Academic literature on the topic 'Protective Concrete Structures'
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Journal articles on the topic "Protective Concrete Structures"
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Korolko, Serhiy, and Bohdan Seredyuk. "Nanomodified rapid hardening concretes reinforced with dispersed basaltic fibers." Military Technical Collection, no. 24 (May 20, 2021): 57–63. http://dx.doi.org/10.33577/2312-4458.24.2021.57-63.
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The article considers modern perspectives and directions of using fast – hardening high – strength concretes for protection against striking factors of action of different types of weapons. It is shown that the use of concrete materials in weapons and military equipment is one of the important components of defense structures and protective fortifications during hostilities as platoons and bases, and structures for the protection of civilians. The possibility of obtaining such concretes for the creation of special purpose fortifications is shown. Developed concrete structures have increased strength and impact resistance to high-speed impact. Due to the reinforcement of the concrete structure with mineral and chemical additives and ultrafine fibers, high rates of early strength, viscosity, crack resistance and impact resistance are achieved. The paper presents the main indicators of water consumption, strength and impact resistance of high-strength concrete. The results of the experimental study of samples of the destroyed concrete elements are presented and the corresponding conclusions concerning the use of various types of fibers for reinforcement of such concretes and increase of their crack resistance by basalt fibers are made. It is shown that a high-strength concrete with high construction and technical performance can be successfully used to create protective fortifications and fortifications for special purposes.
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Kobayashi, Kazusuke. "Protective Coating for Concrete Structures." Concrete Journal 23, no. 8 (1985): 20–23. http://dx.doi.org/10.3151/coj1975.23.8_20.
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Kostyuk, Tetiana, Andriy Plugin, Dmytro Plugin, Oleksandr Bondarenko, and Olena Dedenova. "MECHANISM FOR CREATING A CEMENT COMPOSITE WITH ENHANCED HYDROPHYSICAL AND RADIATION PROTECTION PROPERTIES." Collection of Scientific Works of the Ukrainian State University of Railway Transport, no. 206 (December 11, 2023): 101–11. http://dx.doi.org/10.18664/1994-7852.206.2023.296647.
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In modern conditions, the environmental component of building protective materials is guaranteed by the creation of composites capable of protecting underground and above-ground parts of buildings and structures in flooded areas from the filtration of radiation-contaminated water, industrial wastewater, radon, etc. Therefore, the problem of developing modern, including radiation-protective materials for the construction industry is urgent. Concrete is a good moderator and absorber of fast neutrons and intensively absorbs gamma radiation. Concrete consists of cement, sand and gravel. Cement consists mainly of oxides of various elements (Ca, Si, Al, Fe) and contains light elements. Portland cements, slag Portland cements and alumina cements are used as binders for the preparation of particularly heavy protective concrete. In special concretes, the most effective binder can be a substance that, as a result of hardening, adds a large amount of water (to increase the hydrogen content of the concrete). Such a substance is calcium hydrosulfoaluminate. Recent studies have shown that very effective radiation protection materials are materials in the form of polydisperse systems containing ultrafine particles (UFP) less than 1 micron in size. However, the difficulty is to distribute the ultrafine particles evenly throughout the material volume, which dramatically reduces its protective functions.The work resulted in the development of a cement composite with enhanced hydrophysical and radiation protection properties, which were achieved by, firstly, modifying the cement binder with chemical additives that facilitated the synthesis of crystalline hydrates with a high water content. Secondly, polydisperse systems in the form of ferruginous quartzite were added to the composition, where micron-sized iron particles were embedded in quartzite, which contributed to the uniform distribution of micron-sized iron particles in the volume of the composite. Physicochemical studies of cement stone hydration products were carried out by X-ray diffraction, differential thermal and electron microscopic analyses. The developed composition of fine-grained concrete has high performance and hydrophysical properties, provides protective properties against radiation due to components containing heavy and light atoms, which may allow the use of this material to protect building structures, buildings and structures.
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Klingsch, Eike Wolfram, Andrea Frangi, and Mario Fontana. "Fire Protection of High-Performance Concrete Using Protective Lining." Applied Mechanics and Materials 82 (July 2011): 758–63. http://dx.doi.org/10.4028/www.scientific.net/amm.82.758.
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The paper presents results of experimental and numerical analyses on the fire behavior of concrete elements protected by sprayed protective linings. Particular attention is given to high- (HPC) and ultrahigh performance concrete (UHPC), as HPC and UHPC tend to exhibit explosive spalling in fire due to low porosity. The results provide basic input data for the development of simplified rules for the fire design of concrete structures protected by sprayed protective linings.
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Årskog, V., K. Borgund, and Odd E. Gjørv. "Effect of Concrete Hydrophobation against Chloride Penetration." Key Engineering Materials 466 (January 2011): 183–90. http://dx.doi.org/10.4028/www.scientific.net/kem.466.183.
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For concrete structures in chloride containing environments, hydrophobic surface treatments are often used as an additional protective measure for protecting the embedded steel against corrosion. In recent years, silane-based hydrophobic agents that can be used as concrete admixtures for making the whole concrete hydrophobic have also been introduced. In the present paper, the protective effectiveness of such an admixture against chloride penetration has been investigated. For comparison, some field investigations on the effectiveness of a traditional surface hydrophobation of two concrete harbor structures based on similar products are also briefly reported.
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Bilyk, S. І., and А. S. Bilyk. "COMPARISON OF THE METHODS OF PENETRATION OF THE ENEMY'S AIR ATTACK MEANS IN REINFORCED CONCRETE STRUCTURES OF CRITICAL INFRASTRUCTURE FACILITIES PROTECTION." Modern structures of metal and wood, no. 28 (August 2024): 75–84. http://dx.doi.org/10.31650/2707-3068-2024-28-75-84.
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On the basis of the literature review, trends in the development of studies of engineering protection of critical infrastructure objects were revealed. The review of scientific works revealed the direction of improving the physical and mechanical properties of building protective structures. It is noted that large-scale experimental and theoretical studies of reinforced concrete structures and reinforced concrete protective plates with the use of fiber were carried out.
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Kamaitis, Zenonas. "MODELLING OF CORROSION PROTECTION FOR REINFORCED CONCRETE STRUCTURES WITH SURFACE COATINGS/GELŽBETONINIŲ KONSTRUKCIJŲ SU PAVIRŠINĖMIS DANGOMIS KOROZINĖS APSAUGOS MODELIAVIMAS." JOURNAL OF CIVIL ENGINEERING AND MANAGEMENT 14, no. 4 (2008): 241–49. http://dx.doi.org/10.3846/1392-3730.2008.14.23.
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Corrosion is a serious problem for the durability of reinforced concrete structures. These structures need to be protected from corrosion in a variety of exposure conditions ranging from atmospheric to continuous immersion in water or chemicals. One of the ways to protect reinforced concrete structures from corrosion is to use protective coatings. The surface barriers of non‐degradable materials are able to slow down considerably the rate of deterioration of concrete structures and to overcome most durability problems associated with external attack. Design of durability of concrete structures with protective coatings needs to be established. In this paper a general framework for service life prediction and reliability evaluation of anticorrosion protective system (CPS), which is represented by protective surface barrier, concrete cover, and steel reinforcement itself of reinforced concrete structures, is presented. This approach is based on a reasonable understanding of the main degradation processes of all components ensuring protection ability and durability of concrete structures. The effect of repair of CPS components on extending the service life of a whole protective system is considered. Numerical example for reliability verification of CPS is also given. Santrauka Korozija yra svarbi gelžbetoninių konstrukcijų ilgaamžiškumo problema. Gelžbetonines konstrukcijas būtina apsaugoti nuo korozijos įvairiomis sąlygomis, pradedant nuo atmosferos iki nuolatinio mirkymo vandenyje ar chemikaluose. Vienas iš apsaugos būdų yra polimerinės apsauginės dangos. Atsparus paviršinis barjeras gali labai sulėtinti gelžbetonio irimą ir išspręsti daugelį problemų, susijusių su išorine aplinka. Reikia sukurti gelžbetoninių konstrukcijų su apsauginėmis dangomis projektavimo metodiką. Straipsnyje nagrinėjama antikorozinės apsauginės sistemos, susidedančios iš paviršiaus apsauginio barjero, apsauginio betoninio sluoksnio ir pačios plieninės armatūros, patikimumas ir spėjamas gyvavimo laikotarpis. Šis modelis remiasi apsauginio barjero, betonio sluoksnio ir armatūros irimo procesų samprata. Skaitinis pavyzdys rodo antikorozinės apsauginės sistemos patikimumo patikrą.
