Title: Failure Mechanism of Reinforced Concrete Under Cyclic Loading

Author(s): T. C. Hsu and M. Y. Mansour

Publication: Symposium Paper

Volume: 206

Issue:

Appears on pages(s): 1-24

Keywords: cyclic loading, mechanism, pinching, reinforced concrete, shear, strain, steel, stress, softened truss models

DOI: 10.14359/12242

Date: 4/1/2002

Abstract:
The load-deformation response of R/C membrane elements (panels) subjected to reversed cyclic shear shows that the orientation of the steel bars with respect to the principal coordinate of the applied stresses has a strong effect on the "pinched shape" of the post-yield hysteretic loops. When the steel bars in a panel are oriented in the coordinate of the applied principal stresses, there is no "pinching effect," and the panel exhibits ductile behavior and high capacity of energy dissipation. Whereas, when the steel bars are oriented at an angle of 45 degrees to the applied principal stresses, severe pinching effect is observed and the panel becomes more brittle. This paper presents concisely a rational theory, called the Cyclic Softened Membrane Model (CSMM). This new rational theory is capable of predicting the entire history of the hysteretic loops (pre-and post-yeild); can explain the mechanism behind the "pinching effect"; and can elucidate the failure mechanism that causes the deteriorations of reinforced concrete structures under cyclic loading.