We are proudly a Ukrainian website. Our country was attacked by Russian Armed Forces on Feb. 24, 2022.
You can support the Ukrainian Army by following the link: https://savelife.in.ua/en/donate/.
Even the smallest donation is hugely appreciated.
Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями
Оберіть тип джерела:
Ознайомтеся зі списками актуальних статей, книг, дисертацій, тез та інших наукових джерел на тему "Shallow foundation system".
Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.
Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.
За допомогою хмари тегів ви можете побачити ще більше пов’язаних тем досліджень, а відповідні кнопки після кожного розділу сторінки дозволяють переглянути розширені списки книг, статей тощо на обрану тему.
Статті в журналах з теми "Shallow foundation system":
Leblouba, Moussa, Salah Al Toubat, Muhammad Ekhlasur Rahman, and Omer Mugheida. "Practical Soil-Shallow Foundation Model for Nonlinear Structural Analysis." Mathematical Problems in Engineering 2016 (2016): 1–10. http://dx.doi.org/10.1155/2016/4514152.
Soil-shallow foundation interaction models that are incorporated into most structural analysis programs generally lack accuracy and efficiency or neglect some aspects of foundation behavior. For instance, soil-shallow foundation systems have been observed to show both small and large loops under increasing amplitude load reversals. This paper presents a practical macroelement model for soil-shallow foundation system and its stability under simultaneous horizontal and vertical loads. The model comprises three spring elements: nonlinear horizontal, nonlinear rotational, and linear vertical springs. The proposed macroelement model was verified using experimental test results from large-scale model foundations subjected to small and large cyclic loading cases.
Naghibi, Farzaneh, and Gordon A. Fenton. "Target geotechnical reliability for redundant foundation systems." Canadian Geotechnical Journal 54, no. 7 (July 2017): 945–52. http://dx.doi.org/10.1139/cgj-2016-0478.
Geotechnical support systems (e.g., deep and shallow foundations) generally involve at least some redundancy. For example, if a building is supported by np separate foundations, then failure (e.g., excessive settlement) of a single foundation will generally not result in failure of the building if the building is able to shed the load from the failed foundation to adjacent foundations. This load-shedding ability lends the foundation system redundancy — system failure only occurs if multiple foundations fail. This paper investigates the relationship between the level of geotechnical redundancy, individual foundation reliability, and system reliability for deep foundations (piles). In the particular case where the pile resistance remains constant after achieving its ultimate capacity (at a certain displacement), the relationship between individual and system reliabilities is computed theoretically. The more general case, where the load carried by the pile reduces after exceeding its ultimate capacity, is investigated by Monte Carlo simulation. Charts relating system and individual reliability indices are presented, which can be used to aid in the design of individual piles as part of a pile support system.
Harden, Chad W., and Tara C. Hutchinson. "Beam-on-Nonlinear-Winkler-Foundation Modeling of Shallow, Rocking-Dominated Footings." Earthquake Spectra 25, no. 2 (May 2009): 277–300. http://dx.doi.org/10.1193/1.3110482.
The nonlinear behavior of shallow foundations under large amplitude earthquake-induced loading can result in dissipation of seismic energy through the mechanism of soil yielding beneath the foundation. In addition, foundation uplifting may shift the period of the soil-foundation-structure system away from the damaging energy content of most earthquakes. However, this yielding and uplifting may lead to excessive transient and permanent deformations (settlement, rocking, and sliding). Therefore, modeling procedures that account for foundation nonlinearity and uplift are needed before these benefits can be realized in performance based earthquake engineering (PBEE) practice. This paper adopts a beam-on-nonlinear-Winkler-foundation (BNWF) simulation methodology for modeling shallow foundation-structure systems, where seismically-induced rocking plays a predominant role in their response. Numerical results demonstrate that reasonable comparison between the nonlinear Winkler-based approach, and experimental response in terms of moment-rotation, settlement-rotation, and shear-sliding displacement can be obtained, given an appropriate selection of model and soil properties.
Sirat, Qurratu Aini, Dayangku Salma Awang Ismail, Azman Kassim, and Ahmad Safuan A. Rashid. "Application of distributed optical fibre for shallow foundation." MATEC Web of Conferences 250 (2018): 01019. http://dx.doi.org/10.1051/matecconf/201825001019.
Soil deformation is one of the major interests with regard to the stability analysis of the foundations. The deformations are signified for both vertical and lateral soil deformation; which the former plays vital role in designing a good foundation. As the stability of the foundation affect the stability of the entire structure, instrumentation and monitoring play an important roles in order to monitor the performances of the geotechnical structures. Until now the design of a foundation soil system is relied on the quantification of soil bearing capacity and foundation structural capacity and then followed by conventional monitoring system to observe the settlement so that within the allowable values. Therefore, this study focuses on the newly usage of distributed optical fibre sensing application to monitor strain distribution within a soil mass due to surcharge loading. It is expected to observe the strain distribution goes proportionally to vertical stress distribution concept; where higher strain measurement right below the loading position and decreases with depth. The advantage of distributed optical fibre sensing rather than conventional strain gauge is the sensor able to collect so-called average strain along the optical fibre compare to discrete measurement of strain gauge. This paper describes the experimental work conducted with the use of a distributed sensing technology named Brillouin Optical Time-Domain Analysis (BOTDA). A small scale of 1G model of a shallow foundation which represented by a load plate under incremental surcharge loading was stimulated to assess the soil mass deformation. The optical fibre were embedded in soil mass by layering in a horizontal direction which laid perpendicular to load direction. A comparison of numerical modeling using PLAXIS 2D and experimental works as part of this study. As a results, fibre optic is a good approach for instrumentations and monitoring for geotechnical structures as fibre optics is sensitive to the movement of the soil and fibre optic with anchorage system gave better strain measurement reading compare to without anchorage system.
