ABSTRACT
In recent years, with the development of urban traffic and the increasing attention to the bridge landscape and aesthetics around the world, ultra-wide steel box girder self-anchored suspension bridges are widely used in urban bridge construction due to their exquisite shape and lightweight configuration. The structural form is complicated under stress, and under heavy vehicle loads, local stress is too powerful and the service life of the bridge is badly affected. To probe into the actual stress of the self-anchored suspension bridge with the extra-wide steel girder under vehicle loads, this paper traverses the stress distribution rule, deformation and failure mechanism of the cable tower and the ultra-wide steel box girder under different vehicle loads. Meanwhile, the stress of the main cable and the suspender are investigated. Based on the multi-scale finite element model of ANSYS, the paper also relies on the load test results of the self-anchored suspension bridge with the extra-wide steel girder. The results show that: (1) The numerical simulation is consistent with the results of the field load test. (2) The longitudinal tower displacement of the main tower under the design load is more obvious than that of the transverse bridge. (3) The girder is affected by the shear lag effect, and the local effect of the roof is obvious. (4) The stress increased near the top plate at the web is significantly larger than that at the web. (5) Negative shear lag occurs at the intersection of the longitudinal beams. (6) The torsional deformation of the girder is obvious under eccentric load. (7) The stress value of the U rib of the top plate is too high, and the alternating stress occurs at the lower edge. (8) Under the action of eccentric load, the main cable and the boom are not evenly stressed. The research results can provide a certain reference for bridge design and maintenance.
