Static test and effective pre-stress analysis of composite trough girder with corrugated steel webs
Chen Zhuoyi1 Huang Qiao2 Li Chuanxi1 Yang Ming2 He Jun1
1. Key Laboratory of Department of Education and Hunan Province, Changsha University of Science & Technology, Changsha 410114, China;
2. Southeast University, Nanjing 210096, China
Abstract：Composite trough girder with corrugated steel web (TGCW) is a new type of through bridge with open thin-walled members. 4 scaled TGCWs with the similarity ratio of 1:4 were tested by two-point symmetric loading and analyzed by the finite element method. The loading-displacement relationship, section strain distribution, cracking development law and failure shape of the 2 group beams are studied. The effective compressive pre-stresses of test beams in bottom slabs were analyzed after the pre-stress were imposed and the pre-bending forces were released. The research results show that the test beams conform to the law of plane section deformation under vertical loads, the flexural rigidity of corrugated steel webs and the flexural resistance of concrete bottom slab can be ignored. The strain distribution of the test beams in compressive zone are trapezoid instead of conventional triangle due to the area limit of top flanges. The neutral axis of trough girders are low, the compressive pre-stress can be imposed to the concrete effectively after rebounding of the reflexed corrugated steel girders, and the corrugated steel webs can enhance the applied effective pre-stress of trough girders. By the proposed pre-stress equivalent load method for composite corrugated steel webs girders, the effective concrete pre-stress can be accurately calculated. Two failure modes for the two group of test beams are plastic and brittle bending failures, respectively, according to the quantity of reinforcement. The concrete cracks extend thorough the bottom slab, and the top flange concrete break to pieces at last. The TGCW is light-weight with great flexural rigidity, good ductility and cracking resistance.
