The Experts below are selected from a list of 3318 Experts worldwide ranked by ideXlab platform
Ali N Algemeel - One of the best experts on this subject based on the ideXlab platform.
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experimental investigation of basalt textile reinforced Engineered Cementitious Composite under apparent hoop tensile loading
Journal of building engineering, 2019Co-Authors: Ali N Algemeel, Yan Zhuge, Osama YoussfAbstract:Abstract Over the past decade, conventional mortar reinforced by textile has shown a promising performance as a Composite material for repairing of both concrete and masonry structures compared with that of reinforced by discrete fibres. However, the relatively brittleness of the conventional mortar adversely affects the efficiency of the textile reinforced mortar (TRM) Composite system due to the premature textile fracture. Engineered Cementitious Composite (ECC) is a well-known high-performance Cementitious Composite for its superior tensile strain-hardening properties and high impact resistance compared with both conventional mortar and discrete fibres reinforced mortar. In this paper, the behaviour of ECC reinforced by basalt textile was investigated and compared with that of TRM technique. The behaviour of ring-shaped specimens subjected to apparent hoop tensile loading was studied. The response characteristics including: tensile strength, failure modes, energy absorption, toughness index, strain behaviour, and the correlations between tensile strength and energy absorption were investigated. The results revealed that ECC is a promising material that can effectively enhance the performance of textile reinforced mortar. Replacing conventional mortar by ECC resulted in a notable increase in the peak tensile load by 241% indicating a dramatic effect of the ECC-based matrix.
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using textile reinforced Engineered Cementitious Composite for concrete columns confinement
Composite Structures, 2019Co-Authors: Ali N Algemeel, Yan ZhugeAbstract:Abstract Confining concrete structures with fibre reinforced polymer (FRP) is proven to be an efficient technique in improving the dilation and axial performance of concrete columns. However, a few drawbacks of using FRP, such as brittleness of FRP sheet and poor performance of the material at high temperatures, have been found in recent years. A feasibility study of a newly developed strengthening system, basalt fibre textile reinforced Engineered Cementitious Composite (ECC), is presented in this paper. A combination of basalt textile and ECC-based matrix was used in this research to evaluate how effectively this technique to confine concrete columns. All the specimens were tested under axial load, which was applied to the concrete cores only to create pure hoop tensile stress at the confinement layer. The experimental results revealed that ECC is a promising material that can effectively bond to textile fibres. A new confinement model was also developed to predict the compressive strength for textile reinforced ECC confined concrete. The technique could be an effective alternative to overcome the drawbacks of the traditional strengthening methods.
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experimental investigation of textile reinforced Engineered Cementitious Composite ecc for square concrete column confinement
Construction and Building Materials, 2018Co-Authors: Ali N Algemeel, Yan ZhugeAbstract:Abstract Confining concrete elements with fibre reinforced polymer (FRP) is proven to be an efficient technique in improving the dilation and axial performance of concrete columns. However, its effectiveness is reduced significantly for non-circular columns. In addition, a few drawbacks of using FRP, such as brittleness of FRP sheet and poor performance of the epoxy resins at high or low temperatures, have been found in recently year. This paper presents a feasibility investigation of a newly developed strengthening system, basalt fibre textile reinforced Engineered Cementitious Composite (ECC). Three types of basalt fibre textile were used, in combination with ECC to confine square concrete columns. The experimental results revealed that the new strengthening system has significantly enhanced the load carrying capacity and ductility of square concrete columns compared to the unconfined specimens and the specimens confined with textile reinforced mortars (TRM); the axial compressive strength increased in the range of 54%–77% for the new strengthening system compared to 41% for the TRM system. The results also shown that ECC itself could be used as a new retrofitting material in column confinement.
