Cyclic Inelastic Strut-Tie Modeling of Shear-Critical Reinforced Concrete Members

摘要

When structural concrete members are subjected to a combination of shear and flexure, the behavior under lateral loading becomes complex and difficult to predict, even with sophisticated nonlinear finite element methods of analysis. As a way of resolving the situation, this paper introduces CIST (Cyclic Inelastic Strut-Tie) modeling and demonstrates the implementation of the technique with a general-purpose inelastic computer program. However, the proposed CIST technique requires the proper selection of element models and their dimensioning. For this, a numerical integration scheme is employed. In application of CIST modeling technique to shear-critical concrete members, the post-cracked state is considered. Element models for longitudinal and transverse reinforcing steel and concrete in a compression and tension are grouped as per the lateral loading direction to represent the shear and flexural components, connected together through the idealized nodes. The proposed CIST technique was validated against the experimentally observed behavior of shear-critical reinforced concrete members subjected to reversed cyclic lateral loading. It is demonstrated that the CIST modeling technique is able to capture the combined response of shear and flexure quite well.