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HAIKO, H. I., A. L. HAN, V. V. VAPNICHNA, and I. O. MATVIICHUK. "ANALYSIS OF PROGRESSIVE DESIGN SOLUTIONS FOR UNDERGROUND CIVIL PROTECTION STRUCTURES." Bridges and tunnels: Theory, Research, Practice, no. 26 (November 26, 2024): 31–40. http://dx.doi.org/10.15802/bttrp2024/315286.
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Purpose. Analysis of progressive types and structures of underground civil defense structures against air strikes, development and implementation of innovative solutions in the practice of construction and reconstruction of protective objects, especially for cases of direct impact of ammunition into the perimeter of an underground structure. Methodology. Comparative analysis and differentiation of protective structures, improved methods of renovation and application of existing underground facilities for a new (protective) purpose; methods of finding new technical solutions for the protection of shallow structures from air strikes. In the conditions of Russia's large-scale aggression against Ukraine, the problem of protecting the population from possible air strikes takes priority, and the use of underground space forms the main direction of engineering solutions. Findings. A promising direction for the development of the use of the subway as a civil defense storage facility is the renovation and arrangement of tunnels not involved in transport and auxiliary operations, which can significantly increase the capacity of such storage facilities and improve the living conditions of people. Methods of renovation and arrangement of subway tunnels, cost-effective constructive solutions and methods of construction of civil defense structures. Originality. The differentiation of underground protective objects was carried out according to the principle of protection against air strikes in cases of direct and indirect (remote from the perimeter of the underground structure) pot-raping ammunition. For the first time, frameworks made of soil concrete, formed by jet cementation of soils, are considered as retaining structures capable of perceiving, in particular, dynamic (explosive) loads. Practical value. Effective introduction into the practice of underground construction of advanced technical solutions and methods of renovation and adaptation to the storage functions of existing underground structures, construction of protective structures using innovative methods, in particular, using soil concrete. Wide development of construction techniques of jet cementation of soils gives reason to believe that mastering a new method of erecting underground structures from soil concrete will not cause complications and will not take much time.
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van Breugel, K. "Establishing performance criteria for concrete protective structures." Structural Concrete 2, no. 3 (2001): 133–43. http://dx.doi.org/10.1680/stco.2001.2.3.133.
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Zhu, Xingji, Can Zhao, Longjun Xu, Yujin Wang, Shibin Lin, and Guochen Zhao. "Numerical Integration Study of Penetration and Blasting Damage for Composite Underground Protective Structure with Reinforcement Layers." Buildings 14, no. 6 (2024): 1848. http://dx.doi.org/10.3390/buildings14061848.
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In response to the increasing threat of powerful earth-penetrating weapons, underground protective structures typically employ composite structural systems with reinforced steel layers. However, current numerical studies often simplify the entire structural system to plain concrete when assessing damage effects, and penetration and blasting processes are treated separately using a restart method. In this paper, we adopt an integrated simulation approach to analyze the resistance performance of composite protective structures with reinforcement layers. The results reveal significant differences in failure modes between plain concrete and reinforced concrete protective structures. The diameter of the steel bars and the spacing between mesh layers notably impact the penetration and blasting damage. Based on the results of a parameter analysis, we propose a method for optimizing the design of reinforcements in composite underground protective structures. The results of the study show the following: (1) The penetration and blast damage patterns of EPWs on plain concrete and composite protective structures with reinforcing mesh are significantly different. Compared to the plain concrete layer, the composite protection structure can effectively resist the damage of EPWs. (2) With the increase in reinforcement diameter, the decrease in reinforcement mesh spacing, and the increase in reinforcement dosage, the penetration depth gradually decreases; the amount and range of the blast damage also decrease accordingly. (3) Under the condition of the same reinforcement ratio, reducing the number of layers of reinforcement mesh, increasing the diameter of reinforcement, and configuring the reinforcement on the top of the protective structure as much as possible can improve the performance of the protective layer against penetration. At the same time, the reasonable arrangement of the reinforcement mesh can also enhance the ability of the protective structure to resist blasting damage.
Dissertations / Theses on the topic "Protective Concrete Structures"
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Hansson, Håkan. "Warhead penetration in concrete protective structures." Licentiate thesis, KTH, Betongbyggnad, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-48009.
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The analysis of penetration of warheads in concrete protective structures is an important part of the study of weapon effects on protective structures. This type of analysis requires that the design load in the form of a warhead is determined, and its characteristic and performance within a protective structure is known. Constitutive equations for concrete subjected to weapon effects have been a major area of interest for a long time, and several material models for concrete behaviour are developed. However, it is not until recent years that it has been possible to use finite element (FE) analyses to simulate the behaviour of concrete targets during projectile penetration with acceptable results. The reason for this is a combination of several factors, e.g. development of suitable material models for concrete, enhancement of numerical methodology and affordable high capacity computer systems. Furthermore, warhead penetration has primary been of interest for the armed forces and military industry, with a large part of the conducted research being classified during considerable time. The theoretical bases for concrete material behaviour and modelling with respect to FE analyses of projectile penetration are treated in the thesis. The development of weapons and fortifications are briefly discussed in the thesis. Warheads may be delivered onto a protective structure by several means, e.g. artillery, missiles or aerial bombing, and two typical warhead types were used within the study. These warhead types were artillery shells and unitary penetration bombs for the use against hardened targets, with penetration data for the later warhead type almost non-existing in the literature. The penetration of warheads in concrete protective structures was therefore studied through a combination of experimental work, empirical penetration modelling and FE analyses to enhance the understanding of the penetration phenomenon. The experimental data was used for evaluation of empirical equations for concrete penetration and FE analyses of concrete penetration, and the use of these methods to predict warhead penetration in protective structures are discussed within the thesis. The use of high performance concrete increased the penetration resistance of concrete targets, and the formation of front and back face craters were prevented with the use of heavily reinforced normal strength concrete (NSC) for the targets. In addition, the penetration depths were reduced in the heavily reinforced NSC. The evaluated existing empirical penetration models did not predict the behaviour of the model scaled hardened buried target penetrators in concrete structures with acceptable accuracy. One of the empirical penetration models was modified to better describe the performance of these penetrators in concrete protective structures. The FE analyses of NSC gave reasonable results for all simulation cases, with the best results obtained for normal impact conditions of the penetrators.<br>Analyser avseende stridsdelars penetration i skyddskonstruktioner av betong viktigt för studier av vapenverkan mot skyddskonstruktioner. Dessa analyser förutsätter att dimensionerande last i form av stridsdel bestäms, samt att dess karakteristik och verkan mot skyddskonstruktioner är kända. Konstitutiva modeller för betong utsatta för vapenverkan har varit av stort intresse under en lång tid och ett flertal materialmodeller har utvecklats. Det är emellertid först på senare år som det varit möjligt att använda finita element (FE) analyser for att simulera beteendet för betongmål vid projektilpenetration med acceptabla resultat. Anledningen till detta kan tillskrivas kombinationen av ett flertal faktorer, t ex utvecklingen av lämpliga materialmodeller, förbättringar av numerisk metodik och utvecklingen av kostnadseffektiva beräkningsdatorer. Penetration av stridsdelar har dessutom i huvudsak varit av intresse för militären och försvarsindustrin, vilket har resulterat i att en stor del av den bedrivna forskningen har varit hemligstämplad under lång tid. Grunderna avseende betongs materialbeteende och beskrivning av detta med avseende på FE-analyser av projektilpenetration behandlas i denna licentiatuppsats. Den fortifikatoriska utvecklingen och utvecklingen av vapen diskuteras kortfattad i uppsatsen. Ett flertal olika typer av stridsdelar är av intresse avseende verkan mot skyddskonstruktioner, t ex artillerigranater, missiler eller flygbomber. I denna studie beaktades två typiska stridsdelar, artillerigranater och penetrerande bomber. De senare är specifikt konstruerade för användande mot skyddskonstruktioner och företrädesvis mot betongkonstruktioner. Det visade sig dessutom att data avseende penetration i betong för denna typ av penetrerande stridsdelar i stort sett inte var publicerade. Penetration av stridsdelar i betong studerades därför med en kombination av experimentella metoder, empiriska penetrationsmodeller och FE-analyser för att öka förståelsen för problemställningen. De experimentella modellresultaten användes för att utvärdera både de empiriska penetrationsmodellerna och FE-analyserna avseende betongpenetration, med båda metodernas användande diskuterat i uppsatsen. Användandet av högpresterande betong ökade penetrationsmotståndet för betongmålen i jämförelse med standardbetongmålen. Det var även möjligt att förhindra kraterbildningen på fram- och baksidan av de kraftigt armerande standardbetongmålen, detta medförde även en reducerad penetration för projektilerna i målen. De existerande empiriska penetrationsmodellerna kunde inte förutsäga penetrationen av modellprojektilerna i betongmålen med godtagbara resultat. Istället vidareutvecklades en av dessa modeller för att bättre beskriva denna typ av penetrerande stridsdelar i skyddskonstruktioner av betong. Finita elementanalyserna av standardbetongmålen visade sig ge ett rimligt beteende för alla analyserade modeller, med de bästa resultaten erhållna för vinkelrätt anslag för de modellprojektilerna av de penetrerande stridsdelarna.<br>QC 20111116
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Jappie, Luqmaan. "Literature review of the use of common protective coatings for concrete structures with experiences in the South African context." Master's thesis, Faculty of Engineering and the Built Environment, 2019. http://hdl.handle.net/11427/30127.