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use of hollow glass microspheres and hybrid fibres to improve the mechanical properties of Engineered Cementitious Composite
Construction and Building Materials, 2018Co-Authors: Ali N Algemeel, Yan Zhuge, Osama YoussfAbstract:Abstract Engineered Cementitious Composite (ECC) is a well-known high performance Cementitious Composites for its superior strain-hardening properties and high impact resistance. ECC has been produced using single type of fibre (mono-fibre). However, producing ECC using hybrid-fibre and as a lightweight construction material is in need for investigation. This paper describes the mechanical properties of ECC containing hollow glass microspheres (HGM) and hybrid-fibre consisted of polyvinyl alcohol (PVA) fibre and steel fibre (SF). The variables in this study were the HGM content (0% and 10%) and the hybrid-fibre volume fraction proportions (PVA : SF of 2.0% : 0.0%, 1.75% : 0.25%, 1.50% : 0.50%, and 1.25% : 0.75%). Compressive strength, flexural behaviour, energy absorption including first crack energy absorption were measured for the proposed Cementitious Composites. This study aimed at developing a new class of ECC with less unit weight, high-energy dissipation and ductility compared to conventional ECC. The results showed that mono-fibre ECC (PVA : SF is 2.0% : 0.0%) had higher compressive and flexural strengths than those showed by hybrid-fibre ECC mixtures. The ratio (PVA/SF) of 3.0 displayed the highest flexural strength compared to other hybrid-fibre ECC. The compressive and flexural strength of ECC was found to decrease with using HGM, although some lightweight ECC matrixes were deemed viable. Enhancements in compressive and flexural strength with further decrease in unit weight were achieved while w/b ratio decreased from 0.56 to 0.45.
Jun Zhang - One of the best experts on this subject based on the ideXlab platform.
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Effect of multiple matrix cracking on crack bridging of fiber reinforced Engineered Cementitious Composite
Journal of Composite Materials, 2020Co-Authors: Xuan Zheng, Jun Zhang, Zhenbo WangAbstract:In the present paper, a modified micromechanics based model that describes the crack bridging stress in randomly oriented discontinuous fiber reinforced Engineered Cementitious Composite is develop...
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zeolite to improve strength shrinkage performance of high strength Engineered Cementitious Composite
Construction and Building Materials, 2020Co-Authors: Qing Wang, Jun ZhangAbstract:Abstract Engineered Cementitious Composite (ECC) is a class of high-performance material because it displays strain hardening by multiple crack formation under tension. This unique property makes ECC an ideal constructional binding mortar or repairing material particularly for concrete cracks in existing structures. However, a major issue of ECC is the high shrinkage, which creates differential shrinkage and extra tensile stress that adversely affects its durability. To mitigate shrinkage, a novel way of using zeolite as an internal curing agent without sacrificing the strength of ECC is herein advocated. Zeolite is structurally porous that can trap water and act as a water reservoir to increase internal relative humidity (IRH). In this paper, the shrinkage, IRH and compressive strength of ECC containing 15% (18%), 20% (24%), and 30% (36%) of zeolite replacing quartz sand by weight (and by volume) is studied experimentally. Test results indicate that the 28-day total shrinkage of ECC decreases with the zeolite replacement ratio. From the shrinkage-to-strength ratio, it shows that ECC with 30% zeolite yields the lowest shrinkage per compressive strength, and hence the optimal ratio for quartz sand replacement in this study. With the beneficial effect observed, zeolite replacement ratio greater than 30% (36%) is recommended for future study on shrinkage reduction of ECC.
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flexural performance of high strength Engineered Cementitious Composite steel beam coupling with shrinkage load
Construction and Building Materials, 2018Co-Authors: Xuan Zheng, Jun Zhang, Qing Wang, Jiansheng FanAbstract:Abstract With increase of traffic volume, orthotropic steel deck stiffened with a Cementitious Composite overlay becomes a popular deck type in long-span bridge. In this paper, flexural performance of high strength Engineered Cementitious Composite (HSECC)-steel Composite beam, especially the effect of internal curing of HSECC on cracking load, ultimate load, deflection and crack opening under load, is studied by experiments. In the test program, five mixtures of HSECC, including four mixtures internally cured (IC) with pre-wetted calcined particles and one mixture with ordinary curing (OC), are used. The test results show that cracking and ultimate bending load of internally cured HSECC-steel Composite beam is greater than that of ordinarily cured Composite beam. Deflection at cracking and peak load of internally cured Composite beam is larger than that of the beam with ordinarily cured HSECC. Internal curing can also improve the ability of crack opening control after cracking. Reduction on shrinkage stress resulting from shrinkage of the cement Composite layer in the structure should be responsible for the positive effect on bending performance of HSECC-steel Composite beam.
