interface bonding of pavement structure. The results may serve as reference for highway agencies in the use of PAC composite flexible pavement and the evaluation of PAC pavement. The results have shown that sulfur solubilizer was able to improve the compatibility between asphalt in sub-base and SBS, to effectively reduce phase separation of PMA when stored in high temperature, and to decrease the SBS needed for PMA network structure. These were the effects of sulfur during the reinforcing interaction between SBS grains. The Mooney viscosity model was used to revise the effective volume of SBS in asphalt, which was then put into the Nielsen model in order to predict the performance of sulfur-added PMA pavement. In terms of moisture damage of PAC, high-viscosity PAC had higher dissipated creep strain energy limit, which meant better ability to resist cracking. Moisture damage would lower the dissipated creep strain energy limit of the mixture. In terms of cracking-resistance, high-viscosity PAC was more cracking-resistant than Type III PMA, followed by AR-80 mixture. The longer the cold mix PAC was soaked in water, the lower the strength of the sample. With different additives, cold mix asphalts have shown significant differences in strength and moisture damage. Sample C and D showed better engineering properties. Permeability test of PAC showed that Ko/Kc and Ko/Kr could be used to determine the level of clogging and the efficacy of permeability. When Ko/Kc and Ko/Kr were more similar and the closer they were to 1.0, the more clogging-resistant the PAC was. After being tamped with wheel loading, porosity of AR-80, Type III PMA, and high-viscosity PAC decreased 1.5%, 1.0%, and 0.6% respectively; horizontal permeability coefficient decreased 31.6%, 33.6%, and 8.9% respectively; high-viscosity asphalt was clearly more permeable. The research of binding in PAC pavement has found that interfaces without tack coat had higher cohesion in DAC-DAC, PAC-DAC, PAC-SMA, and PAC-Guss. When the surface was clean and coated with asphalt, tack coat was dispensable. Asphalt concrete is very susceptible to temperature and has better engineering properties in lower temperature. The test results also showed that the interface shear stress of PAC-SMA was least susceptible to temperature. The interlocking mechanism of aggregate has shown that less different asphalt concrete interface gradation would help reduce temperature susceptibility.
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Tai-YingWu and 吳泰穎. "Effect of OMRS on Porous Asphalt Concrete." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/80196175121122602356.
Full textAbstract:
碩士國立成功大學
土木工程學系碩博士班
100
Organo-Modified Reservoir Sludge (OMRS) is a good example for re-use of waste resources. The modification technology of reservoir sludge which as an environmental problem turns the reservoir sludge into waterproof material and develops waterproof products which increase reservoir sludge added-value. Porous Asphalt Concrete(PAC) excludes water quickly with high air void content , but it’s easy to cause stripping and raveling in pavement by moisture damage. To improve the resistance of pavement for moisture damage, OMRS , lime and cement were used in this research as fillers in PAC mixtures. The results showed that there was no effect in the permeability coefficient for adding different fillers in the mixtures. In mechanical properties , the strength of specimens with OMRS was weaker than others. Then, three kinds of fillers had similar results on the first day in residual strength test. And it could be found that the longer the specimens soaked in water, the smaller TSR value had .The PAC mixtures with OMRS had better performance in anti-moisture damage.
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Zhuang, Guu-yang, and 莊谷暘. "Experimental study of planting on porous concrete." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/03822524406522168563.
Full textAbstract:
碩士逢甲大學
水利工程所
94
Due to the environmental protection consciousness gradually being popularize in recent years, therefore, in the hydraulic engineering, it’s important to think over the green landscaping and ecological conservation when the works project was devised & constructed. Consequently, the government is exerting their great efforts to promote the ecological engineering method to be the major method when they rebuild the rivers. In order to conform this tide , application of the porous concrete and the conception of planting in the porous concrete has be produce .As the porous concrete equipped with the superior characters such as porousness, permeability & coarseness. It’s really a new idea and a new technique that makes the people dream came true which the grass can be even grown in the concrete. What is more ,it not only meets the safety engineers but also keep the natural landscape and make the variety in biotic habitats .。 There are totally six factors are adopted in the vegetation testing , such as sunshine, coarse aggregate partical size, porosity、hillside condition、soil proportion and grass seeds .Then to observe what will be the impact to the vegetation in case of any factor is being changed during the test. According to the experiment, we can find these. 1. It make no difference whether the plane Paspalum notatum grew in the porous concrete under fine partical size (15 mm-19.5mm) or coarse partical size( 19.5 mm-25mm). However, with the 45° slope, the growth under the fine partical size growing more flourishing than it under the coarse partical size, at the same time the root capability of penetration are became more and more obviously as well. 2. It makes no difference in the growth condition whether the Cynodon dactylon was grown in the fine partical size / coarse partical size or in plane/45° slope. 3. It makes no difference in the growth condition whether the Zoysia tenuifolia was grown in the fine partical size / coarse partical size or in plane//45° slope.
