Numerical Simulation And Protection Technology Of Rolling Stones Collision

With the rapid growth of China's national economy and the transportation industry,more and more bridge structure appear.At the same time,accompanied with the development of the western,highway construction in Mountainous Areas develop so much.Due to the complex topography in the mountainous area and the structures of the expressway,in the new construction of highway,the length of bridge and tunnel accounts for a large proportion.Moreover,The pier of bridge is built in double column piers or hollow thin-walled pier to reduce the amount of material and the weight of pier of bridge.But this kind of bridge pier is poor in resistant impact from outside,especially facing the problem of rolling the impact of flash floods in the western region.In order to improve the anti impact ability of the montanic bridge,to ensure the safety of the bridge during operation,this article is based on a hollow thin-walled pier bridge in Jiangxi,and analyses dynamic process when the rolling stone impacts pier and several main factors of influence impact force in analogy method;Besides,the article puts forward a kind of device for anti-collision of the pier,and analyzes the capability of the device.This article establishes the model of the rolling stones,the pier and the anti-collision device in the whole collision process by finite element analysis software patran/ls-dyna,The main research work of this dissertation are as followed:(1)Through simulation analysis and numerical method,establish the model that the rolling stone bumps the pier,obtain the curves of collision force and energy curve.(2)Analyze the factors that influence the impact force,establish the impact model in different speed,quality,shape,angle and so on,to calculate the empirical formula which could calculate impact force.(3)Analyze when the rolling stones impacts the pier,the stimulant progress that the bridge continuously collapses.(4)Compute the resistance of pier structure to provide a theoretical reference for the establishment of the anti-collision facilities for pier.(5)Compare with different anti-collision materials,and put forward reliable anti-collision facilities and a collision avoidance model.(6)Establish the finite element model of rolling stone,anti-collision facilities,and bridge piers.Compare the distribution of stress before adding pier anti-collision facilities with it after that,and analyze the distribution of stress of the anti-collision facilities,then demonstrate the reliability of the anti-collision device.At last,this article discusses the research area about impact of the rolling stone,and summarize some results and further study.