TORSIONAL CAPACITIES OF CAP BEAMS IN ELEVATED TRANSPORTATION STRUCTURES
This paper investigates the torsional load capacities of two reinforced concrete cap beams in the elevated guideway structures. One beam has a regular configuration and the other has an irregular configuration. For each beam type, a 1/2-scale model was tested. The failure mechanisms of both beams were dominated by torsion. The load capacity of the regular beam was governed by the yielding of the main longitudinal reinforcement induced by a truss action. The capacity of the irregular beam was governed by a torsional crack through the columns zone, which can be attributed to the lack of confinement in the region. The large spacing of the top horizontal ties in the regular beam led to vertical splitting cracks when the beam was loaded through the shear keys. Nonlinear finite element analyses have been conducted on the beams. The finite element models are able to reproduce the nonlinear behaviors observed in the tests with reasonably good accuracy. Based on the experimental observations and numerical results, strut-&-tie models have been developed to evaluate the load capacities of the beams. Both types of models have indicated that the horizontal load resistance of a cap beam under bending and torsion will decrease with the decrease of the vertical load.
Bent caps reinforced concrete beams finite element method strut-&-tie model torsion earthquake performance
P. Benson Shing Minho Kwon Chip Mallare Jose Restrepo
Professor, Dept. of Structural Engineering, University of California at San Diego, La Jolla, CA 9209 Assistant Professor, Dept. of Civil Engineering, Engineering Research Institute, Gyeongsang National HNTB, 1330 Broadway, Suite 1630, Oakland, CA 94612
国际会议
14th World Conference on Earthquake Engineering(第十四届国际地震工程会议)
北京
英文
2008-10-12（万方平台首次上网日期，不代表论文的发表时间）