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Shieh, Fu-Chuam, and 謝富全. "Application of Porous Concrete in Drainage Engineering." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/04516897605085845459.
Full textAbstract:
碩士國立中興大學
土木工程學系所
105
In recent years, due to various new materials and new engineering operate mode, in the meantime the environmental awareness.Traditional concrete-based drainage work is no longer the best choice. Green landscaping, ecological conservation , environmental protection , energy conservation , and water conservation , have become the focus of drainage engineering design and construction. Therefore, the water conservancy engineering and water conservation engineering , i.e. Ecological engineering methods is the government in the public construction to vigorously promote topic in recent years. In addition, in line with the base water retention indicators, construction materials permeability has become an essential element. Among the many materials, porous concrete provide with the following three major functions，first is water into and out easily , second is easy to plant greening and the other is easy to obtain. In addition, the construction method largely identical but with minor differences with the general concrete, therefore become a favorable alternative materials. In this study, the influence of the permeability coefficient of the porous concrete, the relationship between the shape and the flow rate of the drainage facility and the influence of the porous concrete on the soil infiltration were analyzed. According to the engineering case and experience, the paper, the literature and the comparative analysis were obtained. The best porous concrete is used in different soil and ditch type arrangement, to balance the budget, material and work. In the comparison of the general ready-mix concrete, multi-porous ready-mixed concrete and light ready-mixed concrete budget, the average pre-mixed concrete and multi-pore ready-mixed concrete price difference is about NT $ 460 to 550 per M3, or only 25% Water flow coefficient of 7cm / s ~ 11cm / s, Q flow (m3 / day) from 0 m3 / day, increased to 2.68 m3 / day, is indeed conducive to engineering water conservation and its necessary to promote, but the ceramic light ready-mixed concrete per M3 is about NT $ 7,000. Due to the high price is still unacceptable on the market, follow-up need to be promoted by public construction and to be mass production . Until the former advance,the industrial enterprise can accept its prices.
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Pereira, Matheus. "Estudo da absorção sonora de materiais granulares e sistemas híbridos com estruturas ressonantes." Doctoral thesis, 2020. http://hdl.handle.net/10316/96361.
Full textAbstract:
Tese no âmbito do Doutoramento em Engenharia Civil, Construções orientada pelos Professores Doutores Luís Manuel Cortesão Godinho, Paulo Jorge Rodrigues Amado Mendes e Jaime Ramis Soriano e apresentada ao Departamento de Engenharia Civil da Faculdade de Ciências e Tecnologia da Universidade de Coimbra.Materiais porosos absorventes sonoros são de grande interesse para soluções de controle de ruído passivo. A presente tese de doutoramento apresenta estratégias eficazes para o desenvolvimento de soluções otimizadas para aplicação em meios exteriores, sem necessidade de reforço estrutural. O estudo de materiais porosos granulares com agregados de argila expandida procurou entender a influência da relação água cimento, da espessura e do tamanho dos agregados no coeficiente de absorção sonora exibido por estes materiais quando diretamente expostos à incidência de ondas sonoras no exterior. Estes materiais foram caracterizados experimentalmente com técnicas não destrutivas, e os seus parâmetros macroscópicos obtidos com utilização de um método inverso, possibilitando a previsão do coeficiente de absorção sonora com o modelo semifenomenológico de Horoshenkov-Swift. Para o estudo do comportamento absorvente considerando incidência difusa, um modelo BEM 3D foi proposto e validado de maneira satisfatória, permitindo a aplicação de geometrias irregulares em painéis de absorção sonora de tamanho finito. Este modelo possibilita a análise de configurações em que as irregularidades geométricas superficiais proporcionam um acréscimo no coeficiente de absorção numa determinada gama de frequências. Este assunto é de grande interesse, considerando que materiais do tipo betão poroso possuem curvas do coeficiente de absorção sonora compostas por picos e vales. O conceito denominado Metabetão poroso é definido e apresentado, correspondendo ao acoplamento entre dois dispositivos de absorção sonora, nomeadamente material poroso (betão poroso com agregados leves) e ressoadores acústicos embutidos. Dois modelos FEM, um 2D e outro 3D, foram propostos e validados para o estudo da otimização da geometria desta solução híbrida, com o objetivo de atingir um acréscimo de eficácia no coeficiente de absorção sonora. Por último, apresenta-se uma estratégia de previsão do comportamento absorvente considerando incidência difusa, para uma metasuperfície de tamanho finito com 12 m^2 de área. Para além das considerações finais, enumeram-se algumas ideias para trabalhos futuros. Esta tese foi desenvolvida no âmbito do Projeto POCI-01-0247-FEDER-033990 (iNBRail), financiado por fundos FEDER através do COMPETE 2020, Portugal 2020. Esta tese foi igualmente apoiada por fundos FEDER através do Programa Operacional Fatores de Competitividade - COMPETE e por fundos nacionais através da FCT – Fundação para a Ciência e a Tecnologia, no âmbito do projeto POCI-01-0145-FEDER-007633 (ISISE) e através do Programa Operacional Regional CENTRO2020 no âmbito do projeto CENTRO-01-0145-FEDER-000006. O apoio da COST (European Cooperation in Science and Technology) através da Ação COST CA15125 – DENORMS: “Designs for Noise Reducing Materials and Structures” é aqui igualmente reconhecido pelas oportunidades concedidas.