Williams, William F. "Design and Full-Scale Testing of M50/P1 Bolt-Down Removeable Bollard System." Transportation Research Record: Journal of the Transportation Research Board 2672, no. 41 (December 2018): 24–33. http://dx.doi.org/10.1177/0361198118798738.
The purpose of this project was to design and test a new bolt-down bollard system that meets the requirements of American Standards for Testing Materials (ASTM) Designation F2656-15 M50/P1 impact conditions. The test installation consisted of three vertical 10-in. diameter (nominal) bollards with welded base plates bolted to a shallow reinforced concrete foundation. The foundation for this system was sized to reduce the foundation embedment. Shallow foundations are often necessary for use in cities and urban areas where utilities can conflict with deeper foundations. Standard common members and materials were used in the installation to accommodate fabrication and installation in locations all over the world. The bollards can be removed to provide access if necessary. Full-scale testing was performed on the bolt-down bollard system. The bollard system design for this project successfully met the requirements of M50/P1 with a total payload penetration of less than 1 m. The new bollard design successfully met all the performance requirements for ASTM F2656-15 M50/P1. Details of the design and testing of the bolt-down bollard system are provided in this paper. Crash-testing videos and additional information on the design and full-scale testing will be provided in the presentation.
Davidovic, Nebojsa, Zoran Bonic, Verka Prolovic, Biljana Mladenovic, and Dragoslav Stojic. "A comparative theoretical-experimental analysis of settlements of shallow foundations on granular soil." Facta universitatis - series: Architecture and Civil Engineering 8, no. 2 (2010): 135–43. http://dx.doi.org/10.2298/fuace1002135d.
The paper presents a brief description of experiment within the research project 'Theoretical and experimental analysis of interaction of shallow reinforced concrete foundations and soil for the purpose of improvement of national regulations and implementaation of Eurocode system' where in situ tests of a series of reinforced concrete foundation footing were performed, by loading until failure. As a rule, methods for calculation of shallow foundations settlement on granular soils overestimate the expected settlement, and underestimate soil bearing capacity, which results in a conservative foundation design. In order to test accuracy and reliability of the different settlements prediction methods, a comparative analysis of settlements calculated using these methods and those measured during experiment, was performed.
Kutter, Bruce L., Mark Moore, Manouchehr Hakhamaneshi, and Casey Champion. "Rationale for Shallow Foundation Rocking Provisions in ASCE 41-13." Earthquake Spectra 32, no. 2 (May 2016): 1097–119. http://dx.doi.org/10.1193/121914eqs215m.
ASCE 41-13 supports three methods of modeling the soil-structure interaction for rocking footings as components of a foundation-building system: Method 1 uses uncoupled moment, shear, and axial springs; Method 2 uses a nonlinear gapping bed of springs; and Method 3 is used for structural footings that are flexible relative to the underlying soil. New component action tables in ASCE 41-13 provide modeling parameters and acceptance criteria for nonlinear and linear analysis of shallow foundation components. The values in the component action tables for nonlinear procedures were largely based upon analysis of foundation performance in model tests on rocking foundations. The primary measure to assess foundation performance is residual settlement or uplift. The acceptance criteria for linear analysis procedures ( m-factors) were derived from the allowable rotations for nonlinear procedures. A design example is presented in an online Appendix to illustrate differences between the current and previous versions of ASCE 41 and ASCE 31.
Kim, Dong-Kwan, Hong-Gun Park, Dong-Soo Kim, and Hyerin Lee. "Nonlinear system identification on shallow foundation using Extended Kalman Filter." Soil Dynamics and Earthquake Engineering 128 (January 2020): 105857. http://dx.doi.org/10.1016/j.soildyn.2019.105857.
Kovar, James, Nauman Sheikh, Roger Bligh, Sofokli Cakalli, Taya Retterer, and Jon Ries. "Development and Testing of Structurally Independent Foundations for High-Speed Containment Concrete Barrier." Transportation Research Record: Journal of the Transportation Research Board 2675, no. 4 (January 2021): 297–307. http://dx.doi.org/10.1177/0361198120980325.
