Study On Residual Shear Strength Of Reinforced Concrete Bridge Columns Under Strong Seismic Ground Movement

Under strong seismic ground movement, after the reinforced concrete bridge columns undergo inelastic deformations, the section happened serious failures and seismic shear strength and stiffness degrade rapidly. Furthermore the predictive equation for shear strength proposed by the current design code for highway bridges is suitable for state loads, but not for seismic loads. For the purpose of solving the problem, this paper focuses on the residual shear strength of reinforced concrete bridge columns. The main contents of the paper are describes as follows:a. The progress on the relevant research in home and abroad is systematically reviewed firstly. Summarizing the research results on theory and test, and made draw conclusions from them. And introduce the main theory of resisting shear.b. Based on the qualitative analysis on the factors affecting the residual shear strength and refer to the current codes, the concrete component is revised by adopting truss-arch mode. Based on a regress analysis of the results of 74 columns models from eight different tests, an empirical formula for calculating the residual shear strength of reinforced concrete bridge columns is derived. And compare the formula to them proposed by the current codes. The results shows that the formula is more access to the matter of facts, and the scatter is more little.c. Test performed through 8 reinforced concrete bridge columns models under cyclic loads. And the results indicated the effects of axial load ratio and ductility to the residual shear strength. The test's results affirmed the accuracy of the empirical formula.