Porous sound-absorbing materials are of great interest in passive noise control solutions. This doctoral thesis presents effective strategies for developing optimized solutions for use inexternal environments without the need for structural reinforcement. The study of granular porous materials with expanded clay aggregates was developed in order to understand the influence of water-cement ratio,thethickness and size of the aggregates on the sound absorption coeficiente exhibited by these materials when directly exposed to the incidence of sound waves outside. These materials were characterized experimentally with non-destructive techniques,and their macroscopic parameters, obtained using the inverse method, allowed the prediction of the sound absorption coeficiente with the Horoshenkov-Swift semi-phenomenological model. For the study of absorbente behavior for diffuse incidence, a BEM 3Dmodel was proposed and satisfactorily validated, allowing the application of irregular geometries infinite-sized absorbing panels. This model makes it possible to find configurations where geometrical irregularities provide na increase in the coefficient of sound absorption in a certain frequecy range. This is na importante step considering that porous materials have absorption coeficiente curvers composed of peaks and valleys. The concept called Metaporous concrete is defined and presented, it corresponds to the coupling between two sound absorption devices, namely porous material (porous concrete with light aggregates) and embedded acoustic resonators. Two FEM models, one 2D and the other 3D, were proposed and validated to study the optimization of the geometry of this hybrid solution to increase the sound absorption coefficient. Finally, na absorbing behavior predictions trategy is presented considering diffuse incidence for a finite size meta-surface in 12m2. In ad dition to the final conclusions and some ideas for future works are listed. This thesis was developed within the scope of the POCI-01-0247-FEDER-033990 (iNBRail) Project, funded by FEDER funds through COMPETE2020, Portugal 2020. This thesis was also supported by FEDER funds through the Competitivity Factors Operational Programme-COMPETE and by national funds through FCT– Foundation for Science and Technology within the scope of the project POCI-01-0145-FEDER-007633(ISISE) and through the Regional Operational Programme CENTRO2020 within the scope of the project CENTRO-01-0145-FEDER-000006. The support of COST (European Cooperation in Science and Technology) through the COST Action CA15125 – DENORMS: “Designs for Noise Reducing Materials and Structures” is here also acknowledged.
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Chen, Wei-Cheng, and 陳韋誠. "The Application of Porous Concrete in Construction Engineering." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/62607279369786147527.
Full textAbstract:
碩士中興大學
土木工程學系所
99
In recent years, the government began to promote green building, which is ecological, energy conserving, waste reducing and healthy buildings. And ecology is the most important among these qualities. In Taiwan, abundant rainfall makes rivers short and rushing, making the application of water resources a serious challenge. Therefore, we develop a new material, porous concrete, which is beneficial to water retaining, drainage and ecology. The study variables are aggregate size and type, water-cement ratio and cement paste volume. The coarse aggregate grain size is 5 mm ~ 10 mm, 10 mm ~ 20 mm and recycled aggregate grain size is 10 mm ~ 20 mm. Water-cement ratio are 0.25,0.30,0.35 and 0.40. Total pore volume of cement paste volume are 30,35,40 and 50% of the volume. We also added pozzolans materials and superplasticizer to change the amount of cement used and cement paste workability. The results showed that, the porous concrete unit weight locate between 1440 kg / m3 ~ 1760 kg / m3, which is approximately 62% to 76% of normal concrete (2300 kg / m3). The porosity was about 28% to 42%. Permeability coefficient was about 7.73cm / sec ~ 13.20 cm / sec. Compressive strength of was 32.8 kgf / cm2 ~ 122.5 kgf / cm2. And cement paste flow value control was 105% ± 5%. Porous concrete performed well when applied in construction projects. The compressive strength of up to 194.3 kgf / cm2 and the porosity is 20% or more, making it a suitable permeable material. The porous concrete is adequate to structure usage( concrete strength175 kgf / cm2) and the quality of its engineering is suitable for porous concrete projects such as bank protection, slope protection, channel. etc.