This paper presents the development and testing of single slope barriers with independent foundations that can be installed at a wide range of site conditions. The researchers developed designs of barriers with foundation systems by conducting a series of finite element simulations and performing full-scale vehicle impact tests under the American Association of State Highway and Transportation Officials’ (AASHTO) Manual for Assessing Safety Hardware ( MASH) Test Level 5 (TL-5) and Test Level 4 (TL-4) conditions. In this process, foundation designs were developed for site conditions that may require shallow foundations, or foundations that have a smaller footprint. Depending on the site conditions and the presence of underground structures, designers could select the most fitting option from these designs. Impact performance of the developed barrier and foundation systems was evaluated using full-scale finite element impact simulations under MASH TL-5 and TL-4 impact conditions. Two critical systems were selected for full-scale crash testing: a 54 in. tall single slope barrier with drilled shaft foundations, and a 36 in. tall single slope barrier with moment slab foundation. The barrier with the drilled shaft foundation system was tested to MASH Test 5-12 conditions, and the barrier with the moment slab foundation system was tested to MASH Test 4-12 conditions. Both systems performed acceptably with respect to the MASH criteria. This paper presents the various barrier and foundation designs that were developed, key results from the simulation analyses, and details of the crash testing performed on the two selected systems.
Itoh, K., X. Zeng, M. Koda, O. Murata, and O. Kusakabe. "Centrifuge Simulation of Wave Propagation due to Vertical Vibration on Shallow Foundations and Vibration Attenuation Countermeasures." Journal of Vibration and Control 11, no. 6 (June 2005): 781–800. http://dx.doi.org/10.1177/1077546305054150.
When constructing a high-speed railway system in an urban area, the reduction of the ground vibration and noise generated by train passages is a vitally important environmental consideration. In this paper we focus on the development of a centrifuge vibration testing system, which can simulate dynamic loading acting on shallow foundations. The system is used to generate vertical vibration similar to that generated by high-speed trains. The characteristics of wave propagation in a shallow circular foundation on sand are investigated. The effects of two types of barriers on vibration reduction are studied. Additionally, the impact of using vibration attenuating materials to build trackbeds is evaluated.
The diploma thesis is a project of an apartment block with a total number of 10 apartments. The building is located in the cadastral areas of Žirovnice 797154 on the numbers of parcels 653/1, 634/1, 634/2. The building is a five-storey building with four floors above the ground and one underground floor. Floors are designed as a brick system with the contact insulation. Underground floor consists of a reinforced concrete wall monolith which is based on the footings. Horizontal structures are made up of prefabricated ceramic system Miako and a reinforced concrete monolithic slab. The roof is flat and single-layer. The floors are connected by monolithic reinforced concrete staircase and an elevator which is located in the shaft.
Soelarso, Soelarso. "On the finite element analysis and design of the spider net system footing (SNSF) considering static and seismic loadings." Electronic Thesis or Diss., Compiègne, 2021. https://bibliotheque.utc.fr/Default/doc/SYRACUSE/2021COMP2656.
Cette thèse est consacrée à la compréhension approfondie du comportement mécanique de fondations superficielles de bâtiments construits sur sols relativement mous en s’appuyant sur des modélisations numériques par éléments finis tridimensionnels. Les fondations superficielles concernées permettent une diffusion et transferts de charges de type « toile d’araignée » ou « pieds de poule », fréquemment utilisés en Indonésie et appelés Spider Net System Footing (SNSF). Ces types de fondation sont adaptées aux sols mous mais aussi aux sollicitations de type tremblement de terre. Elles ont été très peu étudiées d’un point de vue scientifique. L’approche de modélisation par éléments finis en élasticité tridimensionnelle est bien adaptée aux couplages de la fondation avec la structure supérieure et avec le sol de support. Après validation des modèles éléments finis en comparant nos résultats avec des approches numériques et expérimentales existantes, nous proposons deux types d’analyses s’appuyant sur des données géométriques, mécaniques et matérielles d’une construction récente sur l’ile de Java, Province de Banten. Le premier type de modélisations permet une analyse fine du comportement statique d’une cellule de fondation avec deux poteaux, soumise à des charges verticales. Le second type de modélisations permet d’estimer les fréquences propres de vibrations libres et d’étudier le comportement d’une cellule de fondation représentative soumise à des actions sismiques, traduites en sollicitations sous charges latérales équivalentes. Les travaux incluent non seulement des analyses détaillées avec des données existantes mais aussi une proposition de dimensionnement pour projets futurs. Par ailleurs le rôle de la fondation et du sol support sur la rigidité axiale, sur les fréquences de vibration et sur la rigidité en flexion ont fait l’objet d’une attention particulière.Toutes les analyses (ou presque) ont été réalisées à l’aide des modules de la suite Hyperworks d’Altair (Hypermesh, Optistruct) This thesis is devoted to a thorough understanding of the mechanical behavior of shallow foundations of buildings built on relatively soft soils, based on three-dimensional finite element numerical modelling. The shallow foundations involved allow the diffusion and transfer of loads, as for "spider webs" or "chicken feet". They are frequently used in Indonesia and called Spider Net System Footing (SNSF). These types of foundations are suitable for soft soils but also resistant under earthquake actions. They have little been studied from a scientific point of view. The finite element modeling approach in three-dimensional elasticity is well suited to take into account the couplings of the foundation with the upper structure and with the supporting soil. After validation of our finite element models by comparing our results with existing numerical and experimental ones, we propose two types of analyses based on geometric, mechanical and material data extracted from of a recent construction on the island of Java, Province of Banten. The first type of analyses allows fine relevant modelling of the static behavior of a foundation cell with two columns, subjected to vertical gravity loads. The second type of modelling makes it possible to estimate the frequencies of free vibrations and to study the behavior of a representative foundation cell subjected to seismic actions, under equivalent lateral loads via the Elastic Response Spectrum Approach. The present work includes not only detailed analyses with existing data but also a design proposal for future projects. Special attention is also paid to the role of the foundation and the supporting soil on the axial rigidity, vibration frequencies and bending stiffness. Almost all finite element analyses have been done using the Hyperworks software from Altair (Hypermesh, Optistruct)
Holemy, Ondřej. "Víceúčelová spotrovní hala." MasterThesis, Vysoké učení technické v Brně. Fakulta stavební, 2015. http://www.nusl.cz/ntk/nusl-227187.