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INTRODUCTION
The main objective of this dissertation is to compile a comprehensive literature review of surface protection systems, including their historical development, specification and use, and to conduct an industry review from the South African market. With a vast amount of deteriorating reinforced concrete structures and fast developing technology of surface treatments, it is important that engineers have a good working understanding of concrete deterioration, repair and the use of surface protection systems. Additionally, engineers need to have a good understanding of the pore structure of concrete and its transport properties as this is important to understanding the applicability and use of surface treatments (Breysse and Gérard, 1997; Leeming et al., 1997; Ballim, Alexander and Beushausen, 2009).
TRANSPORT PROPERTIES
The movement of ions or fluids in concrete occurs due to four basic mechanism; diffusion, permeation, absorption and migration, as briefly outlined below. The kinetics of movement is broadly governed by the size and nature of the concrete pore structure and its exposure environment (Ballim, Alexander and Beushausen, 2009; Basheer and Barbhuiya, 2010).
Process Description
Diffusion: Movement of ions, gas or liquid under a concentration gradient
Permeation: Movement of a fluid through a concrete matrix under an externally applied pressure gradient when saturated with that fluid
Absorption: Where a fluid is drawn into the pores of concrete through capillary suction
Migration: Movement of ions due to an electrical potential gradient Combined transport mechanisms and long-term changes in transport behaviour may need to be considered, Additionally, the size, nature and degree of cracking is an especially important consideration (Ballim, Alexander and Beushausen, 2009).
DETERIORATION OF CONCRETE
Rebar corrosion is the biggest threat to the durability of reinforced concrete structures, and is influenced mainly by the quality of the concrete, its cover depth to the reinforcement and the environmental exposure conditions. The primary causes of rebar corrosion are carbonation and chloride ingress. Chemical and acid attack may be of concern in certain environments. When using reactive aggregates, alkali-aggregate reaction may also be of concern to unreinforced and reinforced concrete. Surface protection systems can assist in reducing the effects due to the influence of the above penetration processes. Additionally,in harsh environmental conditions, such as in marine areas, additional protection measures are oftenrequired to ensure that concrete (existing or new) will not prematurely deteriorate during its service life (Beckett et al., 1987; Technical Committee 60-CSC RILEM, 1988; ACI Committee 201, 2008; Larsen, 2008; Ballim, Alexander and Beushausen, 2009; Gjørv, 2011). Typically, the following repair techniques may be considered in the repair and service life extension of concrete structures (Mackechnie and Alexander, 2001):
• Crack Repairs
• Patch Repairs
• Surface Coatings
• Migrating Corrosion Inhibitors (MCI’s)
• Electrochemical Techniques
• Cathodic Protection
• Demolition and Reconstruction
REPAIR STANDARDS
To ensure that a concrete repair project is successful, a systematic approach to the inspection and repair strategy development needs to be followed (Building Research Establishment, 2000b). The European standard EN 1504 and the Concrete Repair Manual from the American Concrete Institute provides such an approach. South Africa does not have such a standard, but is in the process of adopting the European standards for concrete (South African Bureau of Standards, 2017), EN 206 and EN 1992 - it would thus be highly beneficial for South Africa to move towards the adoption of the EN 1504 code as well. EN 1504-9 is a very important part of the code, as it provides a structured approach to the investigation of the cause of deterioration and outlines the “Principles of protection and repair.” EN 1504-2 covers the use of surface treatment systems, and its provisions are intended to be used as “Methods” in order to cover the “Principles” outlined in EN 1504-9 (Atkins et al., 2009; Raupach and Büttner, 2014).
SURFACE PROTECTION SYSTEMS
Modern technological advances have given rise to numerous surface treatment systems available on the market with various sub-categories that can assist in achieving the durability requirements of a concrete structure, from silanes, siloxanes, many types of polyurethanes and modified cementitious coatings as well as hybrid systems. Each product and system has its use, advantages and disadvantages and the selection of a system and decision on whether to apply a surface treatment or not can be a complicated matter. This decision is often left to the discretion of the engineer, and therefore engineers need to have a good working understanding of surface treatment systems (Leeming et al., 1997; Beushausen and Alexander, 2011; ACI Committee 546, 2014a). Surface protection systems can be classified according to the way in which the protective action is provided. This is the classification system used by EN 1504 and is divided as follows:
HYDROPHOBIC IMPREGNATION
These are low viscosity fluids which penetrate several millimetres into the concrete and considerably increase the water penetration resistance of concrete, whilst still allowing the passage of water vapour and gases. Typical examples are silanes and siloxanes. They are also referred to as pore lining penetrants (Beckett et al., 1987; Leeming et al., 1997; Bijen, 2003; ACI Committee 546, 2014b).
IMPREGNATION
These are low viscosity solutions that penetrate 1 - 3 mm into the concrete and effectively block pores. They differ from Hydrophobic Impregnations in that they are more restrictive to the passage of water vapour and gases. Typical examples are silicates and silicoflourides as well as certain types of polyurethanes (Beckett et al., 1987; Leeming et al., 1997).
COATINGS
These are treatments that form a continuous protective layer on the surface of the concrete. They are typically 0.1 mm - 5 mm thick, but may be thicker than 5 mm for certain applications. Typical examples are polymer-modified cementitious systems and polyurethanes (Beckett et al., 1987; BS EN 1504-2, 2004). Surface treatment systems need to meet specified performance criteria. In terms of the concrete durability, these are typically (Beckett et al., 1987):
• Ingress protection
• Moisture control
• Physical resistance / Surface improvement
• Resistance to chemicals
• Increasing resistivity
• Cathodic control
Treatment systems may also be required to bridge cracks, be applied to moist concrete or operate in harsh exposure and weather conditions. Therefore, the selection of a system needs to consider these factors and testing may be required for certain critical properties on-site to determine its suitability. Engineers, owners and suppliers need to collaborate in order to achieve a good solution. EN 1504-2 (2004) provides a detailed list of performance criteria for each of the various types of treatments along with the relevant code of practice for testing. In general, suppliers recommended application guidelines should be followed in the application of the system.
INDUSTRY REVIEW
A review of products and recent applications from Sika and A.B.E. Construction Chemicals is provided in this work. It was found that polymer-modified systems are still the most commonly used system. Siloxanes are often used for hydrophobic impregnation treatments, as the pure silanes are intended for high-performance usage and are only used in special circumstances. Each of the suppliers provides detailed application guidelines for each of their products as well as generalised expected performance criteria. Many of the products available have been formulated such that they are applicable to a wide range of applications, and it appears that some known problems with certain products have been improved on.
DISCUSSION & CONCLUSIONS
Findings of this report are listed below.
• The selection of a treatment system is a complex issue and therefore requires engineers to have a good appreciation of various surface treatments systems. A proper framework and set of guidelines is needed. Notwithstanding the above, collaboration between the owner, engineer and supplier will go a long way to a successful application.
• South Africa is lacking in the availability of detailed information for engineers to assess, design, specify and monitor treatment systems. South Africa is also in the process of adopting the Eurocodes for concrete design. The EN 1504 repair code contains specific provisions for surface treatments systems and should now be considered for implementation in South Africa. In the interim, EN 1504 can be used to assist in ensuring a standardised approach has been followed in a repair project.
• The current EN 1504 surface treatment classification divides systems into Hydrophobic Impregnation, Impregnation and Coatings. Whilst these are generally acceptable it may be worthwhile to reconsider Coatings as two types i.e. 'coatings’ for thinner coatings and 'overlays’ for thicker coatings, as these treatments may function in a very different manner - overlays function by their thickness providing protection and may not be especially complex treatments. They may also simply be applied for levelling and have a treatment or coating applied over them.
