Biaxial Tension Stiffening due to Generally Oriented Reinforcing Layers

Abstract

Panel‐type concrete structures are generally reinforced with more than one layer of steel in different directions. The response of the panels under general states of in‐plane stress is a function of cracking and the degree‐of‐tension stiffening between the cracks. In this paper, a tension‐stiffening model, which accounts for multiple generally oriented reinforcing layers and cracks, is developed. The model is based on an equivalent reinforcing ratio normal to the crack, which maintains strain compatibility with the actual layers. An equivalent stress‐strain relation is developed for the equivalent layer. This relation is used in turn to develop the tension‐stiffening contribution across the crack. The model is implemented in a smeared‐crack concrete constitutive relation of the rotating‐crack type. This model is used within computer program FEPARCS to simulate the response of various panel specimens for which test results are available.