Study On The Torsional Effect And Experiment Of Isolation Structures On The Slope

The economic and social development in the western region has resulted in the reduction of the floor area,the location of the building site turns to the slope,and then the form of structures on the lope comes out.The structure of horizontal and vertical stiffness are not continuity,which is easy to torsion effect under the action of earthquake.To reduce torsion of the structure,the author propose the form of isolation structures on the lope.The paper are three aspects of the indepth study on the torsional effect of the structure,as from theory,experiment and finite element simulation,The main contents and conclusions are following:(1)Isolation technology has wide application range,reduce the earthquake disaster characteristics obviously.The author put forward the concept of isolation structures on the lope and four major isolation structure,according to different conditions of mountain landscape,forming a preliminary system of isolation structures on the lope.(2)To select the isolation structures on the lope as the research object in this paper.Base on layer frame isolated structure as rigid torsion theory model and the characteristics of mountain seismic frame structure,the author focus on isolation structures on the lope response factors,dynamic torsion rule and control index analyzed of torsion,and choose of isolation layer eccentricity,different ground motion as the research direction of input parameters in this paper.Base on research status of isolation structure with complex irregular,to select shaking table test method,and design the corresponding test model.(3)The isolation structures on the lope of shaking table test,four test conditions were designed.The test results show that the isolation torsional dynamic response of structure reduce obviously.On ground layer and the top layer is the weak part of the structure.The seismic input of cross slope,eccentricity of up isolation layer,two isolation layer on the same side eccentricity are the main influencing factor.When the eccentricity of upper and lower isolation layer less than 5%,the structure of the torsional response can meet the maximum specification requirements.The relative torsional effect can be used to determine the value of structural torsion index.The model of original structure test prototype value and experimental value error is small,the finite element model can be used as an effective model for extended research.(4)Using ETABS software to carry out parametric analysis of original structure,expand test conditions of four different eccentric eccentricity range and direction.The results of the study show that,in addition to the test conclusion of the three factors of isolated structure torsion,and p eccentricity of the cross slope is the main factors influencing the structure of eccentric torsion.The relative torsion effect value can also be used to determine the structure still torsional index.(5)Add friction and energy dissipation dampers to the two up and down isolation layer.And to select the same test condition of the base isolation structure,to make supplementary comparative experimental research.The test results show that the dampers can further reduce the torsion effect of isolation structures on the lope.