The Experts below are selected from a list of 35727 Experts worldwide ranked by ideXlab platform
Yuxi Zhao - One of the best experts on this subject based on the ideXlab platform.
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prediction of corrosion induced Concrete Cracking under external loading and stirrup constraint
Construction and Building Materials, 2021Co-Authors: Yuxi Zhao, Yifan Wang, Jianfeng DongAbstract:Abstract In this study, the corrosion-induced Concrete Cracking in three Concrete beams with stirrups under external loading coupled with accelerated corrosion was investigated. The experimental results reveals that the external loading leads to earlier corrosion-induced Concrete Cracking. The stirrup constraint was found to have a significant influence on both the distribution and propagation of Cracking and the longitudinal corrosion of steel. With quantitatively considering the effects of external loading and stirrups, an analytical model was developed to predict corrosion-induced Concrete Cracking and the results of which were shown to be in satisfactory agreement with experimental results.
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A study of the elastic moduli of corrosion products using nano-indentation techniques
Corrosion Science, 2012Co-Authors: Yuxi ZhaoAbstract:Abstract This paper aims to determine the elastic moduli of corrosion products using nano-indentation techniques. Nano-indentation techniques were performed to determine the elastic modulus of four corrosion products collected from various environments. The results show that the corrosion products between a steel bar and Concrete include the outer layer, which is the mill scale, and the inner layer, which is generated during the corrosion process and is considered to be the main reason for Concrete Cracking. The elastic modulus of the inner rust of S1, S2, S3 and S4 is 61, 86, 47 and 51 GPa, respectively.
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Experimental study of the modulus of steel corrosion in a Concrete port
Corrosion Science, 2012Co-Authors: Yuxi ZhaoAbstract:Abstract This paper aims to determine the mechanical behaviour of steel corrosion, which can be introduced into a Concrete Cracking model because of steel corrosion. Cyclic low-compression tests and oedometer tests were performed to analyse corrosion products collected from a reinforced Concrete port that had been used for 40 years in Japan. The results showed that steel corrosion is not a linear elastic material and the influence of Poisson’s ratio on the rust modulus is not significant. This study also found a value of 165 MPa to specifically describe the apparent modulus of the rust.
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damage analysis and Cracking model of reinforced Concrete structures with rebar corrosion
Corrosion Science, 2011Co-Authors: Yuxi Zhao, Weiliang JinAbstract:Abstract The damage of Concrete cover in reinforced Concrete structures induced by reinforcing steel corrosion is investigated in this study. The damage process of the Concrete cover can be divided into two distinct stages: the non-Cracking stage and the partial Cracking stage. An analytical model based on damage mechanics and elastic mechanics is developed to predict the Concrete Cracking due to steel corrosion. Based on this model, the expansive pressure and the radial loss of steel bar are discussed. Parametric studies are carried out to examine the effects of the correlative factors on the expansive pressure and the steel loss.
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composition and expansion coefficient of rust based on x ray diffraction and thermal analysis
Corrosion Science, 2011Co-Authors: Yuxi ZhaoAbstract:Abstract Corrosion production can make cracks in the Concrete cover. Because their volumes are higher than that of the original metal. Therefore, the rust expansion coefficient is one of the key parameters in Concrete Cracking model caused by steel corrosion. X-ray diffraction and the thermal analysis were used to characterize eight corrosion products collected from various different environments. The results show that the compositions and the expansion coefficients for rust samples are different due to their different servicing environments. The rust expansion coefficients corresponding to the different environments were proposed, which can be applied to steel corrosion induced Concrete Cracking model.
Arnaud Castel - One of the best experts on this subject based on the ideXlab platform.
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Effect of Various Supplementary Cementitious Materials on Early-Age Concrete Cracking
Journal of Materials in Civil Engineering, 2020Co-Authors: Inamullah Khan, Arnaud Castel, M.s.h. Khan, Raymond Ian GilbertAbstract:AbstractThis paper focuses on the effect of supplementary cementitious materials on early-age mechanical and viscoelastic properties of Concrete, restrained shrinkage-induced Cracking, and time to ...
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assessing immediate and time dependent instantaneous stiffness of cracked reinforced Concrete beams using residual cracks
Journal of Structural Engineering-asce, 2018Co-Authors: Lifeng Zhu, Arnaud Castel, R I GilbertAbstract:AbstractUnder normal in-service conditions, beams and slabs in reinforced Concrete structures are usually cracked. Concrete Cracking and steel-Concrete bond damage lead to an irreversible reduction...
