Sutdy On Isolation Performance Of Single-layer Cylindrical Latticed Shell Based On Tiss

In recent decades,the latticed shell structure applied to the large-span spatial structure has developed rapidly both in the domestic and overseas with its reasonable mechanical characteristics and beautiful structural shape.However,in 2013,most of the latticed shell structures have been seriously damaged by earthquake occurred in Lushan,which triggered a hot topic for searching the performance of long-span spatial structures under seismic action.At present,the seismic performance of most long-span space structures can not fully resist the strong earthquake.Therefore,it is urgent to put forward some improvement measures to improve the seismic performance of space structures.Based on the three dimensional isolation spring support(TISS),this paper proposes three types of isolation systems for single-layer cylindrical latticed shell structure,which are base isolation system,column top isolation system and double isolation system.In order to compare and analyze the isolation performance of single-layer cylindrical latticed shell with various isolation systems,the shaking table test and finite element analysis have been carried out.The result shows that the response characteristics and laws of each system under different design parameters are obtained.The main contents and achievements of this paper are as follows:(1)Analysis of test data of isolated single-layer cylindrical latticed shellThe data from tests for the scale model of single-layer cylindrical latticed shell structure on seismic simulation shaking table with base isolation system,column top isolation system and double isolation system are compared and analyzed respectively,and the response characteristics and rules of measuring points are obtained.By comparing the response parameters from the scale model under the three isolation systems,it is found that isolation effect of the double isolation system performs better than the base isolation system and the column top isolation system which are basically the same.(2)Numerical simulation of test model based on ABAQUSThe refined finite element model for single-layer cylindrical latticed shell has been established by ABAQUS,and the reasonable simulation method of bearing limit element has been proposed.The modal parameters and response time history curves under the three systems(the top isolation,base isolation and double isolation)have been obtained by numerical simulation method.By comparing and analyzing between the measured value and the simulated value with the finite element,it is found that the three finite element models under isolation system with the parameters can perform well on simulation,which proves that the proposed simulation method of single-layer cylindrical latticed shell considering the TISS effect is reasonable,and can simulate the shaking table test well.(3)Analysis of isolation performance of single-layer cylindrical latticed shell considering the action of TISSFor the actual single-layer cylindrical latticed shell structure,the finite element parameter analysis of the column top isolation,foundation isolation and double isolation system has been carried out and the isolation performance has been compared respectively to determine the optimal isolation system.Meanwhile,the effect rules of the structural parameters(frame stiffness,frame height and rise span ratio of latticed shell)on the isolation performance of single-layer cylindrical latticed shell structure is explored.It is found that with the increase of seismic energy,the isolation performance of TISS bearing increases gradually,and it remains stable after reaching a certain degree,and has the optimal isolation effect in the double isolation system.Moreover,TISS supports perform well on adaptability to the structural parameters of the latticed shell.