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evaluation of shrinkage induced cracking performance of low shrinkage Engineered Cementitious Composite by ring tests
Composites Part B-engineering, 2013Co-Authors: Jun Zhang, Zhenbo WangAbstract:Abstract In this study, shrinkage induced cracking performance of low shrinkage Engineered Cementitious Composite (LSECC) and traditional ECC is evaluated comparatively by ring tests. The development of free shrinkage and interior humidity of LSECC and traditional ECC under plastic film sealed and drying conditions were experimentally measured. The anti-cracking performance of both materials under shrinkage load was examined with ring tests by measuring the compressive strain along circle direction in the steel ring and by observation on the ring specimen. The experimental results show that the shrinkage of LSECC is significantly reduced comparing with that of traditional ECC. Under the same restraint and environmental drying conditions, LSECC presents super anti-cracking performance that behaves as no visible cracks on the ring specimen can be observed. By contrast, there are number of fine cracks are observed on traditional ECC specimen. The mechanisms of super anti-cracking performance of LSECC are interpreted by shrinkage induced stress analyses with ECC-steel Composite ring specimen.
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Engineered Cementitious Composite with characteristic of low drying shrinkage
Cement and Concrete Research, 2009Co-Authors: Jun Zhang, Cheng Xu Gong, Zili Guo, Minghua ZhangAbstract:Abstract This paper reports a new class of Engineered Cementitious Composite (ECC) with characteristics of low drying shrinkage, tight crack opening and high tensile strain capacity. Research emphasis is placed on the influence of different Cementitious matrix on drying shrinkage, tensile property and early age cracking behavior of the Composites. Experimental results show that drying shrinkage of the Composite is greatly reduced as using the low shrinkage Cementitious material in matrix, while the Composite remains strain-hardening and multiple cracking characteristics. The measured drying shrinkage strain at 28 days is only 109 × 10− 6 to 242 × 10− 6 for low shrinkage ECCs. For traditional ECC, the shrinkage strain at 28 days is nearly 1200 × 10− 6. The average tensile strain capacity after 28 days curing is 2.5% of the low shrinkage ECC with tensile strength of 4–5 MPa. Further, in the strain-hardening and multiple cracking stage, cracks with much smaller width compared to the traditional ECC are formed in the low shrinkage ECC.
Shwan H Said - One of the best experts on this subject based on the ideXlab platform.
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structural behavior of rc Engineered Cementitious Composite ecc exterior beam column joints under reversed cyclic loading
Construction and Building Materials, 2016Co-Authors: Shwan H Said, Hashim Abdul RazakAbstract:Abstract This paper investigates the effects of Engineered Cementitious Composite (ECC) on the behavior of RC exterior beam–column joint under reversed cyclic loading. The main parameters considered include the load–deflection relationship, crack propagation, moment–rotation relationship at the joint, and energy absorption capacity. The experimental work was conducted on a normal concrete and an ECC full scale RC exterior beam–column joint. The specimen was subjected to reverse cyclic loading under controlled deformation at the tip of the beam until failure. At post cracking stages, the ECC joint showed significant improvement in the ultimate shear and moment capacities, as well as in the deformation behavior and damage tolerance, compared with the NC specimen at ultimate and failure stages. Numerous tiny cracks with reduced crack width and spacing forming a dense of network propagated within the joint region.
