High-speed Railway To Move The End Of The Tunnel Under The Load Dynamic Characteristics Of Experimental Research

With the great increase of train running velocity, the structural vibration of the tunnel bottom also increases. Under the condition that the slab track is used, the train vibration responses is enlarged and damage deformation of the bedrock occurs, this can cause the deformation of the bottom structure and tracks, therefore, the operation safety of the high speed train will be greatly influenced. Such problem is studied in this thesis, by the means of the model experiment, the characteristic of structure dynamic response under the high speed train load is analyzed. The main work of this paper is as follows:(1)Through a detailed investigation of a large quantity of related literature, a proper research aim is made on the basis that the problems which exist in the study of structure dynamic response under the high speed train load are well studied.(2)Based on related research achievements, and after several important steps(chosen of the experimental material,installation of the experimental device and arrangement of the measuring instrument), the ratio for the geometric similarity is determined to be 1/4, and ratio for the elasticity modulus similarity is 1/2, these results are derived from the similarity theory.(3)After considering a lot of kinds of experimental materials, finally the soil cement is chosen to simulate the bottom bedrock, and microconcrete materials is used to simulate other concrete members; before the model is made similar materials are tested to determine the material characteristics.(4)Servo vibration generator MTS is applied to simulate the train load, and the structural dynamic tests are taken under the velocity of 200km/h,250km/h,300km/h, all the results reveal the interaction relationship between the tunnel bottom and the bedrock,the law of the vibration travelling,the influence basin and degree of the vibration wave travelling in the bedrock.