• Hydrophobic Impregnation is commonly achieved by the use of silanes or siloxanes or silanesiloxane blends. In particular, silane-siloxane blends are most commonly used. This is due to cost, difficulties in application of silanes, and environmental concerns with the volatile organic compound content of silanes.
• There are conflicting reports on the effectiveness in the use of silicate systems for improving concrete durability. This appears to be in-part due to the lack of agreement on the exact nature of the protection mechanism. Further research is required to reconcile differences in reporting.
• Polyurethanes are very versatile and are available in various forms. Many differences were found in literature on the effectiveness of polyurethanes for improving durability, and sometimes within the same generic type. One of the problems appears to be that researchers often don’t describe precisely enough the exact nature of the polyurethane that was used in their works. A standardised reporting approach is needed. However, polyurethanes have been shown to positively effect many durability issues in concrete such as water absorption, chloride diffusion and carbonation - depending on the specific polyurethane used.
• Polymer-modified cementitious coatings are the most commonly available and used surface treatments, and can be used for a wide range of applications. Their exact properties depend on their formulation, type of polymer and polymer-cement ratio. However, they are generally very versatile and most commercially available products can be used to achieve a wide range of properties, including improving the durability of existing concrete surfaces. They are sensitive to weather conditions during curing and special precautions may be required.
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Hassanein, Alea El Din Mohamed. "Intermittent cathodic protection of reinforced concrete structures." Thesis, Imperial College London, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.287182.
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Srour, Mahdi. "Rocking system for seismic protection of reinforced concrete structures." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amslaurea.unibo.it/3255/.
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Oleiwi, H. M. "Using cathodic protection to control corrosion of reinforced concrete structures." Thesis, University of Salford, 2018. http://usir.salford.ac.uk/47895/.
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Cathodic protection (CP) has been increasingly used on reinforced concrete structures to protect steel reinforcement from corrosion. However, due to the complexity of environmental conditions, the specifications in national and international standards are still open to discussion in engineering practices for their accurate suitability. To some extent, the design aspects are still based on practical experience. It implies a great deal of estimations and assumptions. The research conducted in the thesis aims to address some of these challenges. To obtain reliable experimental results, the present study at first investigated the influence of experimental methods on the measurement of concrete electrical resistivity. It studied the effect of alternative current (AC) frequency, electrode materials and electrode configuration. Based on the results, an optimised method was decided for all the series of the experimental tests in this study. The CP study consists of two major works. The first one was to investigate the chloride contaminated concrete exposed to atmospheric condition. Impressed constant current method was adopted for the operation of CP. A series of electrical and electrochemical measurements were conducted for concrete resistivity, corrosion potential, corrosion rate, degree of polarization, instant-off potential and four-hour potential decay. An evaluation on the current adopted criterion in standards has been carried out on the experimental results. The second work was to investigate the corrosion of rebar in concrete specimens submerged (fully and partially) in salty water. For such more corrosive environment, a comparison between the impressed CP operation using constant current and that using constant potential has been conducted. The experiments evaluated the effects of the two major environmental factors, i.e. water and chloride contents, on reinforced concrete durability. The work provided a deep understanding on the electrochemical behaviour of the reinforced concrete system and effectiveness of CP implementation under severe conditions. The research work has an important contribution to fundamental science of corrosion and reinforced concrete deterioration, and the technology and practical application of CP for reinforced concrete structures. The main results of this work indicate the important influence of the frequency and electrode configuration on the electrical resistance measurement. For the reliability of electrical resistivity measurement, a high frequency of 10,000 Hz and an internal carbon fibre electrode method are recommended. Regarding the CP for the chloride contaminated reinforced concrete exposed to the atmosphere, it is suggested that adopting an instant-off potential of -500 mV with respect to Ag/AgCl/0.5KCl reference electrode can provide sufficient protection for the reinforced concrete of up to 0.59 % total chloride by weight of concrete, or concrete resistivity is greater than 6.7 kΩ.cm. Furthermore, it was found that the 100 mV depolarization criterion for the evaluation of CP performance gives an overestimated protection. A depolarization of 50 mV is therefore proposed. In terms of the submerged specimens, the results showed that the water content and chloride content should be explicitly related to the corrosion state rather than through a single parameter of the concrete resistivity for the complicated situations because the water content will affect the oxygen transportation in concrete, and the oxygen availability at the rebar surface will play an important role in the corrosion process, and this is unassessable by concrete resistivity. Moreover, 4 or 24 hours for the 100 mV depolarisation criterion in standards is not applicable for CP assessment where concrete structures are fully submerged due to the low availability of oxygen. On the other hand, the depolarization criterion can be used if the specimens are partially submerged, but different parameters affect the depolarization value such as the magnitude of the applied protection current or potential, chloride concentration, oxygen availability and time of depolarization.
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Selander, Anders. "Hydrophobic Impregnation of Concrete Structures : Effects on Concrete Properties." Doctoral thesis, KTH, Brobyggnad inkl stålbyggnad, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-12179.
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Hydrophobic impregnations often referred to as water repellent agents, today mainly consisting of alkylalkoxysilanes, are often used on concrete to prolong the service life of the structure. This is accomplished by protecting the reinforcement bars from chlorides or by changing the moisture content inside. When the concrete is treated with a water repellent agent the properties of the surface layer becomes hydrophobic and thereby water droplets are stopped from entering, still allowing water vapour to pass through. This change can reduce chloride ingress and stop heavy rain from penetrating through the surface layer. This thesis presents results concerning how the properties of concrete are affected by a hydrophobic impregnation. Moisture transport and fixation in the surface layer of the concrete are studied as well as the secondary effects of more practical use such as the effect on chloride ingress, water absorption and humidity level. It also presents results on how the penetration depth and concentration of the water repellent agent (i) depend on a number of parameters, and (ii) affect the outcome of the treatment. Water repellent treatments on a number of different concrete structures in Stockholm, ranging from tunnel to high-rice building, are evaluated as well. The three most important factors for the penetration of any water repellent agent into concrete are time, porosity and degree of saturation. A semi-empirical equation is derived that gives an idea on how much these factors affect the efficient penetration depth of the water repellent agent. The depth and concentration have a major effect on the performance of the treatment. The moisture diffusion coefficient for a water repellent treated concrete is close to constant and not nearly as dependent on the relative humidity (RH) as for untreated concrete. Unlike untreated concrete, where capillary suction plays an important role for the moisture transport at high RH, the vapour transport is the dominant transport mechanism even at high RH for water repellent treated concrete. The moisture fixation is affected by a water repellent treatment and the effect is clearest at high moisture levels. The main reason for this is that the capillary porosity is affected by the treatment to a relatively high degree while the gel porosity to a large extent remains unaffected. A hypothesis is presented which suggests that the RH inside the concrete at the time of the treatment affects not only the depth and concentration but also in which range of pore radii the water repellent agent is present and active. The durability of hydrophobic impregnations can be divided into surface effects and in depth effects. The first is sensitive to the environmental and mechanical loadings and normally disappears within a year while the later can be long lasting if a sufficient depth is reached. Hydrophobic impregnations are not the answer to all problems in concrete related to moisture, but if correctly used it can prolong the service life of the structure which will lead to savings of natural resources and thus both economical and environmental savings for the community.<br>Vattenavvisande impregneringsmedel, som i dagsläget till största del består av alkylalkoxysilaner, används ofta på betong för att förlänga livslängden på konstruktionen. Detta syfte uppnås genom att armeringen skyddas mot klorider eller att fukthalten inuti betongen sänks. När betongen impregneras ändras ytskiktets fuktmekaniska egenskaper från hydrofila till hydrofoba vilket gör att vattendroppar kan stoppas medan vattenånga tillåts passera. Dessa förändrade egenskaper kan medföra att kloridinträngningen minskar och att kraftiga regn inte tränger genom det impregnerade skiktet. Denna avhandling presenterar resultat om hur betongen påverkas av en vattenavvisande impregnering. Fukttransport och fuktfixering i betongens ytskikt har undersökts men även sekundära effekter som kloridinträngning, vattenabsorption och förändring i fuktinnehåll vilka alla är av större praktisk nytta. Avhandlingen presenterar också resultat om vilka faktorer som påverkar impregneringens inträngningsdjup och koncentration samt vilken betydelse dessa har för funktionen. För att utvärdera impregneringars effekt i olika miljöer har ett stort antal objekt i Stockholm undersökts, innefattande olika konstruktioner från en tunnel till höghus. Impregneringens inträngningsdjup och koncentration har en avgörande betydelse för dess funktion. De tre viktigaste faktorerna för alla impregneringsmedels inträngning i betong är tid, porositet och fuktnivå. En semiempirisk ekvation har tagits fram där det framgår hur dessa tre faktorer påverkar det slutliga inträngningsdjupet för impregneringen. Till skillnad från obehandlad betong är transportkoefficienten för en impregnerad betong nästan oberoende av den relativa fuktigheten (RF) i omgivningen. Vid höga RF, där största delen av fukttransporten i obehandlad betong sker på grund av kapillärkrafter, är ångtransporten fortfarande den dominerande transportmekanismen i impregnerad betong. Fuktfixeringen i betong påverkas av en impregnering och effekten är störst vid höga RF. Det är dock tydligt att en viss mängd fukt finns inuti den impregnerade betongen. Detta kan förklaras med att största delen av kapillärporerna påverkas av impregneringen medan gelporerna förblir obehandlade. Resultaten indikerar också att fuktnivån vid impregneringstillfället avgör vilken del av porsystemet som kan behandlas och inte bara koncentrationen och inträngningsdjupet. Långtidsegenskaperna hos impregneringen kan delas upp i yt- och djupeffekt. Effekten på ytan avtar normalt sett inom ett år på grund av damm och partiklar, UV-ljus, slitage mm. Djupeffekten påverkas däremot inte av dessa faktorer och kan finnas kvar i decennier. Vattenavvisande impregneringar är inte lösningen på alla fuktrelaterade problem i betong, men om de används på rätt sätt så kan det förlänga livslängden på många konstruktioner. Detta leder till ett bättre hushållande med naturresurser och därmed både ekonomiska och miljömässiga besparingar för samhället.<br>QC20100715
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Walsh, Michael Thomas. "Corrosion of Steel in Submerged Concrete Structures." Scholar Commons, 2015. http://scholarcommons.usf.edu/etd/6048.