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Shung-YaoShin and 施盛耀. "Engineering Properties of Cold-Mix Porous Asphalt Concrete." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/05665858719414001056.
Full textAbstract:
碩士國立成功大學
土木工程學系碩博士班
98
Due to Taiwan's geographical location and subtropical climate with high rainfall, paving porous asphalt concrete (Porous Asphalt Concrete, PAC) is used to reduce skid and puddle splashes. Regular maintenance is not required with the increase usage of porous asphalt concrete. Cold mix asphalt concrete (Cold-Mix Asphalt, CMA), also known as room temperature asphalt concrete is a mix which used by the road maintenance unit as temporary pothole repairs. It needs to be stored at room temperature after leaving the factory. We will research the 3 different porous asphalt concrete cold mix ratio design method where the outcome will determine the standard configuration of the cold mix specimens that is the most suitable for current road conditions. To establish the cold-mix asphalt concrete porous specifications, we will need to reference the porous asphalt concrete hot mix pilot projects. We need to also study the hot and cold mix of density gradation differences. By experimenting the cold mix asphalt concrete porous in damp condition, the result shows that the engineering properties of intensity varies from different experimental results. The cold-mix asphalt under various damp conditions produces variable intensity losses. On another note, the Clegg Soil Impact Tester is also conducted to get the current to the pavement Clegg Impact Value (Clegg Impact Value, CIV). The study is used to assess the way different asphalt types and different structure types reacts and produces different Clegg impact value. Apart from that, the result also shows that higher strength of asphalt known type and structure type shows higher Clegg impact value.
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Huang, Yu-Ming, and 黃育明. "Performance of In Situ Porous Asphalt Concrete Pavement." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/78409797129811309952.
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Lo, Chang-Chuan, and 羅常銓. "Porous concrete allocated proportion experiment and applied research." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/60833810272601830068.
Full textAbstract:
碩士逢甲大學
水利工程所
95
In order to conform to requirement the ecology material, therefore this research is take the traditional concrete material as the research foundation, develops the multi- holes concrete by this foundation to become the new ecology material, provides application of reference the environment landscape and the project Therefore, this research through a series of experiments and the analysis, including bone material basic nature experiment, allocated proportion of design porous concrete basic project nature experiment, the porous concrete and hangs flows the experiment and so on five items, and obtains the preliminary achievement. The best water-cement ratio pushes estimates by way of hangs flows the experiment to obtain best,water-cement ratio may obtain a marginal value, if ,water-cement ratio surpasses 0.35, then will infiltrate the thick liquid quantity to be able to create the chassis to have infiltrates the thick liquid situation occurrence; If ,water-cement ratio is lower than 0.35,then the chassis not infiltrates the thick liquid situation. Experiment scope value water percolation of coefficient the water percolation coefficient this experiment is the 2.356~11.374cm/sec coefficient. this experiment Porosity scope 0.02~0.37, approximately some 53% allocated proportion design conforms to the Japanese concrete association (2,005) to stipulate Porosity must reach 30%. The cleavage strength by the split test knew the scope is 1.72~17.96 , knows tensile strength of range the water percolation concrete by the experiment, therefore cannot treat as the main structure to have auxiliary by other structure combinations, can display characteristic of the water percolation concrete. In compressive strength this research, the compressive strength maximum value is, reorganizes the experiment based on the tentative data the allocated proportion design, according to needs the project nature according to the table inquiry, and the establishment construction standard and the job practice provide using of the engineering design reference.
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Yi-HsinChang and 張義欣. "Case study of porous concrete with Recycled aggreste." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/sezd6e.
Full textAbstract:
碩士國立成功大學
土木工程學系碩士在職專班
104
This study was the first test of the physical properties of recycled materials. Followed by recycled materials used in Porous concrete and the relevant checks to evaluate its compressive strength, permeability coefficient and water permeability and other functions. Whether the current allowable value meet specifications. And aggregate materials and new incinerator bottom slag mixes by mixing the differentially Porous concrete benefits and cost analysis to discuss the applicability of recycled materials. Then further investigate the effectiveness of its projects.
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Kai-HuiHuang and 黃凱輝. "Production, Quality and Performance of Porous Asphalt Concrete." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/u9h2mw.
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Lin, Yi-Yu, and 林奕妤. "Interlocking Effecton Performance of Porous Asphalt Concrete Mixture." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/73103602638963861417.