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the effect of synthetic polyethylene fiber on the strain hardening behavior of Engineered Cementitious Composite ecc
Materials & Design, 2015Co-Authors: Shwan H Said, Hashim Abdul RazakAbstract:Abstract This research investigated the effects of polyethylene (PE) fibers on the toughness and compressive and flexural strengths of Engineered Cementitious Composite (ECC) cubes and slabs. In particular, this study discussed the reinforcing index (R.I.) as the main parameter. Tests were conducted in direct tension to evaluate the strain-hardening behavior of ECC with different PE fiber contents. Flexural toughness was also assessed following the ASTM C1018 procedure and post-cracking strength technique (PCS m ). Results showed that the compressive strength linearly decreased with the increase of the reinforcing index, which in turn decreased the first crack load and significantly increased the ultimate load and failure deflections, and the ultimate strength of slabs. The toughness indices I 20 to I 100 significantly increased with the increase in reinforcing index and even exceeded the considered limitations. Based on the observed results, a new definition for the ECC PE was proposed as an extension to the definition given in ASTM C1018. All the residual strength factors increased when the reinforcing index increased, indicating a higher amount of the retained strength. Similarly, the retained strength had a higher amount when the PCS 24 values increased with increase in the reinforcing indices.
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Strength and deformation characteristics of Engineered Cementitious Composite slabs with different polymer fibres
Journal of Reinforced Plastics and Composites, 2015Co-Authors: Shwan H Said, Hashim Abdul Razak, Ismail OthmanAbstract:This paper presents a study on the compressive and flexural strength of Engineered Cementitious Composite (ECC) cubes and slabs, reinforced with various polymer fibres. The type of fibre, fibre con...
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flexural behavior of Engineered Cementitious Composite ecc slabs with polyvinyl alcohol fibers
Construction and Building Materials, 2015Co-Authors: Shwan H Said, Hashim Abdul Razak, Ismail OthmanAbstract:Abstract This paper investigates the effects of polyvinyl alcohol (PVA) fibers on the toughness, compressive and flexural strength of Engineered Cementitious Composite (ECC) cubes and slabs. The key parameter discussed in this study is the reinforcing index. To evaluate the strain-hardening behavior of ECC with different PVA fiber contents, tests were conducted in direct tension. Flexural toughness was also evaluated following ASTM C 1018 procedure and post-cracking strength technique (PCSm). Results showed that the compressive strength decreases as the reinforcing index increases in a nonlinear trend. By increasing the reinforcing index, the first crack load decreases and ultimate strength slightly increases. Furthermore, a significant increase in the first crack strength was obtained by an excess value 1000 of the reinforcing index. There is a significant increase in the deflection at ultimate load and the deflection at failure as the reinforcing index increases in a linear manner. The strain-hardening and multiple cracking behavior were observed for slabs with reinforcing indices higher than 316 whereas the softening behavior was observed for lesser values. The ECC PVA slabs did not attain the desired ductility due to the rupture of PVA fibers. A significant increase has occurred to the toughness indices I20, I30 and I40 with the increase in reinforcing index. Moreover, the indices exceed the limitations considered. A new definition as an extension to the definition given in ASTM C 1018 was proposed for ECC PVA material according to the observed results. All the residual strength factors increased as the reinforcing index increases which indicates a higher amount of strength retained. The PCS60 values increased with increase in the reinforcing indices. Thus, the increase in PCS60 values indicates higher flexural performance, better ductility and energy absorption capacity for slabs.
Yan Zhuge - One of the best experts on this subject based on the ideXlab platform.
