Research On The Road Construction Exerts Influences On Nearby High-speed Bridge Pier Displacement

With the expansion of China's high-speed railway and highway construction,density of road network,the roads and high-speed railway at all levels inevitably exist in parallel and cross due to the lag of planning,the existence of equation of time,economic conditions and land resources constraints and other factors.Near road construction will inevitably impact on high-speed railway bridges.Depending on the practical engineering problem of the parallel construction of high speed rail for a municipal road project,a three-dimensional finite element analysis model was established based on the pier and pile foundation of the high speed railway bridge,and the changes of the height,depth and bearing capacity of the subgrade,as well as the displacement of the high speed rail bridge pier and abutment were studied.Based on the results of theoretical calculation and numerical simulation,the distance between near road construction and close to high speed rail bridge,the width and height of the subgrade and the proposed bearing capacity of the foundation were proposed.The main research contents are as follows:(1)Based on the site of the bridge road project near the high speed rail,the influence of construction on the displacement of pier and abutment was summarized on the basis of extensive investigation and investigation of relevant documents and materials at home and abroad.(2)On the basis of the finite element model,the influence of the new road embankment on the existing high-speed railway bridge was studied.The effect of the height of the embankment,the depth of the cutting,the embankment filling,the cutting width,the distance between the existing bridge and the bearing capacity of the existing bridge and the bearing capacity of the foundation on the existing high-speed railway bridge was analyzed in detail.The horizontal displacement and settlement of bridge were compared with the relevant norm limits.(3)The safety evaluation of high-speed railway bridge was carried out through taking reality engineering as a case.According to the results of theoretical calculation and numerical simulation,the distance between near road construction and high speed railway bridge,the width of subgrade and the recommended value of foundation bearing capacity were proposed,and the corresponding construction suggestions were put forward.