COMPARATIVE STUDY OF ROTATING ANGLE-SOFTENED TRUSS MODEL AND MODIFIED COMPRESSION FIELD THEORY

Truss model, such as MCFT (modified compression field theory) and RA-STM (rotating angle-softened truss model), is among the most important developments in analyzing the shear and torsion behavior of reinforced concrete in the past thirty years. The governing equations of these two models are compared in this paper, and major difference is pointed out. By implementing them in general-purpose finite element program, the capability in predicting the shear behavior of reinforced concrete beam is then compared. Results show that the crack check in MCFT is unreasonable, and that the uniaxial concrete tensile stress-strain relationship is of key importance. A set of simple uniaxial stress-strain relationships for concrete and steel reinforcement is recommended.