Shear strength of normal and light weight reinforced concrete deep beams without web reinforcement

Abstract

There is no general consensus or accepted theory for evaluating the ultimate shear capacity of reinforced concrete beams without web reinforcement as a result the requirements in most of Codes of practice are provided in the form of empirical equations for predicting the shear capacity of reinforced concrete beams. In this paper, a study is conducted to evaluate the predictive accuracy of 6 empirical equations used in different Code of practice to predict the shear capacity of reinforced concrete slender beams. Empirical equations used in some Codes are identified to be superior to other equations. In addition, a study was also conducted to assess predictive accuracy of 17 empirical equations proposed in the literature by several researchers to predict the shear capacity of reinforced concrete slender beams. Among these 17 empirical equations some equations are identified to be superior to the other proposed equations. On the basis of experimental results of reinforced concrete beams having shear span to depth ratio a/d ≥2.5, empirical equations are proposed which include basic parameters i.e. concrete compressive strength, shear span to depth ratio and ratio of longitudinal reinforcement. The coefficient of correlation (COR) for proposed empirical equation for predicting the shear capacity of reinforced concrete beams having depth d < 300mm and d ≥ 300mm without web reinforcement comes out to be 0.869 and 0.953 respectively.