Papers by Keyword: Fiber Reinforced Cementitious Composite

Abstract: In this paper, a new green hybrid fibre-reinforced cementitious composite with high volume fly ash and steel and bagasse fibres is developed. High volume fly ash is used to partly replace cement and make the composite greener. Eco-friendly bagasse fibres from industrial waste and steel fibres are utilized to improve the mechanical behavior. In particularly, the influence of the parameters such as the sand/cement ratio and fly ash/cement ratio on the mechanical properties of the composite is investidated by evaluating the essential mechanical properties such as compressive strength and modulus of elasticity. The new green composite is found to be sustainable with high compressive. It is found that compressive strength of the composite decreases while the Young's modulus increases with the increase of the sand content, and that compressive strength and Youngs modulus of the composite decreases with the increase of the fly ash content.

Abstract: Engineered cementitious composite (ECC) is a representative of the new generation of high performance fiber reinforced cementitious composites. To reveal the influence of mineral admixtures on the tensile mechanical characteristics of polyvinyl alcohol fiber reinforced engineered cementitious composites (PVA-ECC), the tensile properties of PVA-ECC with replacing cement by a significant amount of fly ash (FA), silica fume (SF) and metakaolin (MK) was experimentally investigated. Uniaxial tensile experiment was carried out using rectangular thin plate with sizes of 400×100×15mm³. Results from uniaxial tensile tests show that these mineral admixtures can improve the properties of PVA-ECC. The composite can achieve an ultimate strain of 2.0%, as well as an ultimate strength of 4.0MPa, with a moderate fiber volume fraction of 2.0%. In addition, the composites with FA, SF and MK show saturated multiple cracking characteristics with crack width at ultimate strain limited to below 175μm.

Abstract: Ultra-high toughness cementitious composite (UHTCC) is a PVA fiber reinforced cementitious composite. Tensile strain hardening behavior with ultimate tensile strain of more 3% under direct tensile loading is one of its important characteristics. In the current article, nine simply-supported reinforced UHTCC beams were subjected to four-point bending loading to experimentally investigate the influence of ductile deformation behavior of UHTCC on ductility capacity of reinforced structural members. Ductility index is determined by adopting three different parameters, i.e., deformation capacity, energy dissipation capacity as well as curvature capacity. The effect of longitudinal tensile reinforcement ratios on the variation of ductility in UHTCC reinforced beams was examined. It was found from the experimental results that the combination of ductile matrix (UHTCC) and steel bar prevents from occurrence of localized cracks in pure bending zone, showing high damage tolerance and ductile failure behavior. The results also show that as longitudinal tensile reinforcement ratio increases, deformation ductility and curvature ductility both exponentially decrease while a small reduction is demonstrated for energy ductility at ultimate failure.

Abstract: This paper reports the tensile properties of a new class of engineered cementitious composite with characteristic of low drying shrinkage. 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 4-5MPa.