Dynamic Response And Safety Evaluation Of Concrete-Filled Steel Tube Tied Arch Bridge Under Explosion

Due to the advantages of rational force statement,beautiful appearance and strong adaptability to the foundation,the concrete-filled steel-concrete-concrete truss arches are heavily constructed.In recent years,there have been many incidents involving the explosion of cars carrying flammable and explosive materials and car bomb attacks,causing serious damage to the bridge structure.In this paper,through finite element modeling analysis,the research work on the dynamic response and the safety evaluation of the Concrete-Filled Steel Tube Tied Arch Bridge subjected to explosion.The specific research content is as follows:1.According to the research on the propagation law of blast wave and the interaction between explosion shock wave and structure by scholars at home and abroad,comparing the current methods of simulated blasting and explosive interactions with structures,and obtained the more accurate and mature method for simulating explosion effect and interaction between explosion effect and structure.2.According to the mechanical properties of air,concrete and steel under explosives,drawing on the finite element modeling method and finite element model grid division of the various components of tied arch bridge,finite Element simulation method of tied arch bridge subjected to explosive impact is determined.Explosion-structure interaction method and various material parameters verified by the existing explosion test results.3.Taking a tie-bar arch bridge as the research object,the finite element modeling method was used to analyze the dynamic response of each member of the tied-arch bridge under various operating conditions,and the damage scope and the most unfavorable cross-section of the tie-arch bridge were obtained by analysis the dynamic response of the bridge subjected to explosion.4.Based on the stress,strain response and damage degree of each component of the tied arch bridge under the explosion,a safety evaluation method for the bridge components under the explosion is established.Combining the specification of bridge technology Status and the characteristics of bridges of tied arch bridges,a safety assessment method for tie arch bridges structural system is established.