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LI, YIN-CHENG, and 李胤誠. "Research pore characteristics of porous asphalt concrete grading." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/23464190643726338173.
Full textAbstract:
碩士東南科技大學
營建科技與防災研究所
102
In recent years, Taipei, in the promotion of road level project, expected to go through a variety of ways to reduce traffic on the safety and avoid public life, property damage, this study aims to investigate the relevant graded porous asphalt concrete pore characteristics and analysis of different properties discuss the direction to improve the porosity of the pavement to give appropriate recommendations for future reference. Level used in this study with reference to Europe FHWA, NCAT, Japan drainage pavement design specifications and North American states are graded, selected, plus asphalt high strength, making porous asphalt concrete specimen, followed by conducting permeability test, pore test and other test rate, the analysis of various physical parameters gradation correlation value table and graph features, to evaluate the effectiveness of various countries are not at the same level with permeable porous asphalt concrete. Therefore, the test results should be considered in order to avoid flooding porosity when it rains, because the amount of rainfall, but not readily penetrate to the bottom of the water, resulting in lower permeability function, and even cause water to use passers safety is at risk.
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Sheng-FuLang and 郎勝富. "Distress and Maintenance of Porous Asphalt Concrete(PAC)." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/05179226058438382221.
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Ho-TsoChiang and 江禾左. "Effect of Blast Furnace Slag on Porous Asphalt Concrete." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/32115477221380681893.
Full textAbstract:
碩士國立成功大學
土木工程學系碩博士班
100
Blast furnace slag, the by-product of the ironmaking process, have been used as an alternative material widely; Mineral powder and cement ,used for asphalt concrete filler,both are from the exploitation of the natural environment.The uniformity and composition of blast furnace slag are similar to cement, the cost is also more economical. In this study,mineral powder ,blast furnace slag and cement were used in porous asphalt concrete for assessment. The results showed that it had a better performance in the Marshall flow value, indirect tensile strength, resilient modulus and resistance to abrasion of Cantabro when the blast furnace slag was used as the filler,It significantly improved the stiffness of the Marshall specimens,cement and mineral powder had better performance in anti-stripping, and the blast furnace slag also performed well. The results of the research showed that the slag can be used as a filler in the porous asphalt concrete.
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Tseng, Huai-Ku, and 曾懷谷. "Performance Evaluation of Various Porous Asphalt Concrete Design Method." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/72364118884489597479.
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De-HshienLiu and 劉德賢. "Evaluation of Porous Asphalt Concrete Applied to Pavement Rehabilitation." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/42774046932017631917.
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碩士國立成功大學
土木工程學系碩士在職專班
102
China in the late 1990s to introduce porous asphalt concrete (Porous Asphalt Concrete, PAC) pavement technology, After practical experience mature gradually being widely and quickly laid on the national highway road. Nantou section of National Highway No. 6 of 2009 opened, is the first line of the highway using PAC; 2012 Taichung life rings of road traffic on the 4th (station 74), and the National Highway No. 1, paragraph five bayberry also widened across the board with PAC. By this study were functional pavement performance, durability and safety evaluation test; containing functional water permeability and the amount of noise, comprising rutting durability, flatness, and Clegg, impact resistance, safety against sliding of the measurement values. Explore the nominal maximum particle size, paving the way for the influence of the thickness and eliminating assess the actual use of PAC paved national highway in the southern part of the performance, PAC pavement life and improving service quality. Research shows that National Highway No. 8, and 10 large-scale conservation using PAC pavement, short-situ test data show that the test trend analysis functionality, durability and safety performance is good. Excluding the proceeds generally used to mean eliminating the groove 9.1mm, eliminating fine lines mean eliminating the groove of 4.2mm. Trench depth of eliminating the results of three different thickness meas-urements are substantially the same, showing the general appearance of fine lines and eliminating eliminating eliminating different ways, affecting eliminating trench depth
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Wang, Jun-pin, and 汪峻平. "Evaluation of Gap Aggregate Gradation on Porous Asphalt Concrete." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/86547014983696298652.
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碩士國立成功大學
土木工程學系碩博士班
96
The objectives of this study is to investigate the effects of aggregate gradation on the engineering properties and pavement performance of asphalt concrete by changing aggregate gradation and deleting the aggregate sieves number. Setting the aggregate gradation by deleting aggregate sieves number to form a gap gradation. The attempt gradation deletes 3/4”, 1/2”, 3/8”, #4, #8, #16, and #200 sieves. The occupying proportional is deleted by size distribution to other sizes. The PMA3 was used as binder in this study. These mixtures were designed by the Japanese mix design., we carry out performance test of porous asphalt concrete. Based on test results, the gradation and proportion of coarse to fine aggregate are major factor to effect the engineering properties. The asphalt concrete with coarse aggregate and higher air voids will have less stability. Simultaneously, it produces more rutting. Of all these gradation, the gradation deleting 1/2” has the best performance. Suitable the gradation and proportion of coarse to fine aggregate could have positive effects in draining ability,anit-abrasion and rutting ability. Key words：Gap aggregate gradation , Porous asphalt concrete
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Lin, Hsiu-Chen, and 林綉禎. "Application of Nano Photocatalyst Porous Concrete on Air Purification." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/up2452.
