Applied Mechanics and Materials Vols. 178-181

Abstract: This paper presents theoretical and finite element investigations on inelastic displacement of assembled truss bridge with cable reinforcement (hereinafter referred to as ATCR). A method based on the Principle of virtual work for the determination of the inelastic displacement of ATCR is proposed. Finite element analysis was conducted on the specimen models using the ANSYS program, in order to obtain the inelastic displacement of ATCR and to compare with theoretical results. This study focuses on Bailey bridge under the self-weight load and prestressing force on cable. This paper analyzes various specimens to obtain inelastic displacement in different cases. The approximations of a relation between the inelastic displacement and prestressing force on cable are found. It can be seen that the method in this paper can both calculate the inelastic displacement of traditional truss and prestressed truss (ATCR). Based on both the theoretical and the finite element results, it can be concluded that the relation curve between inelastic displacement and prestressing force is stepwise.

Abstract: An important part of system reliability estimation is to identify the subset of significant failure modes. A new identification method was proposed for the combination of failure modes of a concrete filled steel tubular arch bridge. The innovative method was based on critical strength branch and bound algorithm and implemented in the combination with the finite element package ANSYS and the MATLAB procedure. The results reveal various combinations of failure modes in significantly reduced time and efforts comparing to the previous conventional method. Additionally, the suggested method can be used for the verification of the system reliability with more specific predictions of the failure mode.

Abstract: Through the measured simply supported bridge's dynamic parameters, we can establish the finite element model of the structure.As the flexibility matrix can reflect the actual state of the bridge, making the actual measured flexibility matrix as a basis to inverse the bridge’s finite element model .Combined with the engineering practice static load test, we can assess the bearing capacity of the bridge according to inversion model bridge.

Abstract: As a result of the path route and the width change and in order to connect south of K4 + 726.852 bridge with road in HengZhou avenue smoothly, we need to reverse the cross slope which takes up 2 percent of the bridge deck. We analyze three different reform plans, so as to ensure security of HengZhou bridge. Firstly, we compare the influences for the bridge structure bearing capacity from different projects. Secondly, we study the transformed force performance. Thirdly, we evaluate the bearing capacity. Result shows that transformation surfacing method is costless and easy to operate. The bearing capacity meet the requirements after the transformation. The research achievement has some reference value to other similar bridge for strengthening

Abstract: The cable-stayed bridge is a type of the bridges that can utilize the material properties fully and rationally.They are most favored by designers both at home and abroad with its good economic performance and crossover capability. we use the method of the minimal stress with constraints to optimize the cable force of the completed bridge under dead loads. In this way, we can attain the goal of reducing the project cost.

Abstract: A method of prefabricating beam on bridge floor is sometimes employed in mountain difficult terrain. Four forms of longitudinal pedestal layout and three analysis cases obtained by orthogonal analysis method were drawn up, the mechanical behavior of the tool girder were studied by the finite element software and the role of deck pavement for tool girder was discussed. The results show that when the end of pedestal was situated in mid-span, the tool girder will reach the most disadvantageous status. Moreover, reinforced concrete deck pavement not only can improve the stiffness and integrity of the tool girder, but also can effectively decrease internal forces and deformations of the tool girder.

Abstract: Clad plates welding of stainless steel welding on interlayer between grass roots and the transition layer is a key technology.Structure and properties of welded joints is very uneven,and there have often welding repair cracks. Clad plates of stainless steel material is used to weld under construction in the Southern link’s railway bridge for the first time at home .However, there occurs welding warpage of the convex parts and roughness appears excessive on the overall clad plates and severe deformation, and the quality of railway bridge is affected seriously. Reasons of the impacting welding quality are analyzed and specific measures to control them are proposed and the construction program is optimized.the efficiency and quality of welding can be improved ,a good foundation for the compound plates welding is layed,it will be contribute to ensure the overall quality of the welding quality of railway bridge especially the use of clad plates.

Abstract: Initial damage often exists in the concrete piers of bridges in service. In this paper numerical analysis was used to study the seismic strengthening behavior of concrete bridge piers with different bending damage degrees, including seismic forces, pier top displacements, steel bar strain and energy dissipation, in order to obtain the strengthening demand to repair the damage piers. The results showing that: initial bending damage reduced the seismic force, increased the pier top displacements and the steel bar strain. After strengthening the pier top displacements and steel bar strain at the pier bottom decreased, energy dissipation increased, and the anti-seismic properties of damage piers effectively recovered, but the increase of the seismic force might make new plastic-hinges out the strengthened area. At last according to the mechanics properties the strengthening demand under different bending damage degrees was given.

Abstract: Bridge structure is influenced by external temperature inevitably, and hyper static structure, especially cable-stayed bridge, has complicated stress response on the effect of temperature action, which greatly increases the difficulty of structure stress analysis. For the sake of research on the influence degree of temperature action to large span concrete cable-stayed bridge girder, take Luzhou Taian Yangtze River Bridge as an example, the temperature field and temperature stress of girder are analyzed using measured data from health monitoring system. The results of finite element simulation experiment demonstrate that, the influence of longitudinal temperature distribution must be considered in large span bridge design, and the measured data of bridge health monitoring system installed are accurate.

Abstract: In the premise of structural parameters of not changing, cable-stayed bridge state by taking the reasonable force will become the optimization of cable-stayed bridge under constant load by taking the reasonable under the bridge state superpositioning optimization problem. Basing on the engineering background of Dachongyong bridge with finite element analysis software of Midas/Civil, taking the unknown load coefficient method of Midas/Civil as study platform, arounding the theme of the reasonable state of cable-stayed bridge, This paper make full use of the characteristic of cable forces can be adjust, introduced the method of superpositioning optimization algorithm in detail under the reasonable cable-stayed bridge state.