Evaluation of Shear Effect on Deflection of RC Beams

Abstract

This study evaluates the effect of shear on the deflection of reinforced concrete (RC) beams subjected to combined bending and shear. A total of nine simply supported beams were manufactured with the shear span-to-depth ratio, tension steel ratio, and shear capacity ratio as test variables. The experimental results were used to evaluate the effect of shear on the deflection by separating them into flexural and shear deformations. The theoretical deflection of the specimens was calculated using the effective moment of inertia equation recommended by ACI 318-19 based on the curvature relationships and experimental results of the flexure critical beams. By comparing the experimental and analytical results, it was revealed that the deflection obtained using the ACI equation underestimated the experimental results by up to about 1.6 times when the shear effect was large.

Flexural Response and Failure Analysis of Solid and Hollow Core Concrete Beams with Additional Opening at Different Locations

“…After the maximum load, the effect of shear on the load and deflection of the beam became obvious as the shear cracking started to deform. As the depth or width of TNSH increased, the shear strength of the beam section decreased, then its effect on increasing the deflection of the beam increased (these results agreed with those reported in [ 23 , 24 ]). As the size of the opening did not affect the shear capacity of the beam, the effect of shear on the total deflection of the beams could be neglected.…”

Prediction of Deflection of Reinforced Concrete Beams Considering Shear Effect

“…Kim et al [8] experimentally evaluated the effect of shear on the deflection of flexurecritical RC beams. As shown in Figure 2, the deflection at the mid-span of the beam can be obtained using (1) a linear variable differential transducer (LVDT) and (2) strain gauges attached to the mid-span of the beam.…”

“…In addition, the deviation between the deflection calculated using the current ACI code [7] and the experimental deflection measured from LVDT increased as the shear-to-depth ratio decreased, and the actual deflection was also underestimated. In this study, a new method to predict the deflection of flexure-critical RC beams is proposed based on the results of a previous study [8,9] that experimentally evaluated the effect of shear on the deflection of RC beams.…”

“…Table 1 shows the details and results of the specimens tested in the previous study [8,9]. The test variables were the shear span-to-depth ratio and shear capacity ratio V shear /V f lexure .…”

“…However, most studies on deflection have focused on flexure based on elastic theory, which implies that shear does not have a significant effect. Recently, Kim et al [8] experimentally separated and evaluated the effects of flexure and shear on deflection by conducting flexural tests of simply supported flexure-critical RC beams subjected to concentrated loads. Their results indicated that the deflection calculated using ACI 318-19 was similar to the deflection caused by flexure.…”