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tensile creep and early age Concrete Cracking due to restrained shrinkage
Construction and Building Materials, 2017Co-Authors: Inamullah Khan, Arnaud Castel, R I GilbertAbstract:Abstract Concrete structures are prone to Cracking due to restraint provided to early age autogenous and drying shrinkage. In addition, the risk of early-age thermal Cracking is increased by increasing the degree of restraint to early-age thermal contraction. At this early-age, tensile creep plays a key role in relaxing shrinkage induced tensile stresses and delaying the time to Cracking. However, limited data are available concerning tensile creep of Concrete and the magnitude and rate of development of the early-age shrinkage of Concrete. As a consequence, restraint to shrinkage is often poorly modelled in structural design. In order to accurately quantify the early-age shrinkage and tensile creep of Concrete, a comprehensive experimental program is being conducted at the UNSW Centre for Infrastructure Engineering and Safety. Tensile creep is measured on dog-bone shaped specimens subjected to constant sustained tensile stress, while shrinkage is measured on identical unloaded specimens. Restrained ring tests were also performed to validate the tensile creep coefficients calculated from dog-bone specimens. A simple analytical procedure to accurately predict the degree of restraint and the tensile stresses in Concrete induced by shrinkage is described for the restrained ring specimens.
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Concrete Cracking due to chloride induced reinforcement corrosion influence of steel Concrete interface defects due to the top bar effect
European Journal of Environmental and Civil Engineering, 2012Co-Authors: R Zhang, Arnaud Castel, Raoul FrancoisAbstract:This article deals with the influence of the steel–Concrete interface condition on reinforcement corrosion and Concrete Cracking in a chloride environment. Four large Concrete members were cast with horizontal reinforcements at different levels in order to create voids under the upper horizontal bars due to the well-known ‘top-bar effect.’ Then, the members were sawn into smaller specimens that included one rebar. Specimens obtained were submitted to wetting–drying cycles in salt water (natural corrosion process) until Concrete Cracking was observed. Results show that before Concrete Cracking, the corrosion pattern observed is completely different between the specimens with defect (generalised corrosion) or without defect (local pitting corrosion). The Concrete Cracking is delayed for specimens affected by the ‘top-bar effect’ in spite of a higher corrosion rate, and occurs at a significantly higher corrosion rate. A new model for uniform steel cross-section reduction calculation from Concrete crack width...
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Concrete Cracking due to chloride-induced reinforcement corrosion – influence of steel–Concrete interface defects due to the ‘top-bar effect’
European Journal of Environmental and Civil Engineering, 2012Co-Authors: R Zhang, Arnaud Castel, Raoul FrancoisAbstract:This article deals with the influence of the steel–Concrete interface condition on reinforcement corrosion and Concrete Cracking in a chloride environment. Four large Concrete members were cast with horizontal reinforcements at different levels in order to create voids under the upper horizontal bars due to the well-known ‘top-bar effect.’ Then, the members were sawn into smaller specimens that included one rebar. Specimens obtained were submitted to wetting–drying cycles in salt water (natural corrosion process) until Concrete Cracking was observed. Results show that before Concrete Cracking, the corrosion pattern observed is completely different between the specimens with defect (generalised corrosion) or without defect (local pitting corrosion). The Concrete Cracking is delayed for specimens affected by the ‘top-bar effect’ in spite of a higher corrosion rate, and occurs at a significantly higher corrosion rate. A new model for uniform steel cross-section reduction calculation from Concrete crack width in case of ‘Top-bar effect’ is proposed.
Mir Shahnewaz Arefin - One of the best experts on this subject based on the ideXlab platform.
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Study of the thermal stress development of asphalt mixtures using the Asphalt Concrete Cracking Device (ACCD)
Construction and Building Materials, 2016Co-Authors: Moses Akentuna, Sang-soo Kim, Ala R. Abbas, Munir D. Nazzal, Mir Shahnewaz ArefinAbstract:Abstract Asphalt pavements exposed to colder temperatures may crack when higher thermal stresses are induced in them. The Asphalt Concrete Cracking Device (ACCD) is a test method developed as a simpler alternative to the thermal stress retrained specimen test (TSRST) for Cracking temperature determination. This study was conducted to investigate asphalt mixture properties influencing thermal stress development within the ACCD. Asphalt mixture properties investigated included: asphalt binder grade, the addition of recycled materials (RAP and RAS), air void content, aggregate/mixture thermal expansion coefficient (CTE) and binder content. The aforementioned mixture properties investigated were all found to influence thermal stress development.