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experimental investigation of basalt textile reinforced Engineered Cementitious Composite under apparent hoop tensile loading
Journal of building engineering, 2019Co-Authors: Ali N Algemeel, Yan Zhuge, Osama YoussfAbstract:Abstract Over the past decade, conventional mortar reinforced by textile has shown a promising performance as a Composite material for repairing of both concrete and masonry structures compared with that of reinforced by discrete fibres. However, the relatively brittleness of the conventional mortar adversely affects the efficiency of the textile reinforced mortar (TRM) Composite system due to the premature textile fracture. Engineered Cementitious Composite (ECC) is a well-known high-performance Cementitious Composite for its superior tensile strain-hardening properties and high impact resistance compared with both conventional mortar and discrete fibres reinforced mortar. In this paper, the behaviour of ECC reinforced by basalt textile was investigated and compared with that of TRM technique. The behaviour of ring-shaped specimens subjected to apparent hoop tensile loading was studied. The response characteristics including: tensile strength, failure modes, energy absorption, toughness index, strain behaviour, and the correlations between tensile strength and energy absorption were investigated. The results revealed that ECC is a promising material that can effectively enhance the performance of textile reinforced mortar. Replacing conventional mortar by ECC resulted in a notable increase in the peak tensile load by 241% indicating a dramatic effect of the ECC-based matrix.
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using textile reinforced Engineered Cementitious Composite for concrete columns confinement
Composite Structures, 2019Co-Authors: Ali N Algemeel, Yan ZhugeAbstract:Abstract Confining concrete structures with fibre reinforced polymer (FRP) is proven to be an efficient technique in improving the dilation and axial performance of concrete columns. However, a few drawbacks of using FRP, such as brittleness of FRP sheet and poor performance of the material at high temperatures, have been found in recent years. A feasibility study of a newly developed strengthening system, basalt fibre textile reinforced Engineered Cementitious Composite (ECC), is presented in this paper. A combination of basalt textile and ECC-based matrix was used in this research to evaluate how effectively this technique to confine concrete columns. All the specimens were tested under axial load, which was applied to the concrete cores only to create pure hoop tensile stress at the confinement layer. The experimental results revealed that ECC is a promising material that can effectively bond to textile fibres. A new confinement model was also developed to predict the compressive strength for textile reinforced ECC confined concrete. The technique could be an effective alternative to overcome the drawbacks of the traditional strengthening methods.
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experimental investigation of textile reinforced Engineered Cementitious Composite ecc for square concrete column confinement
Construction and Building Materials, 2018Co-Authors: Ali N Algemeel, Yan ZhugeAbstract:Abstract Confining concrete elements with fibre reinforced polymer (FRP) is proven to be an efficient technique in improving the dilation and axial performance of concrete columns. However, its effectiveness is reduced significantly for non-circular columns. In addition, a few drawbacks of using FRP, such as brittleness of FRP sheet and poor performance of the epoxy resins at high or low temperatures, have been found in recently year. This paper presents a feasibility investigation of a newly developed strengthening system, basalt fibre textile reinforced Engineered Cementitious Composite (ECC). Three types of basalt fibre textile were used, in combination with ECC to confine square concrete columns. The experimental results revealed that the new strengthening system has significantly enhanced the load carrying capacity and ductility of square concrete columns compared to the unconfined specimens and the specimens confined with textile reinforced mortars (TRM); the axial compressive strength increased in the range of 54%–77% for the new strengthening system compared to 41% for the TRM system. The results also shown that ECC itself could be used as a new retrofitting material in column confinement.
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use of hollow glass microspheres and hybrid fibres to improve the mechanical properties of Engineered Cementitious Composite
Construction and Building Materials, 2018Co-Authors: Ali N Algemeel, Yan Zhuge, Osama YoussfAbstract:Abstract Engineered Cementitious Composite (ECC) is a well-known high performance Cementitious Composites for its superior strain-hardening properties and high impact resistance. ECC has been produced using single type of fibre (mono-fibre). However, producing ECC using hybrid-fibre and as a lightweight construction material is in need for investigation. This paper describes the mechanical properties of ECC containing hollow glass microspheres (HGM) and hybrid-fibre consisted of polyvinyl alcohol (PVA) fibre and steel fibre (SF). The variables in this study were the HGM content (0% and 10%) and the hybrid-fibre volume fraction proportions (PVA : SF of 2.0% : 0.0%, 1.75% : 0.25%, 1.50% : 0.50%, and 1.25% : 0.75%). Compressive strength, flexural behaviour, energy absorption including first crack energy absorption were measured for the proposed Cementitious Composites. This study aimed at developing a new class of ECC with less unit weight, high-energy dissipation and ductility compared to conventional ECC. The results showed that mono-fibre ECC (PVA : SF is 2.0% : 0.0%) had higher compressive and flexural strengths than those showed by hybrid-fibre ECC mixtures. The ratio (PVA/SF) of 3.0 displayed the highest flexural strength compared to other hybrid-fibre ECC. The compressive and flexural strength of ECC was found to decrease with using HGM, although some lightweight ECC matrixes were deemed viable. Enhancements in compressive and flexural strength with further decrease in unit weight were achieved while w/b ratio decreased from 0.56 to 0.45.
