Mechanical Safety Performance Analysis Of Half-through CFST Archbridge In The Demolition Stage

In this paper, combined with the demolition of Yilan-Mudanjiang Bridge, demolition method, construction control and the stress performance of half-through CFST arch bridge are studied.Yilan-Mudanjiang Bridge needs to be demolished and rebuild because it’s performance cannot meet the requirement. This paper start with the two mainstream method-explosion demolition and mechanical demolition, according to the mechanical characteristics, dismantle requirements and environmental restrictions of Yilan-Mudanjiang Bridge itself, eventually determine the demolishing project. Then according to the project, use the space finite element software Midas/Civil to simulate the demolition process, analyze the influence of temperature and wind load on the structure, meanwhile analyze the regularity of the arch rib s deformation and stress, the rotation of the arch springing and the horizontal thrust of the pier.In order to guarantee the construction smooth and safe, establishing completed construction control system according to the project, measure the actual temperature and wind speed to adjust the model, then determine the threshold of deformation and stress during the demolition, compare the actual monitoring data with the theoretical data, constitute a warning system to make the demolition process smooth. At last, make analysis on the mechanical safety performance of the main stress components in demolition—arch rib, come to the conclusion that the arch rib is under control during the whole stage.Through the study, we should select suitable construction method and process according to different engineering practice, consider the natural factors may influence the structure, then use finite element software to make simulation and analysis in the construction process can provide advice. The research of this article has a certain reference value in the similar demolition.