Analysis of shear stress of single-box double-cell variable cross-section composite box beams with corrugated steel web
To study the shear stress distribution of single-box double-cell variable cross-section composite box beams with corrugated steel web(CBBCSW),the problem that the top,bottom and corrugated steel web(CSW)of the single-box double-cell variable cross-section CBBCSW participate in shear was analyzed.The formula for calculating shear stress of CSW with variable cross section was derived by using the equilibrium of infinitesimal element and the reciprocal theorem of shear stress,and compared with shear stress calculation formula of CSW with uniform cross section.The properties of various shear stress were studied,and the top and bottom plates of variable cross-section CBBCSW and the mechanism of participating in shear bearing were analyzed.The formula for calculating the bearing-shear ratio of the bottom plate was proposed.Taking the model test beam and a single-box double-cell variable cross-section CBBCSW as examples,the finite element(FE)models of the test beam and the bridge model were developed by using ANSYS.The distribution of shear stress on CSW under different restraint systems and the law of top,bottom and CSW participating in shear were studied.The difference between the finite element calculation results and the theoretical formula calculation results under different load conditions was compared.The influence of different load conditions on the participation of the top,bottom and CSW in shear was analyzed.In addition,the effect of the diaphragm on the distribution of shear force was analyzed.The results show that the theoretical results of the proposed formula are in good agreement with the test results and FE results.The proportion of the bottom plates participating in the shear bearing cannot be ignored.The"additional shear stress"caused by variable cross-section is the direct reason that affects shear force transmission.The size of bending moment will directly affect the proportion of bottom plate participating in shear bearing.Under symmetrical load,the shear force distribution of middle web and side web is almost the same,while the diaphragm will change the shear force distribution on CSW,and the shear stress distribution near the diaphragm will be more uniform.The research conclusions can provide reference for the analysis of shear stress and bearing-shear ratio of variable cross-section CSW.
composite box girdercorrugated steel webvariable cross-sectionshear stressshear ratiofinite element analysis
万方数据
维普