Osama Youssf - One of the best experts on this subject based on the ideXlab platform.
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experimental investigation of basalt textile reinforced Engineered Cementitious Composite under apparent hoop tensile loading
Journal of building engineering, 2019Co-Authors: Ali N Algemeel, Yan Zhuge, Osama YoussfAbstract:Abstract Over the past decade, conventional mortar reinforced by textile has shown a promising performance as a Composite material for repairing of both concrete and masonry structures compared with that of reinforced by discrete fibres. However, the relatively brittleness of the conventional mortar adversely affects the efficiency of the textile reinforced mortar (TRM) Composite system due to the premature textile fracture. Engineered Cementitious Composite (ECC) is a well-known high-performance Cementitious Composite for its superior tensile strain-hardening properties and high impact resistance compared with both conventional mortar and discrete fibres reinforced mortar. In this paper, the behaviour of ECC reinforced by basalt textile was investigated and compared with that of TRM technique. The behaviour of ring-shaped specimens subjected to apparent hoop tensile loading was studied. The response characteristics including: tensile strength, failure modes, energy absorption, toughness index, strain behaviour, and the correlations between tensile strength and energy absorption were investigated. The results revealed that ECC is a promising material that can effectively enhance the performance of textile reinforced mortar. Replacing conventional mortar by ECC resulted in a notable increase in the peak tensile load by 241% indicating a dramatic effect of the ECC-based matrix.
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use of hollow glass microspheres and hybrid fibres to improve the mechanical properties of Engineered Cementitious Composite
Construction and Building Materials, 2018Co-Authors: Ali N Algemeel, Yan Zhuge, Osama YoussfAbstract:Abstract Engineered Cementitious Composite (ECC) is a well-known high performance Cementitious Composites for its superior strain-hardening properties and high impact resistance. ECC has been produced using single type of fibre (mono-fibre). However, producing ECC using hybrid-fibre and as a lightweight construction material is in need for investigation. This paper describes the mechanical properties of ECC containing hollow glass microspheres (HGM) and hybrid-fibre consisted of polyvinyl alcohol (PVA) fibre and steel fibre (SF). The variables in this study were the HGM content (0% and 10%) and the hybrid-fibre volume fraction proportions (PVA : SF of 2.0% : 0.0%, 1.75% : 0.25%, 1.50% : 0.50%, and 1.25% : 0.75%). Compressive strength, flexural behaviour, energy absorption including first crack energy absorption were measured for the proposed Cementitious Composites. This study aimed at developing a new class of ECC with less unit weight, high-energy dissipation and ductility compared to conventional ECC. The results showed that mono-fibre ECC (PVA : SF is 2.0% : 0.0%) had higher compressive and flexural strengths than those showed by hybrid-fibre ECC mixtures. The ratio (PVA/SF) of 3.0 displayed the highest flexural strength compared to other hybrid-fibre ECC. The compressive and flexural strength of ECC was found to decrease with using HGM, although some lightweight ECC matrixes were deemed viable. Enhancements in compressive and flexural strength with further decrease in unit weight were achieved while w/b ratio decreased from 0.56 to 0.45.
