The synergistic use of partially encased concrete and composite girders with corrugated steel webs （CGCSWs） has been proposed to avoid the buckling of corrugated steel webs and compression steel flanges under large ...The synergistic use of partially encased concrete and composite girders with corrugated steel webs （CGCSWs） has been proposed to avoid the buckling of corrugated steel webs and compression steel flanges under large combined shear force and bending moment in the hogging area. First, model tests were carried out on two specimens with different shear spans to investigate the mechanical behavior, including the load-carrying capacity, failure modes, flexural and shear stress distribution, and development of concrete cracking. Experimental results show that the interaction of shear force and bending moment causes the failure of specimens. The bending-to-shear ratio does not affect the shear stiffness of a composite girder in the elastic stage when concrete cracking does not exist, but significantly influ- ences the shear stiffness after concrete cracking. In addition, composite sections in the elastic stage sat- isfy the assumption of the plane section under combined shear force and bending moment. However, after concrete cracking in the tension field, the normal stresses of a corrugated web in the tension area become small due to the ＂accordion effect,＂ with almost zero stress at the flat panels but recognizable stress at the inclined panels. Second, three-dimensional finite-element （FE） models considering material and geometric nonlinearity were built and validated by experiments, and parametric analyses were conducted on composite girders with different lengths and heights to determine their load-carrying capacity when subjected to combined loads. Finally, an interaction formula with respect to shear and flexural strength is offered on the basis of experimental and numerical results in order to evaluate the load- carrying capacity of such composite structures, thereby providing a reference for the design of partially encased composite girders with corrugated steel webs （PECGCSWs） under combined flexural and shear loads.展开更多
基金The authors gratefully thank the National Natural Science Foundation of China （51308070, 51408070, and 51378080）, the National Basic Research Program of China （2015CB057702）, the Key Discipline Fund of Creative Project of Bridge and Tunnel Engineering （13ZDXK04） from the Changsha University of Science and Technology, the Open Fund of the Hunan Province University Key Laboratory of Bridge Engineering （13KA04）, and the Applied Basic Research Program of Shanxi Province for their support,
文摘The synergistic use of partially encased concrete and composite girders with corrugated steel webs （CGCSWs） has been proposed to avoid the buckling of corrugated steel webs and compression steel flanges under large combined shear force and bending moment in the hogging area. First, model tests were carried out on two specimens with different shear spans to investigate the mechanical behavior, including the load-carrying capacity, failure modes, flexural and shear stress distribution, and development of concrete cracking. Experimental results show that the interaction of shear force and bending moment causes the failure of specimens. The bending-to-shear ratio does not affect the shear stiffness of a composite girder in the elastic stage when concrete cracking does not exist, but significantly influ- ences the shear stiffness after concrete cracking. In addition, composite sections in the elastic stage sat- isfy the assumption of the plane section under combined shear force and bending moment. However, after concrete cracking in the tension field, the normal stresses of a corrugated web in the tension area become small due to the ＂accordion effect,＂ with almost zero stress at the flat panels but recognizable stress at the inclined panels. Second, three-dimensional finite-element （FE） models considering material and geometric nonlinearity were built and validated by experiments, and parametric analyses were conducted on composite girders with different lengths and heights to determine their load-carrying capacity when subjected to combined loads. Finally, an interaction formula with respect to shear and flexural strength is offered on the basis of experimental and numerical results in order to evaluate the load- carrying capacity of such composite structures, thereby providing a reference for the design of partially encased composite girders with corrugated steel webs （PECGCSWs） under combined flexural and shear loads.
