Analytical Study on Shear Capacity Evaluation of RC Beams with PVA Short Fiber

Abstract

This paper reports experimental and analytical results of shear capacity evaluation of concrete beams reinforced by PVA short fibers. Loading tests were carried out on various reinforced concrete beams with PVA short fibers of varying types and content, shear reinforcement ratios, effective depths, and shear span-to-effective depth ratios, a/d. The analysis was carried out using the tension-softening model obtained from the material test to simulate the beam shear tests. As a result of the investigation, it was confirmed that shear capacity is improved by mixing PVA short fibers in concrete and that the increase in shear capacity is governed by fiber content and beam effective depth. Further, effective fiber behavior was confirmed in beams showing the tied-arch resisting mechanism. As a result of analysis, it was confirmed that the effect of the tension-softening model for diagonal cracks was large in beams with a small a/d, and that the effect of the shear transfer model was large in beams with a large a/d. Based on comparison with experimental results, we recommend the combination of constitutive laws in the evaluation and analysis of the shear capacity of FRC beams.

Improving the algorithm of choosing spacing and number of stiff supports against a concentrated force in steel-concrete beams

“…Basic shear strength was determined from the intersection of the load and resistance curves. Experimental and theoretical studies in [24] were aimed at raising the shear resistance due to the use of short fibers in concrete. Thus, it can be asserted that much attention is paid to the issues of shear resistance in beams.…”

Punching Shear Capacity of Prestressed Concrete Slabs Made of Lightweight Concrete Mixed with Short Fibers

“…The results of this previous research showed that the load, loading point displacement, and the width of open cracks were obtained based on the bending test of 45 beams with notches, and a tensile softening model was constructed by the modified J-integral method. The remaining tensile strength was set at 8.5% of the tensile strength at a fiber content of 0.25 vol% and 17% at a fiber content of 0.5 vol% (Ito et al 2014). For the purpose of analyzing the sensitivity of lightweight aggregates and short fibers, the compression strength, Poisson's ratio, and compression strength reduction factor due to cracking were set to 56.7 N/mm 2 , 0.2, and 0.8, respectively.…”

“…Therefore, the authors have been researching means to provide light and very strong PC slabs using lightweight aggregate concrete mixed with short PVA fibers. The reason for focusing on short PVA fibers is that it has been confirmed that RC members have excellent shear capacity and durability (Ito et al 2014(Ito et al , 2018. Previous studies confirmed that PC slabs made of lightweight aggregate concrete mixed with 0.5 vol% of short PVA fibers (hereinafter, FLPC slab) results in a concrete density of 19.0 kN/m 3 or less even in one-way prestressed slabs, and that these slabs have the same punching shear capacity as those made of normal weight concrete (Kitano et al 2018).…”

Study on Performance of PVA Fiber Reinforced Concrete Exposed for 10 Years to Seawater Spray

“…On the other hand, test cases with fibers could sustain the load after the maximum load was reduced, and there was no exfoliation of concrete flakes until the loading was stopped when the displacement reached about 10 mm ( Table 1). Figure 20 shows the relationship between the load at which the relative displacement was 2 mm and the remaining tensile strength (stress at the turnoff point) (Ito et al 2014). Figure 21 shows the remaining tensile strength of tension-softening model for FRC.…”