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This investigation determined that severe corrosion of steel can occur in the submerged portions of reinforced concrete structures in marine environments. Field studies of decommissioned pilings from actual bridges revealed multiple instances of strong corrosion localization, showing appreciable local loss of steel cross-section. Quantitative understanding of the phenomenon and its causes was developed and articulated in the form of a predictive model. The predictive model output was consistent with both the corrosion rate estimates and the extent of corrosion localization observed in the field observations. The most likely explanation for the observed phenomena that emerged from the understanding and modeling is that cathodic reaction rates under oxygen diffusional limitation that are negligible in cases of uniform corrosion can nevertheless support substantial corrosion rates if the corrosion becomes localized. A dynamic evolution form of the model was created based on the proposition that much of the steel in the submerged concrete zone remained in the passive condition given cathodic prevention that resulted from favorable macrocell coupling with regions of the steel that had experienced corrosion first. The model output also matched observations from the field, supporting the plausibility of the proposed scenario.
The modeling also projected that corrosion in the submerged zone could be virtually eliminated via the use of sacrificial anode cathodic protection; the rate of corrosion damage progression in the low elevation zone above water could also be significantly reduced. Continuation work should be conducted to define an alternative to the prevalent limit-state i.e., visible external cracks and spalls, for submerged reinforced concrete structures. Work should also be conducted to determine the possible structural consequences of this form of corrosion and to assess the technical feasibility and cost/benefit aspects of incorporating protective anodes in new pile construction.
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Christodoulou, Christian. "Repair and corrosion management of reinforced concrete structures." Thesis, Loughborough University, 2013. https://dspace.lboro.ac.uk/2134/13577.
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The durability of concrete structures is affected by a number of factors such as environmental exposure, electrochemical reactions, mechanical loading, impact damage and others. Of all of these, corrosion of the reinforcement is probably the main cause for the deterioration of steel reinforced concrete (RC) structures. Corrosion management is becoming increasingly necessary as a result of the growing number of ageing infrastructure assets (e.g. bridges, tunnels etc.) and the increased requirement for unplanned maintenance in order to keep these structures operational throughout their design life (and commonly, beyond). The main RC repair, refurbishment and rehabilitation approaches generally employed can be broadly categorised under a) conventional, b) surface treatments, c) electrochemical treatments and d) design solutions. The overarching aim of this research was to identify the key corrosion management techniques and undertake empirical investigations focused on full-scale RC structures to investigate their long-term performance. To achieve this, individual research packages were identified from the above broad five approaches for repair, replacement and rehabilitation. These were 1) Patch repairs and incipient anodes, 2) Impressed Current Cathodic Protection, 3) Galvanic Cathodic Protection and 4) Hydrophobic treatments. The selection of the above research packages was based on past and present use by the construction industry to repair, refurbish and rehabilitate RC structures. Their contributions may be broadly categorised as i) Investigations on how specific treatments and materials perform, ii) Investigations on the effectiveness of existing methods of measurements and developing alternatives, iii) Changes to the existing theory of corrosion initiation and arrest and iv) Changes to management framework strategies. The key findings from each research package can be summarised as follows: Macrocell activity appears to be a consequence rather than a cause of incipient anode formation in repaired concrete structures, as has previously been presented; ICCP has persistent protective effects even after interruption of the protective current; Discrete galvanic anodes installed in the parent concrete surrounding the patch repair are a feasible alternative to galvanic anodes embedded within the patch repairs of RC structures; Silanes may have a residual hydrophobic effect even after 20 years of service.
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Sohrabi, Mohammad Reza. "Thin layered systems for the repair and protection of concrete structures." Thesis, University of Newcastle Upon Tyne, 1996. http://hdl.handle.net/10443/485.
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Thin layered systems can be considered as a solution to the repair and protection of concrete structures. This subject was studied in the current investigation. Some common uses of these systems include protection, upgrading and rehabilitation of the floor slabs,restoration of appearance of the structures, impermeability, skid resistance, wear resistance, and protection of the reinforcing steel of concrete structures against atmospheric or chemical attack. However it can be said that protection, upgrading and rehabilitation of floor slabs are the main uses for the design of modem thin layered systems. For example a thin layer of a polymer concrete with a thickness of less than 3 nun can resist a very highly concentrated load resulting from a steel wheel rolling load of 5000 N without any sign of defect. Thin layer systems therefore include traditional screeds, externally bonded steel plates, plasters and coatings as well as the more recent hi - tech. systems. Like any other structure, a thin layered system may break down as the result of many causes. Among other types of failures, delamination defect is the most common mode of failure and particularly relevant to a thin layered system. This phenomenon which mostly occur between the upper layer directly subjectedto the load and the subsequent layer, is due to debonding or slippage at the interface of the two layers. A delamination may occur at the interface of a thin layered system even without any sign of failure in other parts of the structure. Steel wheeled trolleys and fork - lift trucks are among the most anticipated types of loading and causes of failures in the thin layered systems. Different combinations of thin layered systems were prepared using some special flooring materials, both in small and large scales. Despite the lack of any standard test, the action of a steel wheel rolling load on the ready made and purpose made specimens of thin layered systems was well simulated using the Steel Wheel Rolling Load Rig. The NUROLF, Newcastle University Rolling Load Facility, was also used for simulating the action of a tyred vehicle wheel rolling load on the thin layered systems of large scale. Some simple ways for detecting any possible delamination at the interface of the thin layered systems were examined. In addition to the available material characteristics tests, a relatively new simple shear box test was proposed for defming the relationship between normal stress and the correspondings hear strength for each combination of the materials at each age of the test. The results were then used as the basis for the subsequent structural analysis. The structural analysis of the systems was carried out for both of the experiments using the finite element method and the interface technique. In spite of the simplifications made in the solution, the analytical results were consistent with the experimental results to a considerable extent. Based on the results of this investigation, a relatively constitutive procedure was concluded for predicting the behaviour of a thin layered system under the action of a wheel rolling load with regard to the delamination defect.
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Cassidy, Eric Dana. "Development and Structural Testing of FRP Reinforced OSB Panels for Disaster Resistant Construction." Fogler Library, University of Maine, 2002. http://www.library.umaine.edu/theses/pdf/CassidyED2002.pdf.
Full textBooks on the topic "Protective Concrete Structures"
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Chess, Paul M. Cathodic Protection for Reinforced Concrete Structures. CRC Press, 2018. http://dx.doi.org/10.1201/9781351045834.
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Woodson, R. Dodge. Concrete structures: Protection, repair and rehabilitation. Butterworth-Heinemann, 2009.