The master‘s thesis concerns about the freestanding multipurpose sport hall with a base for sportsmen and spectators and its associated sport and regeneration centre. The object is situated in a city district Brno Bohunice. The designed building is divided into a single storey multipurpose sport hall and an outbuilding with two above-ground floors and a partial third floor above the entrance part of the building. Object’s plan shape forms a rectangle with recessed entrance part. The load-bearing structure consists of a combined column and wall construction system. The main multipurpose hall is roofed with arched glulam laminated trusses, which are supported by steel columns covered by sandwich panels. The outbuilding’s vertical load-bearing structure is formed by clay blocks. The horizontal load-bearing structure is formed by prestressed concrete floor slab. The building is based on shallow foundations. The object is designed to be barrier-free for sportsmen and visitors as well.
Kolesa, Jiří. "Polyfunkční dům ve Strakonicích." MasterThesis, Vysoké učení technické v Brně. Fakulta stavební, 2017. http://www.nusl.cz/ntk/nusl-265574.
The subject of this thesis is the design and project documentation of a new multifunctional house in Strakonice. The building has four floors, without basement, and is located on a slightly sloping land in the suburban part of the town of Strakonice. It is based on shallow foundations and covered with a flat roof. It is a transverse wall structural system, build with clay block masonry, with the semi-assembled ceiling structures of ceramic and concrete beams and inserts. It is conceived as a double-aisle layout. The ground floor of each wing consists of the establishment of shops and house facilities. The overground floors are designed as six residential units of varying size category. Both tracts have separate entrances to both the residential portion and to individual businesses. The building is designed from traditional building materials. In addition to the architectural construction and civil-engineering design, a part of this project is also a fire safety design and an assessment from the perspective of building physics.
Vandrovec, Aleš. "Horský hotel." MasterThesis, Vysoké učení technické v Brně. Fakulta stavební, 2014. http://www.nusl.cz/ntk/nusl-226604.
Master’s thesis theme is mountain hotel project. The hotel has one lower basement and four aboveground floor. It has trditional look and the roof is double-pitched. Floor projection looks like letter "L". Main part has measurements 25,3 x 14,1 m and it has four floor. Extension is on northwest side of main part. It has measuremnts 11,85 x 9,5 m and three floor. Facede of basement and first floor is from stone facing mansory. Facade od second floor of main patr of buildings id timbered looks like curb. Third and fourth floor are attic, gable is vertical timbered. Facade of second floor of extension is plaster on ETICS. The gable od extension is vertical timbered. Roof covering is alpen shingle from larch wood. Foundations of house are shallow. The construction system is walled. The lower basement is built from masonry BS Klatovy BD30 and other wall are from masonry Porotherm . Floor structures are from monolithic reinforced concrete, thickness 220 mm. House stairs are prefabricated double-flight. Partition wall are mostly built from mansory Porotherm 11,5 P+D. Lintols above windows and doors in facadeare made by reverse of floor slab and inside of disposition are made by ceramics lintols Porotherm. Floor structures are floating with impact insulation in whole house. In living rooms wear layers are from oak parquet block and in common rooms, toilets, bathrooms and technical rooms is ceramics paving. Wall’s surfaces are made from patent plaster and in lower basement are made from two-coat work with white coat. Toilets and bathrooms are tilled with ceramic tiles. All distributions of building equipment are covered with gypsum plasterboard ceiling. All windows and doors in facade are made by wooden profile Solid comfort SC78 and glazed by triple glazing unit (Uw,max=0,9 W/m2.K), exception is main entrance door, It is made by aluminum profile and it is automatically opened.
Книги з теми "Shallow foundation system":
Tiwari, Sandip. Semiconductor Physics. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780198759867.001.0001.
A graduate-level text, Semiconductor physics: Principles, theory and nanoscale covers the central topics of the field, together with advanced topics related to the nanoscale and to quantum confinement, and integrates the understanding of important attributes that go beyond the conventional solid-state and statistical expositions. Topics include the behavior of electrons, phonons and photons; the energy and entropic foundations; bandstructures and their calculation; the behavior at surfaces and interfaces, including those of heterostructures and their heterojunctions; deep and shallow point perturbations; scattering and transport, including mesoscale behavior, using the evolution and dynamics of classical and quantum ensembles from a probabilistic viewpoint; energy transformations; light-matter interactions; the role of causality; the connections between the quantum and the macroscale that lead to linear responses and Onsager relationships; fluctuations and their connections to dissipation, noise and other attributes; stress and strain effects in semiconductors; properties of high permittivity dielectrics; and remote interaction processes. The final chapter discusses the special consequences of the principles to the variety of properties (consequences of selection rules, for example) under quantum-confined conditions and in monolayer semiconductor systems. The text also bring together short appendices discussing transform theorems integral to this study, the nature of random processes, oscillator strength, A and B coefficients and other topics important for understanding semiconductor behavior. The text brings the study of semiconductor physics to the same level as that of the advanced texts of solid state by focusing exclusively on the equilibrium and off-equilibrium behaviors important in semiconductors.
