Experimental and numerical study on structural behavior of reactive powder concrete corbels without stirrups

Abstract

This paper presents a study that explores the application of reactive powder concrete (RPC), a modern construction material, to corbels without stirrups. The focus of the research is to investigate the shear behaviors of RPC corbels under vertical loading through experimental and numerical methods. Three RPC corbels with different shear span-to-effective depth ratios (av/d) of 0.6, 1.1, and 1.6 were tested. A commercial finite element method (FEM) code was utilized for the numerical analysis, and its accuracy was verified against the experimental results. A parametric study was conducted to evaluate the influence of various factors, including RPC compressive strength, RPC tensile strength, amount of main reinforcement, yield strength of main reinforcement, and stress-strain model of main reinforcement. Additionally, the shear strengths obtained from the tests were compared with the predicted values based on design codes, including ACI 318–14 and NF P18–710. The findings reveal that the av/d ratio significantly affected the load-deflection behaviors and failure modes of the RPC corbel specimens. The numerical model demonstrates good agreement with the experimental results. The RPC compressive strength emerges as the primary factor influencing the peak load of RPC corbels. Comparing various predictions, the Strut-and-Tie models recommended by the NF code exhibit the highest accuracy and safety in estimating the shear strengths of the RPC corbels.