Title:
Influence of Web Reinforcement on the Cyclic Response of
Structural Walls
Author(s):
Chadchart Sittipunt and Sharon L. Wood
Publication:
Structural Journal
Volume:
92
Issue:
6
Appears on pages(s):
745-756
Keywords:
cyclic loads; finite element method; hysteresis; shear proper-ties;
structural members; web reinforcement.
DOI:
10.14359/9668
Date:
11/1/1995
Abstract:
Structural walls are used extensively in low- and moderate-rise buildings to resist lateral loads induced by earthquakes? The seismic performance of many buildings is, therefore, closely linked to the behavior of the reinforced concrete walls. The potential hazard of a shear failure of a structural wall during an earthquake has been documented by the results of laboratory tests.2-6 Walls display pinched hysteresis curves and poor energy dissipation characteristics, experience stiffness degradation with cycling, and may exhibit a sudden loss in lateral load capacity due to web crushing. Nevertheless, most design procedures for structural walls ignore these key aspects of the cyclic response. The analytical models used in this paper were developed specifically to study the cyclic response of reinforced concrete walls, 7 and may be used to investigate the influence of a range of structural parameters on laterally loaded walls. The models were validated by comparing the calculated response with the measured response of 13 walls tested at the Portland Cement Association in the 1970s. Additionat analyses were performed to determine the influence of web reinforcement on the hysteretic response of structural walls. Emphasis is placed on selecting web reinforcement to minimize the likelihood of shear failure. Finite element models are used to study the behavior of slender reinforced concrete walls subjected to lateral load reversals. Nonlinear material models for concrete and reinforcing steel that are capable of reproducing the salient features of hysteretic wall response are discussed. The results of the finite element analyses are compared with measured data from several experimental programs to verify the models. Examples of walls with and without openings in the web are presented to demonstrate the influence of web reinforcement on the cyclic response of walls. Diagonal reinforcement in the web is identified as an eficient means of limiting shear distortion, increasing energy dissipation, and reducing the likelihood of shear failures in structural walls.