Частини книг з теми "Shallow foundation system":
Abbas, Hussein S., Rami M. El-Sherbiny, and Abdelsalam M. Salem. "Numerical Analysis of Mechanically Stabilized Earth Walls in Hybrid Retaining Wall Systems." In Advanced Research on Shallow Foundations, 249–64. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-030-01923-5_18.
Giarlelis, Christos. "Geotechnical Aspects of Structural Failures." In Characteristic Seismic Failures of Buildings, 149–87. Zurich, Switzerland: International Association for Bridge and Structural Engineering (IABSE), 2019. http://dx.doi.org/10.2749/sed016.149.
<p>Strong seismic shaking is recognized as the direct cause of structural failures. In many cases, however, the factor that initiates the structural damage is ground failure or ground displacement. This chapter deals with the identiﬁcation of all geotechnical related structural failures. Surface fault rupture has been a well-acknowledged cause of failures of structures built across or near the fault, which are increasing in frequency as the man-made environment constantly expands to new areas. Seismically induced rockfalls, landslides and slope failures have also been associ-ated with major disasters with an increasing frequency in some cases due to an expanding popu-lation, which encroach on areas with landslide risk or in other cases as result of the destruction of the natural environment (vegetation and water routes), which have protected these slopes in the past. Foundation damage may be a result of failure of shallow foundations or piles. In addition, although liquefaction and ground settlement are technically part of foundation failures, they are usually treated as separate, special cases. Retaining wall structures, usually considered as simple systems, may display a complex behaviour, which can be related to extensive seismic failures. Finally, not taking into account soil–structure interaction (SSI) may have a detrimental effect on the dynamic response of structures. Although SSI may never be the direct cause of a structural failure, it has proven to be, in several cases, the underlying reason for the analysis misconception that led to the failure.</p>
"shallow mat (foundation) (system)." In Dictionary Geotechnical Engineering/Wörterbuch GeoTechnik, 1212. Berlin, Heidelberg: Springer Berlin Heidelberg, 2014. http://dx.doi.org/10.1007/978-3-642-41714-6_192679.
Toh, J. C. W., and M. J. Pender. "Design approaches and criteria for earthquake-resistant shallow foundation systems." In Soil-Foundation-Structure Interaction, 173–80. CRC Press, 2010. http://dx.doi.org/10.1201/b10568-22.
Orense, R. P., Y. Hong, and Y. Lu. "Numerical simulation of liquefaction effects on adjacent buildings with shallow foundations." In Seismic Performance of Soil-Foundation-Structure Systems, 25–35. CRC Press, 2017. http://dx.doi.org/10.1201/9781315161563-3.
Battisti, Danielle. "The End of the National Origins System and the Limits of White Ethnic Liberalism." In Whom We Shall Welcome, 202–34. Fordham University Press, 2019. http://dx.doi.org/10.5422/fordham/9780823284399.003.0008.
This chapter explores the ideological foundations of Italian American attacks on the National Origins System and their corresponding defense of a regulatory system based primarily on the principle of family reunification in the 1960s. Italian Americans articulated both a secular liberal critique of the National Origins System and one based on Catholic social thought. However, there were limits to their particular brand of liberalism. Italian Americans also continued to employ the rhetoric of immigrant “contributionism” to make their case. In doing so, they continued to argue that certain immigrant or ethnic groups were worthy of immigration and citizenship opportunities not because all individuals deserved the same basic legal and political rights but because those groups had somehow earned those rights through past demonstrations of “good” or accepted behaviors.
"Offshore systems Installation resistance and bearing capacity of a shallow skirted foundation in clay." In Physical Modelling in Geotechnics, Two Volume Set, 1035–42. CRC Press, 2010. http://dx.doi.org/10.1201/b10554-171.
Beris, Antony N., and Brian J. Edwards. "Equilibrium Thermodynamics." In Thermodynamics of Flowing Systems: with Internal Microstructure. Oxford University Press, 1994. http://dx.doi.org/10.1093/oso/9780195076943.003.0008.
