Title: Behavior of Reinforced Concrete Membrane Elements in Shear

Author(s): Xiao-Bo David Pang and Thomas T. C. Hsu

Publication: Structural Journal

Volume: 92

Issue: 6

Appears on pages(s): 665-679

Keywords: compatibility methods; equilibrium; failure; membranes; rein-forced concrete; shear properties; shear stress; strains; stresses; stress-strain relationships; trusses.

DOI: 10.14359/9661

Date: 11/1/1995

Abstract:
Thirteen full-size reinforced concrete panels were tested to determine the behavior of reinforced concrete elements subjected to membrane shear. The panels were designed to study three variables: 1) the percentage of rein-forcement, 2) the ratio of transverse-to-longitudinal steel, and 3) the load path. The resulting load-deformation responses in the test panels were cor-rectly predicted by a softened truss model. This rational model satisfies the three fundamental principles of the mechanics of materials: 1) stress equi-librium, 2) strain compatibility, and 3) the constitutive laws of materials. Three constitutive laws previously established from membrane elements subjected to biaxial tension-compression were applied to membrane ele-ments subjected to shear: It was found that the constitutive law of reinforc-ing bars must be modified by a factor that takes into account the “kinking” of the reinforcing bars. Membrane elements subjected to shear may fail in four modes: 1) under-reinforced, 2) partially under-reinforced in longitudinal steel, 3) partially under-reinforced in transverse steel, or 4) over-reinforced. These four fail-ure modes are also correctly predicted by the softened truss model.