Dynamic Analysis Of Slope Supported With Frame-anchors Under Earthquake Action

Supporting structure with frame-anchors with the development of supporting structure made of a new type of supporting structure. Because the structure can effectively control the displacement of the slope, and can be combined with some greening measures, therefore, the structure has been developed rapidly in the road and rail slope. In addition, the supporting structure has certain seismic performance because the flexible structure can allow a certain deformation.But at present both at home and abroad, the study of seismic performance and dynamic problems are still very lack.During the 5.12 earthquake, the slope with thus supporting structure has demonstrated good seismic performance.Supporting structure with frame-anchors as a new type of retaining structures, has played a significant role in the process of western development.It has great realistic meaning in the new national policy of stimulating domestic demand,with further development about seismic analysis and design research of flexible retaining wall.This paper carried out a research based on the study about dynamic analysis and the seismic design method of the slope with frame-anchors,and put forward some new ideas and calculations, research work are as follows:According to the mechanism of supporting system with frame-anchors, analysis model is divided into two steps of dynamic soil pressure model and dynamic frame-anchors supporting structures model. Firstly,consider the effects of slope height on seismic soil pressure distribution. When earthquake happens, the soil pressure act on the supporting structures was supposed to distribute as inverse triangles. The maximum pressure was on the top of the wall and decreased gradually downwards. Secondly, based on lumped masses model developed by Penzien, the frame structure analysis model was constructed with a set of lumped masses. Frame structure and soil was connected by anchors with spring supports. Taking the columns of frame as calculating unit, the corresponding control equation of dynamic model was established. Through the analysis of vibration mode, vibration equation was developed and vibration mode reaction was solved. Based on the solution of dynamic soil pressure and the analysis of vibration model response, support reaction of each node can be obtained. The result of dynamic soil pressure and vibration model responss can provide reference for the seismic design of supporting system with frame-anchors.Finally, through an engineering example, with the previous results of FEA software ADINA, this calculation model was verified.The results show that the computational model is feasible to the dynamic design and analysis about soil slope which is more uniform.