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1938-, Mailvaganam N. P., ed. Repair and protection of concrete structures. CRC Press, 1992.
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Perkins, Philip H. Repair, protection and waterproofing of concrete structures. 3rd ed. E. & F.N. Spon, 1997.
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Henderson, J. The repair and protection of concrete structures. Concrete Construction Exhibitions, 1988.
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Perkins, Philip Harold. Repair, protection and waterproofing of concrete structures. 3rd ed. E&FN Spon, 1997.
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Harold, Perkins Philip, ed. Repair, protection, and waterproofing of concrete structures. Elsevier Applied Science Publishers, 1986.
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précontrainte, Fédérationinternationale de la, and Structural Engineers Trading Organisation, eds. Corrosion protection of prestressing steels. SETO, 1996.
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National Association of Corrosion Engineers. Cathodic protection of reinforcing steel in atmospherically exposed concrete structures. National Association of Corrosion Engineers, 1990.
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Sohanghpurwala, Ali Akbar. Long-term effectiveness of cathodic protection systems on highway structures. U.S. Dept. of Transportation, Federal Highway Administration, Turner-Fairbank Highway Research Center (6300 Georgetown Pike, McLean, 22101-2296), 2003.
Find full textBook chapters on the topic "Protective Concrete Structures"
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Han, Lin-Hai. "Protective Design of Concrete-Filled Steel Tubular (CFST) Structures." In Theory of Concrete-Filled Steel Tubular Structures. Springer Nature Singapore, 2023. http://dx.doi.org/10.1007/978-981-99-2170-6_7.
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Hu, Zongbo. "Analysis of Impact Resistance and Optimization of Protective Capacity for Steel Reinforced Concrete Columns." In Lecture Notes in Civil Engineering. Springer Nature Singapore, 2024. https://doi.org/10.1007/978-981-97-6238-5_14.
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AbstractThrough simulated horizontal impact tests on steel-reinforced concrete column components, the dynamic response of steel-reinforced concrete columns under different impact heights, boundary conditions, and impact velocities was obtained. The results indicate that with an increase in impact energy, the peak impact force shows an upward trend. As the impact height increases, the impact force gradually decreases, with higher forces near the end. When the mass of the impacting object is 2580 kg and the minimum velocity is 4.58 m/s, the maximum residual displacement occurs in the impact zone. Based on the simulated test results, the impact failure modes of steel-reinforced concrete columns can be classified as slight damage, moderate damage, severe damage, and critical damage. A model reflecting the changes in mechanical characteristics of steel-reinforced concrete column structures was established based on the damage states and impact resistance mechanisms at each loading stage of the column components. Active and passive protective structures were proposed.
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Arowojolu, Olaniyi, Ahmed Ibrahim, and Mahmoud Reda Taha. "Parametric Study on the Performance of UHPC and Nano-modified Polymer Concrete (NMPC) Composite Wall Panels for Protective Structures." In International Congress on Polymers in Concrete (ICPIC 2018). Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-78175-4_87.
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Radonjanin, Vlastimir, Mirjana Malešev, Ivan Lukić, Slobodan Šupić, Mirjana Laban, and Olivera Bukvić. "Possible Utilization of Used Precast Building Elements Through Consideration of Concrete Carbonation Degree." In Lecture Notes in Civil Engineering. Springer Nature Switzerland, 2024. http://dx.doi.org/10.1007/978-3-031-57800-7_49.
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AbstractSignificant changes in the strategic goals of the construction sector at the global level have been visible in recent years. By implementing the fundamental principles of sustainable development and circular economy, the modern construction industry tries to contribute to a healthier environment by reducing CO2 emissions, minimizing waste landfills, and preserving non-renewable natural resources. The possibilities of reusing prefabricated concrete elements of existing buildings instead of their traditional recycling on a material level or disposing of them in landfills are analyzed in this paper. Special attention in the research was placed on the carbonation of prefabricated reinforced concrete elements of buildings, as it is one of the most frequent processes that accelerate the deterioration of RC structures. Long-term carbonation processes inevitably result in reinforcement corrosion and accompanying damage to the concrete cover, therefore some constrains for the further use of prefabricated RC building elements must be precisely defined. In this study, the potential use of prefab RC building elements was determined by calculating the depth of carbonation while taking into account the age of buildings and environmental conditions (relative air humidity, position of prefab element). Depending on the thickness of the carbonized concrete and the type and intensity of damage to the reinforcement and concrete, various variants for further use of the dismantled prefabricated RC building elements were proposed (reuse without restrictions, use in the interior of new buildings, use in less demanding facilities, reuse after application of a protective coating, replacement of the protective cover and reuse etc.).
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Chernobryvko, Maryna, Viktor Vasechko, Igor Marshuba, and Svitlana Svetlichna. "Dynamic Strength of Protective Structures from Hybrid Fiber Reinforced Concrete Under High Compressive Strain Rates." In Smart Technologies in Urban Engineering. Springer Nature Switzerland, 2023. http://dx.doi.org/10.1007/978-3-031-46877-3_41.
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El-Reedy, Mohamed Abdallah. "Methods for Protecting Steel Reinforcements." In Steel-Reinforced Concrete Structures, 3rd ed. CRC Press, 2023. http://dx.doi.org/10.1201/9781003407058-7.
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Chess, Paul M. "The Corrosion Process in Reinforced Concrete." In Cathodic Protection for Reinforced Concrete Structures. CRC Press, 2018. http://dx.doi.org/10.1201/9781351045834-1.
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Chess, Paul M. "History of Cathodic Protection in Reinforced Concrete." In Cathodic Protection for Reinforced Concrete Structures. CRC Press, 2018. http://dx.doi.org/10.1201/9781351045834-2.
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Chess, Paul M. "Present Use of Impressed Current Cathodic Protection in Reinforced Concrete." In Cathodic Protection for Reinforced Concrete Structures. CRC Press, 2018. http://dx.doi.org/10.1201/9781351045834-3.
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Chess, Paul M. "Present Use of Galvanic Anodes for Cathodic Protection in Reinforced Concrete." In Cathodic Protection for Reinforced Concrete Structures. CRC Press, 2018. http://dx.doi.org/10.1201/9781351045834-4.
Full textConference papers on the topic "Protective Concrete Structures"
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Bavarian, Behzad, Akinbosede Oluwaseye, Lisa Reiner, and Jessica Meyer. "Migrating Corrosion Inhibitors to Protect Reinforced Concrete Structures." In CORROSION 2018. NACE International, 2018. https://doi.org/10.5006/c2018-11011.
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Abstract Most transportation infrastructure is built from steel and concrete. The steel may be in structural sections, such as girders, piles or rails, or embedded in concrete to form reinforced or prestressed concrete. Concrete provides excellent protection for embedded steel because Portland cement is very alkaline, forming a passive, protective layer on the steel surface. Concrete is also permeable, and even good-quality concrete can be penetrated by aggressive chemical ions that may initiate steel corrosion. Migrating corrosion inhibitors (MCIs), a blend of amine carboxylates and amino alcohols, show versatility as admixtures, surface treatments (coatings) and in rehabilitation programs. Examination of the embedded steel rebar after corrosion tests showed no corrosion attack for the MCI treated concrete samples, while non-treated concrete showed localized corrosion. X-ray photoelectron spectroscopy and depth profiling confirmed that the inhibitor had reached the rebar surface in about 150 days. The amine-rich compound on the rebar surface improved corrosion protection for the MCI treated steel rebar even in the presence of chloride ions and prevented red rust formation.
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Cheshire, Brian, and Vaughn O‘Dea. "Concrete Structures in Wastewater Environments: Key Considerations for Substrate Repair and Surface Preparation for Protective Coatings/Linings Applications." In CORROSION 2024. AMPP, 2024. https://doi.org/10.5006/c2024-20364.
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Abstract Concrete is the most predominately used construction material for wastewater collection and treatment facilities. Nevertheless, there are still many questions and misconceptions on how to properly evaluate this substrate prior to commencing a coating or lining project. Knowing how to address any defects or necessary repairs is imperative for all projects, but in many cases, some of these repairs or details are omitted. In turn, questions still arise from the field on how to properly prepare these surfaces. Answering these questions is a vital task, as surface preparation is a major component in the successful installation of protective linings or polymer concretes. The main goal for any concrete coating project is the long-term protection of the substrate from corrosive and physical forces, which cannot be achieved without all these key steps taking place prior to placing the asset into immersion or chemical containment service. In summary, this paper will review the common forms of concrete attack mechanisms that occur in wastewater environments and will also review current industry best practices to repair (and prepare) concrete prior to the application of polymer concretes or high-performance protective linings. Some select case histories will be discussed in order to illustrate some of the concepts covered throughout the paper.