The ideas which we shall present in the remainder of this book are intimately connected with thermodynamics. In order to describe the various transport processes in structured continua, one must first build a solid foundation of equilibrium thermodynamics upon which to base further development. In approaching transport phenomena from an energetic viewpoint, one must first define what is meant by various thermodynamic variables as, for example, the temperature and pressure, in terms of the primitive variables used to characterize the system under investigation. In this chapter, we present a brief overview of equilibrium thermodynamics tailored to the needs of this book. Specifically, we want to define explicitly the thermodynamic quantities which are used in subsequent chapters. For clarity and completeness, we shall re-derive, rather than merely state, some of the standard thermodynamic relationships. Of course, the experienced reader may proceed directly to the next chapter and use this chapter as a reference to notation as the need arises. The starting point for our discussion of equilibrium thermodynamics is the axiomatic foundation of the description of macroscopic equilibria on certain fundamental principles. First, the macroscopic equilibrium of a closed system is completely described through the specification of a number of extensive (i.e., proportional to the total mass or volume of the system, and additive between systems) or intensive (i.e., independent of the total mass or volume of the system) parameters. This is a very important point which is usually overlooked in the traditional thermodynamic development. The extensive nature of the primary variables of the system introduces an additional relationship which acts on the allowed variations of the differentials, which, as we shall see, is tantamount to the Gibbs/Duhem relation. This implies, as we shall demonstrate in §4.3, that the density formalism, where every extensive quantity is reported on a unit volume basis, is a much more natural framework for describing the system in that it avoids a number of pitfalls of the traditional formalism.
Тези доповідей конференцій з теми "Shallow foundation system":
Gueydon, Sébastien, and Sam Weller. "Study of a Floating Foundation for Wind Turbines." In ASME 2012 31st International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/omae2012-83389.
Offshore wind farms are currently located predominantly in shallow water as it is possible to cost effectively install bottom fixed offshore turbines. Where shallow water sites are not available, floating offshore turbines could be a better solution than bottom fixed turbines. Currently three main concepts are promoted for the design of a floating wind turbine: a ballast stabilized floater (i.e. spar), a buoyancy stabilized floater (i.e. barge or semi-submersible) or a mooring stabilized floater (tension leg platform). In April 2011 the DeepCWind consortium visited MARIN to carry out model tests in the offshore wave basin with these three types of floating wind turbine platform. This paper reports a numerical study of a wind turbine supported by a semi-submersible floater. The response of the floating system to wind and wave conditions is compared to physical measurements at 1:50 model scale. The outcome of these comparisons is discussed in the conclusions of this paper.
Omar, Tarek A., and Nabih E. Bedewi. "New Shallow Foundation Security Barriers for Urban Applications: FEA and Certified Actual Crash Test." In ASME 2009 International Mechanical Engineering Congress and Exposition. ASMEDC, 2009. http://dx.doi.org/10.1115/imece2009-12203.
Providing an accurate and reliable design or analysis of complex physical security systems has been a great challenge for several years. To meet this challenge, the latest and most advanced engineering techniques proved to be necessary. Among them is the Finite Element Analysis (FEA) computational method. FEA is recognized today within the engineering and scientific community to be a very powerful tool in solving the most complex structural analysis, crash and impact-related problems. Due to the significant improvements in computer technology and software developments, FEA can now provide excellent support to the design, analysis, evaluation and improvement of all security barriers. In the current research, a new shallow-foundation bollard system design has been conceived and analyzed using nonlinear FEA. This design is appropriately suitable for urban applications since its foundation is a mere 18 inches deep and can be installed within a few hours. Further optimization led to the utilization of the most appropriate commercial steel-structural elements with the objective of reducing material, manufacturing and installation costs. The system has proven to be capable of sustaining severe impacts by spreading a portion of the induced energy throughout the entire structure and the supporting soil/concrete. This was possible through a process of FEA iterations that resulted in the refinement of the initial bollard concept. Subsequently, a five-bollard full-scale module was constructed and tested under K12 impact conditions as defined by the Department of State (DOS) guidelines (SD-STD-02.01). According to the DOS guidelines, a K12 rated barrier must be able to stop a 15,000 lb single unit truck at an impact speed of 50 mph. The system successfully stopped the truck with negative cargo penetration and less than 5 inch bollard deformation. In the final step, the FE model of the tested bollard system was validated by simulating the crash at the exact test speed (47.4 mph). The FE simulation results showed excellent correlation with the actual test output.
Hossain, M. Kabir, Han Shi, Basel Abdalla, and Markella K. Spari. "Understanding Hybrid Subsea Foundation Design." In ASME 2015 34th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/omae2015-42214.
Hybrid subsea foundations (HSF) are combined foundation systems of mudmats and piles. The primary motivation of combining these two foundation types is to provide greater resistance to large horizontal loads in addition to vertical loads, for which use of mudmats alone will require it to be of impractically large size. The contribution from the piles in the lateral capacity helps to limit the size of the mudmat, which is critical in subsea environment. In a brownfield situation, this is sometimes a hard limit with only limited space available to place a new mudmat in the existing field layout. Also, in some cases, the HSF may prove to be a more economical option for resisting large horizontal loads compared to, for example, to suction piles. While the authors are aware of some scattered project-specific design and use of subsea mudmat-pile hybrid foundations by individual contractors and operators, there is no industry-wide publicly known best practice currently available. These designs of HSF appear to be generally based on simplified analytical approach that require superimposition of conventional shallow and deep foundation capacity calculation methods, hence violates the static and kinematic compatibility requirements fundamental for a sound and robust prediction procedure. This paper attempts to provide some insight into the behavior of mudmat-pile foundations as a hybrid integrated system numerically using finite element modeling and analysis (FEA). The interactions between the mudmat and the piles in an HSF are complex and hence a FEA-based approach is considered most suitable. The FEA model in this study included the mudmat, the corner piles, the pile-mudmat connections and the seabed soil. Sensitivity of the HSF capacity to the size of the piles (length and diameter), the connection type of the piles to the mudmat, and the number of piles are selectively investigated and the results presented. Based on these results some pertinent observations relevant to design of HSFs are also given. While the study is of limited scope, it offers important insights into the effects of the primary design variables on HSF’s capacities. Therefore, the authors hope the information herein will be of benefit to practicing subsea engineers who might have to face choices to consider mudmat-pile hybrid foundations as a real option for their projects.