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碩士國立臺灣科技大學
營建工程系
95
The environmental purify has become the most important issue among all the countries. The nano-photocatalyst has the ability to improve the environmental problem such as air pollution. At present, due to no side effect occur the nano-photocatalyst has widely applied to air purification. The study focus on application of Photocatalyst combines with the porous concrete as outdoor air purification material to solve the air pollution problem of Taiwan. To evaluate the photocatalysts reaction under conditions of low humidity and room temperature, the three variables, air voids of porous concrete, intensity of UV light, and factor of SiO2, were considered. Moreover, the reversion efficiency was investigated by perform the water clean method. The test results show that amount of adsorption of NO2 is affected by box wall and porous concrete. Thus, the degradation speed of initial stage is faster then later stage. As expected, the high intensity UV light result in a high photocatalysts reaction. The test result shows that before water clean the porous concrete has faster degradation speed than after water clean one. However, the reversion efficiency for each test groups has upward to 80%. Furthermore, the porous concrete that surface treating by SiO2 and then coating nano-photocatalyst has high degradation performance. Therefore, the middle layer as SiO2 can helps the long term durability. The nano-photocatalyst of situations of film formation and adhesion is affected by the air voids of porous concrete, and result in different photocatalysts reaction. Based on test results indicating the air voids of porous concrete at 15% and 20% have excellent ability of air purification. In according the statistical analysis show that 20% air voids was recommended to be the appropriate air voids contend.
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Po-HsienLee and 李柏賢. "Analyses of Factors Affecting Performance of Porous Asphalt Concrete." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/52cc4s.
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碩士國立成功大學
土木工程學系
103
Porous asphalt concrete (PAC) has water permeability, surface roughness, to provide sufficient frictional resistance, improve security and other features, and gradually the use of the highway authorities. This study investigated the PAC paving on National Highway No. 3, 8 and 10 of performance, performance contain functionality, durability and safety of the three categories, and will be open graded friction Course (OGFC) included in the comparative effects of different nominal maximum aggregate size (NMAS), paving thickness, asphalt type, as well as generally and fine eliminating respectively compared eliminating manner, and to assess the impact on traffic load Equivalent Single Axle Load (ESAL) value of pavement performance. Studies have shown that paving thickness and nominal maximum aggregate size (NMAS) are affecting road noise reduction effect, paving thickness increases from 3cm to 5cm, the better the noise reduction effect, and water permeability after more traffic compaction can be maintained, but also more resistant to rutting amount of traffic load form. Conservation time after the completion of the road paved directly affect the PAC functionality and durability, under the same paving thickness, adequate conservation roads have the same permeability and rutted of the remaining sections, asphalt species also have significantly effect on performance, the use of high viscosity asphalt pavement PAC have better functionality and durability; PAC has little effect on the performance of the way the eliminating from short-term performance data. Cost considerations, construction and long-term performance, we recommend maintenance road paved 4cm thick, NMAS 19 mm of the PAC.
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Hsueh-YunTsai and 蔡雪雲. "Performance Evaluation of Porous Asphalt Concrete with Various Thicknesses." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/38kbka.
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Chien-HauChen and 陳健豪. "Functionality、Durability and Safety of Porous Asphalt Concrete Pavement." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/35ta9y.
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He, Jia-Hua, and 何佳樺. "Physical properties of porous asphalt concrete containing crashed glass." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/50678919378700376097.
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碩士國立屏東科技大學
土木工程系所
102
With the recent increase of global environmental consciousness and energy shortages, the crashed glass used in road pavements will become the major trend. The goals of resources recovery and sustainable development can be achieved. Due to high temperature and intensive rain in the Taiwan, the porous asphalt pavements have been adopted gradually in recent years. Besides the rapid drainage of surface water through its matrix, a positive benefit reducing the urban heat island effect is also expected. Properties of crashed glass, crashed TFT-LCD glass, and natural aggregate are analyzed in this research. Seven proportions of porous asphalt concrete containing natural aggregate and both the crashed glass are made. In the AC specimens, different weights of natural fine aggregate are replaced the crashed glass, #16~#200 natural fine aggregate are replaced by crashed #16~#200 glass and #100 TFT-LCD glass respectively. It also contains pulverized furnace slag powder as filler in the AC specimens. Marshall test is held to determine the optimum asphalt contents of the proportion proposed above. The void ratio, permeability, Marshall stabilities and flow values of the AC specimens made in this study are then measured. The specific gravity is 2.49 of crashed glass which is lower than 2.55 of natural fine aggregate. Replacing natural aggregate by crashed glass will lead increase of the asphalt consumption and cost of the asphalt concrete. Marshall flow values of the AC specimens also increasse when glass aggregate substitution increases.
