The Finite Element Analysis Of Cable-Steel-Reinforced Concrete Structure

The passenger foot-bridge(also names overpass,footpath bridge)is the important component in the urban road projects,which is built in the transportation-crowded area between the buildings aside the street as the crossing-street bridge to help the passer-by cross street safely and to satisfy the demands of the person and vehicle divergence[1].The passenger foot-bridge and the pedestrian tunnel have become two main ways to solve the pedestrian to cross street in the urban road transportation.This project's example comes from the overpass between the crested ibis center and the Watanabe Shipyard in the Japanese Niigata county which was collapsed just after completing and not yet in the operational period.This overpass,containing five spans,respectively 30m, 36m,36m,48m and 36m,has broken down in the 48m-span.Bearing piles and over-bridge pedestrian deck is made of reinforced concrete and over-bridge sealed corridor as well as columns and crown vertical beams,crossbeams of molding steel.The composite truss, comprised by reinforced concrete deck and the steel columns,has designed the diagonal pre-stress cables between the most longitudinal internodes.This article takes the finite element theory as a foundation and collapsed 48m-span as the background to establish the finite element model,with the nonlinear module of the general finite element software ANSYS to make the simulation analysis.The prime tasks are as follows: (1)to explore the shape of the slanting cables with the software ANSYS's life and death unit law and APDL;(2)to calculate respectively the structure's inner force and distortion under the conditions as follows:â‘ self-weight + zero live load,â‘¡self-weight + full-span live load,â‘¢self-weight + left half-span live load,â‘£self-weight + right half-span live load;(3)to obtain the structure's various steps base frequency as well as the structure's various main steps modality characteristics by the modal analysis;(4)aiming at steel rate most province,to optimize the structure according to related standards with software ANSYS APDL,to discuss what the different rope diameter can make influences to optimized results and to provide the references for this kind of related designs.This research of the article can strengthen understanding of the stress characteristic as well as the stress mechanisms to the combined steel truss and the slanting structure bridge. Also,the conclusions will have the important reference value to the related engineering designs.