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O’Dea, Vaughn, Tim Fitzgerald, and Michael Lovell. "Coating Concrete with High-Performance Protective Linings: Understanding Mechanisms of Outgassing-induced Film Defects." In CONFERENCE 2025. AMPP, 2025. https://doi.org/10.5006/c2025-00089.
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Abstract Ordinary portland cement concrete is the most predominately used construction material for the building of chemical containment and immersion service structures in the municipal water and wastewater treatment industry. Protecting concrete with high-performance protective linings is crucial for preventing the deterioration of water and wastewater treatment structures from chemical attack, chloride ingress, and carbonation. The application of high-performance protective linings to hardened concrete—which includes shotcrete and cementitious repair mortars—can be a challenge due to its inherently porous structure full of tiny capillaries and air pockets, as well as bugholes when casted. Concrete outgassing is the release of air and vapor pressure from these pores and can lead to defects such as craters, bubbles, and pinholes in the wet film of a protective lining. This adverse phenomenon is typically caused by a temperature change within or near the concrete surface during application of the protective lining. Rising temperatures cause air and water vapor to expand and emit from concrete passing through the wet lining before it cures, ultimately leading to film defects. This paper will describe the mechanisms causing concrete outgassing and explore effective application methods to mitigate its impact on high-performance linings when applied to concrete and other cementitious substrates.
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Fuentes, L., S. Verhulst, J. O. Jirsa, D. W. Fowler, H. G. Wheat, and T. Moon. "The Use of Composite Wrapping on Reinforced Concrete Structures." In CORROSION 2000. NACE International, 2000. https://doi.org/10.5006/c2000-00820.
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Abstract The use of composite laminates as protective barriers on concrete surfaces has increased over the past few years. One of the recent applications is in the rehabilitation of concrete structures which have suffered corrosion damage. An actual system has recently been installed in Texas. A laboratory test program has been developed to simulate components of that system. Some of the variables being studied include specimen shape, flexural cracks, repair materials, length of wrap, resin selection, and concrete surface condition. Some of the features of the laboratory test program will be described.
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Kessler, R. J., and R. G. Powers. "Update on Cathodic Protection of Reinforcing Steel in Concrete Marine Substructures." In CORROSION 1993. NACE International, 1993. https://doi.org/10.5006/c1993-93326.
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Abstract Corrosion of steel reinforcing bars in concrete due to the intrusion of chloride ions from seawater affects many structures in the marine environment. In recent years, cathodic protection has emerged as a practical means of minimizing the rate of corrosion in these structures. In Florida a variety of cathodic protection systems have been installed and evaluated for their ability to deliver the required protective current and for their durability. This paper describes three types of impressed current systems that are in operation on marine bridge substructures in Florida.
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Prabhu-Gaonkar, G. V., and Madan Kamat. "Developments and Application of Volatile Inhibitor Additives in Mortar for Repair of Concrete Structures." In CORROSION 2003. NACE International, 2003. https://doi.org/10.5006/c2003-03369.
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Abstract Repairs and rehabilitation of concrete structures is one of the most challenging job engineering fraternity faces today all over the world. Corrosion of reinforcing steel has been identified as the single largest factor responsible for deterioration of reinforced concrete structures. Effective procedures employed in the past to combat reinforcement corrosion have required either extensive cutting out and replacement of contaminated concrete at the level of embedded steel and treating the same with conventional protective measures or the use of electrochemical measures such as cathodic protection. Alternatively corrosion inhibitors either contact or volatile type have been used over the past decade. This paper presents the experimental work carried out to identify effective volatile corrosion inhibitors as an admixture in repair mortar adopting to Indian tropical conditions.
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Ard, Chris. "Application of Fluid Applied Linings in Concrete Secondary Containment Structures." In Paint and Coatings Expo (PACE) 2008. SSPC, 2008. https://doi.org/10.5006/s2008-00002.
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Current governmental regulations have mandated that a high number of concrete structures, serving as secondary containment for chemical storage areas, are to receive some type of protective lining. These linings serve two purposes: 1) They protect the concrete substrate from chemical attack and physical abuse, and 2) They help to retain chemicals that leak from their primary containment or are spilt during transfer, preventing them from leaching through cracks or joints in the concrete and into the ground soil below. These linings can be pre-fabricated liners or fluid applied polymeric coatings and linings installed on-site.
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Najar, Manuel. "Determining When to Coat Concrete." In Coatings+ 2020. SSPC, 2020. https://doi.org/10.5006/s2020-00042.
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Abstract Reinforced concrete is the most common building material in water and wastewater treatment facilities. It is very common to see unprotected concrete in severely corrosive environments or corroding reinforcing steel that has been exposed due to construction defects or coating failures. The decision to coat new and existing concrete structures can be very difficult for owners due to the cost, turn-around times for putting structures back into service, and lack of confidence in certain protective coatings. This paper will review some of the service environments and data that can prompt an owner to protect their structures with coatings and linings.
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Najar, Manuel. "Determining When to Coat Concrete." In Coatings+ 2020. SSPC, 2020. https://doi.org/10.5006/s2020-00033.
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Abstract Reinforced concrete is the most common building material in water and wastewater treatment facilities. It is very common to see unprotected concrete in severely corrosive environments or corroding reinforcing steel that has been exposed due to construction defects or coating failures. The decision to coat new and existing concrete structures can be very difficult for owners due to the cost, turn-around times for putting structures back into service, and lack of confidence in certain protective coatings. This paper will review some of the service environments and data that can prompt an owner to protect their structures with coatings and linings.
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Canto, Jorge, Edgar Maya, Lorenzo M. Martinez-dela-Escalera, et al. "Engineering the Rehabilitation of Reinforced Concrete Structures in Gas and Fuel Oil Distribution Docks of the Pacific Coast of Mexico." In CORROSION 2010. NACE International, 2010. https://doi.org/10.5006/c2010-10120.
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Abstract This work serves to report on the results of the corrosion evaluations produced by Mexico´s State owned Company initiative to rehabilitate the reinforced concrete structures in their facilities that are used to supply gas and fuel oil to important coastal regions of Mexico including Mazatlan and Salina Cruz. A general assessment is presented showing the concrete repair needs and corrosion prevention requirements for the steel reinforcement in concrete beams, slabs and piles of these structures. A diagnosis was performed employing different test methods including visual survey, sonic hammering, sclerometer concrete strength measurements, corrosion potential measurement, concrete electrical conductivity, and chloride penetration. The results of the study are discussed, as well as the recommendations in terms of repairs to be performed and protection to be used. The general recommendation delivered was to mitigate corrosion activity through cathodic protection for the reinforcing steel and protective coatings. The cathodic protection recommended was mainly embedded distributed and discrete sacrificial anodes.
Reports on the topic "Protective Concrete Structures"
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Scott, Dylan, Steven Graham, Bradford Songer, Brian Green, Michael Grotke, and Tony Brogdon. Laboratory characterization of Cor-Tuf Baseline and UHPC-S. Engineer Research and Development Center (U.S.), 2021. http://dx.doi.org/10.21079/11681/40121.
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This experimental effort is part of a larger program entitled Development of Ultra-High-Performance Concrete Tools and Design Guidelines. This program operates in accordance with an agreement concerning combating terrorism research and development between the United States of America Department of Defense and the Republic of Singapore Ministry of Defence. The objective of the program is to develop a better understanding of the potential benefits that may be achieved from the application of ultra-high-performance concrete (UHPC) materials for protective structures. The specific effort detailed in this report will provide insight into laboratory-scale mechanical properties of Cor-Tuf and a proprietary material termed UHPC-Singapore (UHPC-S).
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Sparks, Paul, Jesse Sherburn, William Heard, and Brett Williams. Penetration modeling of ultra‐high performance concrete using multiscale meshfree methods. Engineer Research and Development Center (U.S.), 2021. http://dx.doi.org/10.21079/11681/41963.