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Lai, Jiun-Yang, and 賴俊仰. "Evaluation of Porous Asphalt Concrete Used in Highway Performance." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/41097277336614746543.
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碩士國立成功大學
土木工程學系碩博士班
97
Taiwan is a monsoon-climate country with annual rainfall of 100 days. This phenomenon makes the road which is made by traditional dense asphalt easily covered with water film or mists. In order to prevent this situation, a drainage pavement is developed. There were nine pavement test sections with five major tests in this research. The five tests consist of field permeameter, rutting, roughness, skid resistance, and noise tests. Of the five tests, the wheel tracking test was conducted in the laboratory. These experiments aimed to collect data on the following issues: the road conditions before and after open to the traffic; the different paving on the bridge deck or road embankment; comparison between the in-lab wheel tracking and field rutting test; the noise level in different road types. The research concluded that using various sections from various materials with different asphalts, gradations, asphalt contents and porosity values. In comparison between the bridge deck and the road embankment sections, the results showed no significant difference. For asphalt paving materials, the field permeameter test and rutting test results revealed that using of high-viscosity asphalt had better performance on permeability. High-viscosity asphalt had better rutting resistance than using AR-80. After one-year traffic, the International Roughness Index (IRI) of the road surface was still within the required standard, and the skid resistance ability was also in good condition of which above 50 BPN. The results of environmental noise in dense asphalt pavement and rigid pavement were more than porous asphalt pavement by as much as up to 8 dB, showing porous asphalt concrete pavement was effective to reduce noise.
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Lin, Chun-Young, and 林峻央. "Effects of adding lime methods on Porous Asphalt Concrete." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/74022174643098957787.
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碩士國立成功大學
土木工程學系碩博士班
94
Porous asphalt concrete is described by air void ranging from 15 to 25 percent, it allows surface water to drain through its strcture rapidly. Porous asphalt pavements can reduce vehicle pray,and improve skid resistance. Adding lime can have multiple benefits in asphalt concrete. Purposes of this research were to evaluate how to add lime and how much lime could improve the Performance of Porous Asphalt Concrete. Objective of this research is to determine the use of AC20 asphalt affecting the performance of porous asphalt mixes . Marshall Specimens were prepared for mix design , stability , Indirect Tension test, moisture resistance and Cantabro Abrasion test . Results of the test showed that adding 1% lime was more resistant to stripping;Treatments of aggregate were effective – either as a slurry to dry aggregate or as dry lime to wet aggregate. Marination of treated aggregates improved performance. Treatment of dry lime to dry-cold aggregate was ineffective.The results of stability showed that dry lime to aggregate had better performace than slurry or dry lime to wet aggregate.
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liao, chia-yu, and 廖家佑. "A study on the mix proportion test of porous concrete." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/06452968391170418906.
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碩士逢甲大學
土木工程所
99
Porous concrete is a mixture of coarse aggregate, Portland cement, water and little to no sand. A typical pervious concrete pavement has a 15-25% void structure and allows 3-8 gallons of water per minute to pass through each square foot. Using the generally aggregate carefully controlled amounts of water and cementitious materials are used to create a paste that forms a thick coating around aggregate particles without flowing off during mixing and placing. Using just enough paste to coat the particles maintains a system of interconnected voids. This research is explored with systemic and sequential of mixed proportion designs and tests, in order to regain high strength permeable concrete material mixed proportion. It is found from this study that the manufacture procedure and test standard in porous concrete are buildup for the applications of pervious concrete in Taiwan. This performance of pervious concrete study result will be valuable for construction , and application practice . Keyword：
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Yung-ChiuanChen and 陳永全. "Analysis of Permeability and Dielectric Properties of Porous Asphalt Concrete." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/22749086994518544697.