Leppla, Steffen, and Arnoldas Norkus. "ON APPLICATION OF COMBINED PILE-RAFT FOUNDATIONS FOR ROAD STRUCTURES." In 11th International Conference “Environmental Engineering”. VGTU Technika, 2020. http://dx.doi.org/10.3846/enviro.2020.829.
Roads and road infrastructure systems are designed to satisfy ultimate and serviceability conditions under long-term actions caused by transport loadings and environmental effects. Selected design solutions must be safe and rational in terms of construction and maintenance costs. In cases when weak or soft soil layers of natural soil profiles are shallow and/or the traffic loads are very large, the Combined Pile-Raft Foundation (CPRF) is the economical road and railway structure design solution. Application of CPRF is cheaper geotechnical solution comparing with soil change or usual piled foundation alternatives. The development of this system is based on the analysis of relevant mechanical properties of soil layers and the evaluation of the soil-structure interaction. The soil-structure interaction is of highest importance allowing proper evaluation of load bearing resistance and deformation transmitted by raft and piles to soil layers. The soil and foundation system usually is subjected by loadings, resulting elastic-plastic resistance range. Therefore, relevant nonlinear physical laws due to the stress levels are used. The paper purpose is summarizing the experience of application of Combined Pile-Raft Foundations used in road and railway construction and bridge engineering.
Harris, John M., Richard J. S. Whitehouse, and James Sutherland. "Marine Scour and Offshore Wind: Lessons Learnt and Future Challenges." In ASME 2011 30th International Conference on Ocean, Offshore and Arctic Engineering. ASMEDC, 2011. http://dx.doi.org/10.1115/omae2011-50117.
The drive for developing marine offshore renewables has led to specific requirements for scour hazard assessment relating to the associated foundation structures and the cabling necessary for in-field transmission and power export. To date within the United Kingdom (UK) a number of demonstrator projects have been constructed covering wind, wave and tidal generation. However, only offshore wind has been developed at large-scale at present as part of two rounds of commercial development of offshore wind farms (OWFs). In June 2008, The Crown Estate, responsible for licensing seabed use, announced proposals for a third round of offshore wind farms to develop an additional 25 GW of energy to the 8 GW already planned for under Rounds 1 and 2. The size of these Round 3 developments will vary, but the largest of these zones will involve the construction of around 2500 seabed foundation structures. Under Round 1 and 2 developments monopile and jacket type foundations have been used, although several other European (non UK) wind farms have been built using gravity base foundations. For a wind turbine the foundations may account for up to 35% of the installed cost. Therefore, one of the future challenges for large volume installation of offshore wind is the control and minimization of these costs. For tidal energy devices one of the principal requirements for many of the devices proposed is their placement in areas of strong tidal energy, and this has implications not only for the stability of the foundation option, but also for the construction methodology. Similarly wave energy devices are designed to be located in shallow, coastal environments as either floating or bottom mounted systems. These devices, by design, are intended to be located in environments with strong wave action. This may be substantial during storm events, which has implications for the integrity of the anchoring system keeping the wave device on station or the design of the device if it is seabed mounted. This paper will explore the lessons learnt from existing offshore wind farm developments as this represents the principal body of collected monitoring data. Using these data the paper will outline some of the challenges facing the offshore renewable industry in respect of the foundation designs and specifically the requirements for scour hazard assessment using the combined experience from those developments currently operational or under construction.
Cruz Roque, Diego, Jaime Nu´n˜ez Farfa´n, Pro´coro Barrera Nabor, and Wilbert Koh Cambranis. "Integration of Field Investigation to Evaluate the Degradation of the Bearing Capacity of Platform Foundations Due to the Gas Presence." In ASME 2003 22nd International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2003. http://dx.doi.org/10.1115/omae2003-37257.
Natural Gas emanations at the Campeche Sound in the Gulf of Mexico have caused in some cases the failure of soils under existent platforms. The gas pockets that were detected in shallow geophysical surveys prior to the platform installations have migrated invading the area of some platforms. The presence of these shallow gas pockets and sudden gas emanations (blow out) is a cause of concern regarding the safety of the existent and planned platforms. An investigation was carried out in order to assess the effect of the gas emanations and the presence of the shallow gas on the safety of the platforms. The investigation included a desk study with the purpose of integrating all relevant information from the reservoir and up to the sea bed with the participation of all the disciplines involved. On these bases, a field investigation was planned, to confirm the results of the desk study. This investigation included the application of several new techniques in the exploration field. The field investigation included geophysical, geotechnical and geochemical exploration, as well as the installation of a monitoring system to better understand the complex gas effects on the structures foundation. A 3D high resolution seismic survey was used to investigate the origin and dimensions of the shallow gas pockets. Te evaluation of the effects of shallow gas and hydrocarbon deposits on the existing and proposed structures in the Cantarell field was achieved through an integrated analysis of the geophysical data, in situ measurement of pore pressure, in situ and laboratory geotechnical analysis of gas in soil boring profiles, special static and cyclic laboratory testing on hydrocarbon saturated soils, and special cyclic testing on gas-saturated granular soils. The study shows that the current levels of pressure in the hydrocarbon pockets are not expected to affect the existent structures safety; however, as it has happened in the past, it is possible that pressure could build up and cause a sudden gas expulsion affecting existing platforms. Taking this in consideration a monitoring system was installed in order to measure the pressurization of the foundation zone strata that could result in weakening of the soil response affecting the structure stability.
