Title: Stress-Strain Response and Fracture of Concrete in Biaxial Loading

Author(s): M. Ebrahim Tasuji, Floyd 0. Slate, and Arthur H. Nilson

Publication: Journal Proceedings

Volume: 75

Issue: 7

Appears on pages(s): 306-312

Keywords: biaxial loads; compressive strength: concretes;deformation; failure mechanisms; microcracking; strains;stress-strain relationships; tensile properties; tensile strength.

DOI: 10.14359/10944

Date: 7/1/1978

Abstract:
Thin plain concrete plates subject to biaxial loading were studied experimentally. All combinations of compressive and tensile loadings were included. Deformational characteristics, fracture mechanism, and strength were observed. Results confirm that concrete possesses higher strength in biaxial compression than in uniaxial compression. Under combined compression and tension, the compressive strength decreases almost linearly as the tensile stress increases. The biaxial tensile strength of concrete is greater than its uniaxial tensile strength. Observed modes of failure and measurements of tensile deformation enforce the idea that the most appropriate concrete failure criterion, for uniaxial and biaxial states of stress, is limiting tensile strain. The magnitude of the limiting tensile strain decreases with the degree of direct tensile loading involved and increases with the degree of compression. A general stress-strain relationship for concrete in biaxial loading is proposed. In addition, a simple biaxial strength criterion is recommended for practical application.