The Experts below are selected from a list of 11475 Experts worldwide ranked by ideXlab platform
Farhad Aslani - One of the best experts on this subject based on the ideXlab platform.
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Durability Assessment of concrete containing surface pretreated coarse recycled concrete aggregates
Construction and Building Materials, 2020Co-Authors: Hossein Sasanipour, Farhad AslaniAbstract:Abstract Recycled aggregate concrete (RAC) made with recycled concrete aggregates (RCA) is different from conventional concrete cast with natural aggregates due to the adhered cement mortar on RCAs to the former. Hence, the properties of concrete especially Durability are expected to be affected when the RCAs are incorporated in the concrete mix. In this paper, two surface pretreatment methods were investigated to enhance the properties of RCAs and the Durability performance of mixes was studied. The RCAs were coated by silica fume slurry manually and in the desiccator, namely RACCM and RACCD methods, respectively. The replacement level of coarse RCAs was considered at 100% in the mixes. Furthermore, three effective water-to-cement ratios (0.30, 0.35, and 0.40) were used. Tests were undertaken to establish the compressive strength, ultrasonic pulse velocity (UPV), electrical resistivity (ER), and chloride ion penetration resistance of each mix. Results indicated that compressive strength declined with the incorporation of RCAs and both pretreatment methods obviously enhanced the ER and chloride ion penetration resistance, which was significantly governed by silica fume slurry. More interestingly, test results indicated that the surface treatment methods were effective in reducing total charge passed. The RACCM method showed relatively more efficient results than RACCD.
Hossein Sasanipour - One of the best experts on this subject based on the ideXlab platform.
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Durability Assessment of concrete containing surface pretreated coarse recycled concrete aggregates
Construction and Building Materials, 2020Co-Authors: Hossein Sasanipour, Farhad AslaniAbstract:Abstract Recycled aggregate concrete (RAC) made with recycled concrete aggregates (RCA) is different from conventional concrete cast with natural aggregates due to the adhered cement mortar on RCAs to the former. Hence, the properties of concrete especially Durability are expected to be affected when the RCAs are incorporated in the concrete mix. In this paper, two surface pretreatment methods were investigated to enhance the properties of RCAs and the Durability performance of mixes was studied. The RCAs were coated by silica fume slurry manually and in the desiccator, namely RACCM and RACCD methods, respectively. The replacement level of coarse RCAs was considered at 100% in the mixes. Furthermore, three effective water-to-cement ratios (0.30, 0.35, and 0.40) were used. Tests were undertaken to establish the compressive strength, ultrasonic pulse velocity (UPV), electrical resistivity (ER), and chloride ion penetration resistance of each mix. Results indicated that compressive strength declined with the incorporation of RCAs and both pretreatment methods obviously enhanced the ER and chloride ion penetration resistance, which was significantly governed by silica fume slurry. More interestingly, test results indicated that the surface treatment methods were effective in reducing total charge passed. The RACCM method showed relatively more efficient results than RACCD.
Neil C Hyatt - One of the best experts on this subject based on the ideXlab platform.
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reactive spark plasma sintering of cs exchanged chabazite characterisation and Durability Assessment for fukushima daiichi npp clean up
Journal of Nuclear Science and Technology, 2019Co-Authors: Liam C Harnett, Laura J Gardner, Shikuan Sun, Colleen Mann, Neil C HyattAbstract:Ion-specific media (ISM) have played an integral role in the clean-up and remediation efforts at the Fukushima Dai-ichi disaster site, through the processing of contaminated wastewaters. The use of...
Paulo B Lourenco - One of the best experts on this subject based on the ideXlab platform.
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debonding damage analysis in composite masonry strengthening systems with polymer and mortar based matrix by means of the acoustic emission technique
Smart Materials and Structures, 2016Co-Authors: Els Verstrynge, Bahman Ghiassi, Martine Wevers, Paulo B LourencoAbstract:Different types of strengthening systems, based on fiber reinforced materials, are under investigation for external strengthening of historic masonry structures. A full characterization of the bond behavior and of the short- and long-term failure mechanisms is crucial to ensure effective design, compatibility with the historic substrate and Durability of the strengthening solution. Therein, non-destructive techniques are essential for bond characterization, Durability Assessment and on-site condition monitoring. In this paper, the acoustic emission (AE) technique is evaluated for debonding characterization and localization on fiber reinforced polymer (FRP) and steel reinforced grout-strengthened clay bricks. Both types of strengthening systems are subjected to accelerated ageing tests under thermal cycles and to single-lap shear bond tests. During the reported experimental campaign, AE data from the accelerated ageing tests demonstrated the thermal incompatibility between brick and epoxy-bonded FRP composites, and debonding damage was successfully detected, characterized and located. In addition, a qualitative comparison is made with digital image correlation and infrared thermography, in view of efficient on-site debonding detection.
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FRP-to-Masonry Bond Durability Assessment with Infrared Thermography Method
Journal of Nondestructive Evaluation, 2014Co-Authors: Bahman Ghiassi, Sandra M. Silva, Daniel V. Oliveira, Paulo B Lourenco, Luís BragançaAbstract:The bond behavior between FRP composites and masonry substrate plays an important role in the performance of externally bonded reinforced masonry structures. Therefore, monitoring the bond quality during the application and subsequent service life of a structure is of crucial importance for execution control and structural health monitoring. The bond quality can change during the service life of the structure due to environmental conditions. Local detachments may occur at the FRP/substrate interface, affecting the bond performance to a large extent. Therefore, the use of expedite and efficient non-destructive techniques for Assessment of the bond quality and monitoring FRP delamination is of much interest. Active infrared thermography (IR) technique was used in this study for assessing the bond quality in environmentally degraded FRP-strengthened masonry elements. The applicability and accuracy of the adopted method was initially validated by localization and size quantification of artificially embedded defects in FRP-strengthened brick specimens. Then, the method was used for investigating the appearance and progression of FRP delaminations due to environmental conditions. GFRP-strengthened brick specimens were exposed to accelerated hygrothermal ageing tests and inspected periodically with the IR camera. The results showed environmental exposure may produce large progressive FRP delaminations.
Liam C Harnett - One of the best experts on this subject based on the ideXlab platform.
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reactive spark plasma sintering of cs exchanged chabazite characterisation and Durability Assessment for fukushima daiichi npp clean up
Journal of Nuclear Science and Technology, 2019Co-Authors: Liam C Harnett, Laura J Gardner, Shikuan Sun, Colleen Mann, Neil C HyattAbstract:Ion-specific media (ISM) have played an integral role in the clean-up and remediation efforts at the Fukushima Dai-ichi disaster site, through the processing of contaminated wastewaters. The use of...