Zhao, Yuna, Zhengshun Cheng, Zhen Gao, and Torgeir Moan. "Effect of Foundation Modeling of a Jack-Up Crane Vessel on the Dynamic Motion Response of an Offshore Wind Turbine Blade During Installation." In ASME 2018 1st International Offshore Wind Technical Conference. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/iowtc2018-1010.
Nowadays, there is an increasing demand for use of jack-up crane vessels to install offshore wind turbines. These vessels usually have shallow soil penetration during offshore crane operations because of the requirement of frequent repositioning. The soil-structure interaction should thus be properly modeled for evaluating the motion responses, especially at crane tip at large lifting height. Excessive crane tip motion affects the dynamic responses of the lifted components and subsequently affects the safety and efficiency of operations. The present study addresses the effects of soil behaviour modeling of a typical jack-up crane vessel on the dynamic motion responses of a wind turbine blade during installation using a fully coupled method. The coupled method account for wind loads on the blade and the vessel hull, wave loads on the vessel legs, soil-structure interaction, structural flexibility of the vessel legs and crane, and the mechanical wire couplings. Three models for the soil-leg interactions and two soil types are considered. The foundation modeling is found to have vital effects on the system dynamic motion responses. The characteristics of system motion differ under different types of soil. Compared to the combined linear spring and damper model, the simplified pinned and fixed foundations respectively lead to significant overestimation and underestimation of the motion responses of the blade during installation by jack-up crane vessels. To ensure safe and efficient offshore operations, detailed site specific soil properties should be used in numerical studies of offshore crane operations using jack-up crane vessels.
Pereira, Mauricio, Maria Fernanda Contreras, and Carlos Vergara. "Soil-Pipeline Interaction Modeling and Assessment in Unstable Slopes." In ASME 2013 International Pipeline Geotechnical Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/ipg2013-1929.
Due to their length, oil and gas pipelines usually face different geotechnical problems along their routes (fast or slow, shallow or deep landslides) that impact the pipe integrity. In the current state of practice, this problems are analyzed considering the system as a beam on elastic foundation (Winkler type models), in which the loads on the pipe (e.g. internal pipe pressure and geostatic loads) are studied independently. A more realistic description of the soil-pipe interaction phenomenon that allows the prediction and explanation of the pipe failures found in the practice requires more advanced methodologies, involving the constitutive behavior of soil and pipe and the combined effect of different types of loads. In order to assess in a better way the soil-pipe interaction problem in landslides, this paper presents a 3D numerical model of the system, including the combined effect of different loads (such as landslide loads, geostatic loads and pipe internal pressure). The results obtained with the model were validated against real field measures in the OCENSA pipeline system and are expressed as soil displacement versus pipe strain relations. These relations are being used successfully in the evaluation of the behavior of the pipeline in unstable slopes, resulting in an important tool in the OCENSA pipeline integrity program.
Newgard, J. T., and J. S. McCartney. "Long Term Cyclic Axial Loading System for Shallow Anchors." In International Foundations Congress and Equipment Expo 2021. Reston, VA: American Society of Civil Engineers, 2021. http://dx.doi.org/10.1061/9780784483404.020.
Black, Jared L. "Using Vibration Measurements to Assess Structural Integrity." In ASME 2009 28th International Conference on Ocean, Offshore and Arctic Engineering. ASMEDC, 2009. http://dx.doi.org/10.1115/omae2009-79144.
Structural vibration monitoring can aid in assessing offshore platform structural integrity. The method utilizes topside acceleration measurements to detect the platform’s natural periods of vibration; the periods depend only on platform weights (mass) and resistance (stiffness). If the platform’s natural period increases over time, in the absence of a change in mass, it can indicate a loss of structural integrity. The vibration survey utilizes a portable monitoring system, which includes sensitive low frequency accelerometers. The above water monitoring provides information on the below water structural integrity; the method is very low cost when compared to diver or ROV surveys. Examples of structural monitoring surveys are presented, including the following: verification that a platform remained fit for purpose despite having its foundation disturbed by a shallow gas release, two cases of using surveys to confirm jacket stiffness recovery following repairs of structural damage caused by Gulf of Mexico hurricanes and evaluation of a minimal platform after a heavy compressor was installed. The development of a natural period database is reviewed. The database, covering 95 platforms in Asian waters, was developed to reduce inspection costs and aid in life extension reviews, as well as providing quick integrity assessments should a tropical cyclone cross the production area.