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碩士國立成功大學
土木工程學系碩博士班
98
Porous asphalt concrete is designed with high porosity, with equivalent permeability. It can effectively reduce the possible rain water in the street, and to increase the surface friction, reducing the possibility of wheel slip. PAC can also reduce traffic-induced noise by absorbing noise. Pores will be clogged by sand and reduce porosity, resulting in permeability properties decreasing. Laboratory falling-head test measure K value has a good consistency with constant-head test. Falling-head test can measure K value on different water head, used to assess the drainage rate of PAC, and more understand the drainage characteristic of PAC. Research found, the rate of drainage is not proportional change with the thickness or head height, so K value can not maintain a constant value. Evaluating the effect of clog and compaction in laboratory drainage test, and then assess the in-situ permeability. Results shows KC/KO will decreased to 0.44. Clearing clog by suction will make KC/KO recovered to 0.58. High viscosity asphalt resistance to rutting best, then modify type III asphalt, AR-8000. Rutting has not obvious effect on vertical drainage, but except of HA with increase of rutting deformation, with decrease of permeability. By the relationship between K value and deformation can be constructed out of the pavement permeability model. Dielectric measurement as a kind of non-destructive testing, through the transmission and reflection of electromagnetic waves, which can effectively measure pavement thickness and density. To evaluate the change of pores between clog and deformation by dielectric measurement and experimental methods. Then constructing PAC density prediction model, and assess the relationship between K value and dielectric value. Key Words: permeability, falling-head test, dielectric value
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Wang, Yao-kuan, and 王耀寬. "Effect of Basic Oxygen Furnace Slag on Porous Asphalt Concrete." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/05295756210986826127.
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碩士國立成功大學
土木工程學系碩博士班
96
The development of technologies will promote people high quality living style. The requirement for the quality of traffic system, traffic service, and the vehicle safety are increasing. Because the weather in Taiwan was rainy, so Porous asphalt concrete（PAC）allows surface runoff to within it, thereby avoiding the wet-weather reduction of skid resistance, and splash/spray caused by the presence of a layer of water on the pavement surface. In PAC the role of the particle skeleton should be considered. However, due to lack of good-quality aggregate source, the last statement holds us to save natural resources by using industrial byproducts, as well as in other countries. Basic Oxygen Furnace（BOF）slag is a residual product of steel-making process, which is hard and durable with good angular shapes and high resistance to traffic abrasion. Because fresh BOF will hydrate rapidly and cause large-volume expansion, it should be during some aging time to alleviate the expansion potential. In this research, aging of BOF slag, for an estimated period of 0~3 months, were investigated. This paper mainly concerned the change of surface chemistry and physical properties of different period aging of BOF slag. Experiments were also performed to determine volume expansive of BOF slag and performance of BOF slag PAC. The asphalt binder film thickness of asphalt paving mixture were studied using scanning electron microscopy（SEM）. The results indicate that water absorption, L.A. abrasion and pH range decreased with aging time increased, whereas uncompacted void content and sand equivalent of fine BOF slag decreased, and other physical properties, specific gravity, soundness and the unit weight and voids in aggregate would not change with aging time increased. Base on the result of energy dispersive spectrometer（EDS）and x-ray diffraction analysis, the changes of element calcium and carbon were significant with increasing aging time. After 2 months, the variations of the ratio of volume expansive were not significant. Furthermore, results also indicate that, the value of Marshall stability, indirect strength, resilient modulus, and the ratio of Contabro abrasion, retained strength were better than control, after 2 months aging time. Base on the result of SEM observed, micro-particle concentration of mastics increases, due to add BOF slag in asphalt concrete, especially utilization of fine BOF slag as aggregate for PAC is quite significant. Thus the mixture of PAC which added fine BOF slag could provide higher strength and lower retained strength.
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Lu, Hui-Fang, and 呂慧芳. "Research porous asphalt concrete permeable characteristics of the aggregate grading." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/aajthj.
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碩士東南科技大學
營建與空間設計系營建科技與防災碩士班
106
In recent years, due to the global warming in Taiwan, extreme weather conditions have emerged and rainfall patterns have changed. As a result, the frequency of heavy rainfalls has increased. To address the frequent waterlogging and reduce the load on the drainage system, Taiwan has actively introduced porous materials into the pavement in recent years. We hope to improve traffic safety and water conservation by using porous materials. The gradations used in this study refer to FHWA and NCAT in Europe, the specifications of drainage pavement design in Japan and the grading rules of each state in North America. Using high-strength modified asphalt, the porous asphalt concrete specimens were prepared, and the water permeability test, porosity test And other tests, analysis of various gradation physical parameter correlation value chart and characteristics of the relationship between the map to assess the different levels of different countries with water-permeable asphalt concrete pervious to water. After gradation adjustment, the values of four parameters of porous asphalt concrete gradation, such as volume porosity, interconnected porosity, effective porosity ratio and permeability coefficient, have been significantly improved, which effectively improves the drainage effect and helps to understand the material properties and help the materials Design choice.