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Terminal ballistics of concrete is of extreme importance to the military and civil communities. Over the past few decades, ultra‐high performance concrete (UHPC) has been developed for various applications in the design of protective structures because UHPC has an enhanced ballistic resistance over conventional strength concrete. Developing predictive numerical models of UHPC subjected to penetration is critical in understanding the material's enhanced performance. This study employs the advanced fundamental concrete (AFC) model, and it runs inside the reproducing kernel particle method (RKPM)‐based code known as the nonlinear meshfree analysis program (NMAP). NMAP is advantageous for modeling impact and penetration problems that exhibit extreme deformation and material fragmentation. A comprehensive experimental study was conducted to characterize the UHPC. The investigation consisted of fracture toughness testing, the utilization of nondestructive microcomputed tomography analysis, and projectile penetration shots on the UHPC targets. To improve the accuracy of the model, a new scaled damage evolution law (SDEL) is employed within the microcrack informed damage model. During the homogenized macroscopic calculation, the corresponding microscopic cell needs to be dimensionally equivalent to the mesh dimension when the partial differential equation becomes ill posed and strain softening ensues. Results of numerical investigations will be compared with results of penetration experiments.
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Myrttinen, Henri. Connecting the Dots: Arms Control, Disarmament and the Women Peace and Security Agenda. UNIDIR, 2020. http://dx.doi.org/10.37559/gen/20/01.
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Connecting the Dots examines the normative and practical overlaps and connections of the Women, Peace and Security (WPS) agenda with the field of arms control and disarmament. Using an original approach to gender-responsive arms control and disarmament measures that is structured around the four WPS pillars of participation, prevention, protection, and relief and recovery, this report identifies current best practices and areas for further action. The report shows that further integration can bring benefits for both fields. For the arms control and disarmament community, the WPS pillars give structure and guidance to the comprehensive integration of gender perspectives, which thus far has been a piecemeal effort. For WPS policy actors and practitioners, engaging with arms control and disarmament helps to operationalize the WPS agenda, giving concrete substance to each of its pillars.
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Elimam, Sarah. Canada's economic integration and resilience: lessons from CIRANO research. CIRANO, 2025. https://doi.org/10.54932/xusv8629.
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Despite the historically close relations that have enabled Canada and the United States to benefit from their trade integration, recent disruptions to world trade have challenged the foundations of this so-called protective interdependence. Since 2020, a number of research projects conducted at CIRANO have highlighted the structural vulnerabilities generated by this interdependence: saturation of logistics infrastructures, asymmetric exposure to shocks, overdependence on a single partner. All these factors call for a rethinking of our economic strategies and a reassessment of our investment priorities. These long-identified vulnerabilities now require concrete, targeted and coordinated responses.
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Groeneveld, Andrew, and C. Crane. Advanced cementitious materials for blast protection. Engineer Research and Development Center (U.S.), 2023. http://dx.doi.org/10.21079/11681/46893.
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Advanced cementitious materials, commonly referred to as ultra-high performance concretes (UHPCs), are developing rapidly and show promise for civil infrastructure and protective construction applications. Structures exposed to blasts experience strain rates on the order of 102 s-1 or more. While a great deal of research has been published on the durability and the static properties of UHPC, there is less information on its dynamic properties. The purpose of this report is to (1) compile existing dynamic property data—including compressive strength, tensile strength, elastic modulus, and energy absorption—for six proprietary and research UHPCs and (2) implement a single-degree-of-freedom (SDOF) model for axisymmetric UHPC panels under blast loading as a means of comparing the UHPCs. Although simplified, the model allows identification of key material properties and promising materials for physical testing. Model results indicate that tensile strength has the greatest effect on panel deflection, with unit weight and elastic modulus having a moderate effect. CEMTECmultiscale® deflected least in the simulation. Lafarge Ductal®, a commonly available UHPC in North America, performed in the middle of the five UHPCs considered.
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ALLAN, M. L. EVALUATION OF COATINGS AND MORTARS FOR PROTECTION OF CONCRETE COOLING TOWER STRUCTURES FROM MICROBIOLOGICALLY INFLUENCED CORROSION IN GEOTHERMAL POWER PLANTS. Office of Scientific and Technical Information (OSTI), 1999. http://dx.doi.org/10.2172/751115.
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Wu, Yingjie, Selim Gunay, and Khalid Mosalam. Hybrid Simulations for the Seismic Evaluation of Resilient Highway Bridge Systems. Pacific Earthquake Engineering Research Center, University of California, Berkeley, CA, 2020. http://dx.doi.org/10.55461/ytgv8834.
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Bridges often serve as key links in local and national transportation networks. Bridge closures can result in severe costs, not only in the form of repair or replacement, but also in the form of economic losses related to medium- and long-term interruption of businesses and disruption to surrounding communities. In addition, continuous functionality of bridges is very important after any seismic event for emergency response and recovery purposes. Considering the importance of these structures, the associated structural design philosophy is shifting from collapse prevention to maintaining functionality in the aftermath of moderate to strong earthquakes, referred to as “resiliency” in earthquake engineering research. Moreover, the associated construction philosophy is being modernized with the utilization of accelerated bridge construction (ABC) techniques, which strive to reduce the impact of construction on traffic, society, economy and on-site safety. This report presents two bridge systems that target the aforementioned issues. A study that combined numerical and experimental research was undertaken to characterize the seismic performance of these bridge systems. The first part of the study focuses on the structural system-level response of highway bridges that incorporate a class of innovative connecting devices called the “V-connector,”, which can be used to connect two components in a structural system, e.g., the column and the bridge deck, or the column and its foundation. This device, designed by ACII, Inc., results in an isolation surface at the connection plane via a connector rod placed in a V-shaped tube that is embedded into the concrete. Energy dissipation is provided by friction between a special washer located around the V-shaped tube and a top plate. Because of the period elongation due to the isolation layer and the limited amount of force transferred by the relatively flexible connector rod, bridge columns are protected from experiencing damage, thus leading to improved seismic behavior. The V-connector system also facilitates the ABC by allowing on-site assembly of prefabricated structural parts including those of the V-connector. A single-column, two-span highway bridge located in Northern California was used for the proof-of-concept of the proposed V-connector protective system. The V-connector was designed to result in an elastic bridge response based on nonlinear dynamic analyses of the bridge model with the V-connector. Accordingly, a one-third scale V-connector was fabricated based on a set of selected design parameters. A quasi-static cyclic test was first conducted to characterize the force-displacement relationship of the V-connector, followed by a hybrid simulation (HS) test in the longitudinal direction of the bridge to verify the intended linear elastic response of the bridge system. In the HS test, all bridge components were analytically modeled except for the V-connector, which was simulated as the experimental substructure in a specially designed and constructed test setup. Linear elastic bridge response was confirmed according to the HS results. The response of the bridge with the V-connector was compared against that of the as-built bridge without the V-connector, which experienced significant column damage. These results justified the effectiveness of this innovative device. The second part of the study presents the HS test conducted on a one-third scale two-column bridge bent with self-centering columns (broadly defined as “resilient columns” in this study) to reduce (or ultimately eliminate) any residual drifts. The comparison of the HS test with a previously conducted shaking table test on an identical bridge bent is one of the highlights of this study. The concept of resiliency was incorporated in the design of the bridge bent columns characterized by a well-balanced combination of self-centering, rocking, and energy-dissipating mechanisms. This combination is expected to lead to minimum damage and low levels of residual drifts. The ABC is achieved by utilizing precast columns and end members (cap beam and foundation) through an innovative socket connection. In order to conduct the HS test, a new hybrid simulation system (HSS) was developed, utilizing commonly available software and hardware components in most structural laboratories including: a computational platform using Matlab/Simulink [MathWorks 2015], an interface hardware/software platform dSPACE [2017], and MTS controllers and data acquisition (DAQ) system for the utilized actuators and sensors. Proper operation of the HSS was verified using a trial run without the test specimen before the actual HS test. In the conducted HS test, the two-column bridge bent was simulated as the experimental substructure while modeling the horizontal and vertical inertia masses and corresponding mass proportional damping in the computer. The same ground motions from the shaking table test, consisting of one horizontal component and the vertical component, were applied as input excitations to the equations of motion in the HS. Good matching was obtained between the shaking table and the HS test results, demonstrating the appropriateness of the defined governing equations of motion and the employed damping model, in addition to the reliability of the developed HSS with minimum simulation errors. The small residual drifts and the minimum level of structural damage at large peak drift levels demonstrated the superior seismic response of the innovative design of the bridge bent with self-centering columns. The reliability of the developed HS approach motivated performing a follow-up HS study focusing on the transverse direction of the bridge, where the entire two-span bridge deck and its abutments represented the computational substructure, while the two-column bridge bent was the physical substructure. This investigation was effective in shedding light on the system-level performance of the entire bridge system that incorporated innovative bridge bent design beyond what can be achieved via shaking table tests, which are usually limited by large-scale bridge system testing capacities.