Performance of Reinforced Engineered Cementitious Composite Beams

Abstract

Engineered Cementitious Composite (ECC) was recently developed and was reported to improve the strength, damage tolerance, ductility, energy dissipation capacity, and durability of components when compared to conventional reinforced concrete. A polyvinyl alcohol fiber reinforced engineered cementitious composite (PVA-ECC) using local ingredientsnamely local sand instead of using microsilica sandwas developed, aiming for tensile strain capacity matching that of steel reinforcement for commonly used reinforced concrete structures while reducing the cost. The main objectives of this research are to develop and validate a procedure for numerical modeling and structural analysis of PVA-ECC beams using local sand. Also, the research aims to study the effects of several parameters on the flexural and shear behaviors of PVA-ECC beams. The results of numerical study indicated that the PVA-ECC beams have excellent shear capacity that helps in decreasing shear reinforcement congestion in structural elements. Consequently, PVA-ECC with local sand is very useful for structural elements to resist seismic loads. Furthermore, the peak load is increased with increasing of longitudinal reinforcement ratio (µ) and with increasing of yielding stress. On the other hand, the peak load is decreased with increase of shear span-to-depth ratio (S/d) and the mid-span deflection at peak load is increased with the increasing of S/d in all cases. The stiffness of PVA-ECC is decreased with increasing of S/d and is slightly increased with increasing of µ values. Also, there are minor differences in stiffness when yielding stress of steel reinforcement is changed.

Numerical Simulation of Engineering Cementitious Composite Beams Strengthened with Fiber-Reinforced Polymer and Steel Bars

“…For all beams, the steel reinforcement yielded, while the axial stress in BFRP reinforcement ranged from 46% to 66% of its ultimate tensile strength (the axial stress for reinforcement is only shown in Figure 7b). It is observed that increasing the ECC layer decreased the formation of diagonal shear cracks, conforming to the findings in [31][32][33][34]. In all the beams, the cracks extended to the compression zone.…”