Tension Stiffness Model for Cracked Reinforced Concrete

Abstract

It is known that the consideration of tension stiffening effect resulting from bond slip between reinforcement and surrounding concrete is very effective for the deformation analysis of reinforced concrete members. In the paper, the crack strain is defined as the derivative of the bond slip. Bond characteristics between the concrete and the steel are directly related to the crack spacing and crack width. The tension stiffening effect is derived to be evaluated by the factor λ. Furthermore, constitutive equations of composite materials of concrete and reinforcement in a two‐dimensional stress field with multiple‐crack orientation are developed, using stress reduction and reinforcement tensors. The proposed model can successfully represent the nonlinear behavior of multiple‐cracked reinforced concrete resulting from damage by cracking, etc., and is formulated so that the material tensors are directly applicable to nonlinear finite element analysis through the use of the concept of the smeared crack model. The experimental results are compared with the theoretical calculations. Reasonable agreement is obtained.