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Study of the thermal stress development of asphalt mixtures using the Asphalt Concrete Cracking Device (ACCD)
Construction and Building Materials, 2016Co-Authors: Moses Akentuna, Sang-soo Kim, Ala R. Abbas, Munir D. Nazzal, Mir Shahnewaz ArefinAbstract:Abstract Asphalt pavements exposed to colder temperatures may crack when higher thermal stresses are induced in them. The Asphalt Concrete Cracking Device (ACCD) is a test method developed as a simpler alternative to the thermal stress retrained specimen test (TSRST) for Cracking temperature determination. This study was conducted to investigate asphalt mixture properties influencing thermal stress development within the ACCD. Asphalt mixture properties investigated included: asphalt binder grade, the addition of recycled materials (RAP and RAS), air void content, aggregate/mixture thermal expansion coefficient (CTE) and binder content. The aforementioned mixture properties investigated were all found to influence thermal stress development.
R I Gilbert - One of the best experts on this subject based on the ideXlab platform.
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assessing immediate and time dependent instantaneous stiffness of cracked reinforced Concrete beams using residual cracks
Journal of Structural Engineering-asce, 2018Co-Authors: Lifeng Zhu, Arnaud Castel, R I GilbertAbstract:AbstractUnder normal in-service conditions, beams and slabs in reinforced Concrete structures are usually cracked. Concrete Cracking and steel-Concrete bond damage lead to an irreversible reduction...
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tensile creep and early age Concrete Cracking due to restrained shrinkage
Construction and Building Materials, 2017Co-Authors: Inamullah Khan, Arnaud Castel, R I GilbertAbstract:Abstract Concrete structures are prone to Cracking due to restraint provided to early age autogenous and drying shrinkage. In addition, the risk of early-age thermal Cracking is increased by increasing the degree of restraint to early-age thermal contraction. At this early-age, tensile creep plays a key role in relaxing shrinkage induced tensile stresses and delaying the time to Cracking. However, limited data are available concerning tensile creep of Concrete and the magnitude and rate of development of the early-age shrinkage of Concrete. As a consequence, restraint to shrinkage is often poorly modelled in structural design. In order to accurately quantify the early-age shrinkage and tensile creep of Concrete, a comprehensive experimental program is being conducted at the UNSW Centre for Infrastructure Engineering and Safety. Tensile creep is measured on dog-bone shaped specimens subjected to constant sustained tensile stress, while shrinkage is measured on identical unloaded specimens. Restrained ring tests were also performed to validate the tensile creep coefficients calculated from dog-bone specimens. A simple analytical procedure to accurately predict the degree of restraint and the tensile stresses in Concrete induced by shrinkage is described for the restrained ring specimens.
Moses Akentuna - One of the best experts on this subject based on the ideXlab platform.
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Study of the thermal stress development of asphalt mixtures using the Asphalt Concrete Cracking Device (ACCD)
Construction and Building Materials, 2016Co-Authors: Moses Akentuna, Sang-soo Kim, Ala R. Abbas, Munir D. Nazzal, Mir Shahnewaz ArefinAbstract:Abstract Asphalt pavements exposed to colder temperatures may crack when higher thermal stresses are induced in them. The Asphalt Concrete Cracking Device (ACCD) is a test method developed as a simpler alternative to the thermal stress retrained specimen test (TSRST) for Cracking temperature determination. This study was conducted to investigate asphalt mixture properties influencing thermal stress development within the ACCD. Asphalt mixture properties investigated included: asphalt binder grade, the addition of recycled materials (RAP and RAS), air void content, aggregate/mixture thermal expansion coefficient (CTE) and binder content. The aforementioned mixture properties investigated were all found to influence thermal stress development.
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Study of the thermal stress development of asphalt mixtures using the Asphalt Concrete Cracking Device (ACCD)
Construction and Building Materials, 2016Co-Authors: Moses Akentuna, Sang-soo Kim, Ala R. Abbas, Munir D. Nazzal, Mir Shahnewaz ArefinAbstract:Abstract Asphalt pavements exposed to colder temperatures may crack when higher thermal stresses are induced in them. The Asphalt Concrete Cracking Device (ACCD) is a test method developed as a simpler alternative to the thermal stress retrained specimen test (TSRST) for Cracking temperature determination. This study was conducted to investigate asphalt mixture properties influencing thermal stress development within the ACCD. Asphalt mixture properties investigated included: asphalt binder grade, the addition of recycled materials (RAP and RAS), air void content, aggregate/mixture thermal expansion coefficient (CTE) and binder content. The aforementioned mixture properties investigated were all found to influence thermal stress development.