Integral Analysis Of Grid Roof Isolation Effect For Gymnasium Building

At present,base isolation is more common.If the base isolation technology is applied to gymnasium buildings,the grid structure is often adopted in large span structure.There is a point support connection between the top of the column and the roof of the large span.Both ends are hinged,so the lateral lateral stiffness of the structure is greatly reduced.When subjected to loads such as earthquakes or wind loads,the lateral displacement of the structure will increase,and for a single-layer open structure,it is often difficult to form a complete isolation layer between the foundation and the top of the column.Therefore,a method of changing the grid support of the frame structure of the frame with the frame to the isolation bearing for isolation is generated.However,compared with the foundation isolation technology,the roof isolation technology of the grid roof is still not mature,and there are still many problems in engineering applications.In this paper,the feasibility of roof isolation design for the mixed structure of gymnasium with grid is studied.In this paper,three typical grid roof and gymnasium hybrid structures are selected,and the roof isolation model is established.The finite element software SAP2000 is used to analyze the dynamic elasto-plastic time history of the fortification earthquake and rare earthquakes.By comparing before and after the isolation of the Grid member axial force,grid span deflection,interlayer shear and plastic hinge development of the overall structure and distribution to judge the whole of the structure vibration isolation effect.Study on the effect of the grid support on the seismic performance of the overall structure after changing the support of the rubber frame.The specific research content is as follows:(1)The finite element simulation of the isolation structure of three typical gymnasium roofs is carried out.The upper frame axial force,the lower frame layer shear,the interlayer displacement angle,etc.of the structure before and after the earthquake isolation and rare earthquake are compared and analyzed.Change the situation and explore its isolation effect.The results show that the isolation effect of the upper frame of the isolation structure of the three gymnasium roofs is significant,but the isolation effect of the lower frame of the isolation structure of the single-story open-story and single-story open-story frame gymnasium roof is better than that.The layered gymnasium roof is isolated,and the base shear force and interlayer displacement angle are reduced by 30%~50%.(2)Aiming at the building isolation structure of multi-story gymnasium,the dynamic elasto-plastic time history analysis was carried out under the earthquake and rare earthquake,and the isolation effect was explored.At the same time,by comparing the seismic response of the roof isolation structure and the base isolation structure,the advantages and disadvantages of the two isolation technologies are compared and compared.The results show that the overall isolation effect of the base isolation structure is significant,but the isolation effect of the upper grid is weaker than the roof isolation.The axial force of the upper chord decreases by 7%~30%;The difference between abdominal axial force amplitudes is 5%~20%,but the isolation effect of the lower frame is better than that of the roof isolation.The reduction between the interlayer shear force and the interlayer displacement angle is about 50%.(3)The distribution of the overall plastic hinge development of the three typical gymnasium roof isolation structures under rare earthquakes is analyzed.The yield state of the upper and lower frame members after roof isolation is analyzed,and the three roof isolation structures are analyzed.At the same time,the basic isolation structure of the multi-layer gymnasium is analyzed,and the yielding state of the whole structural members of the roof isolation model is compared with the strength of the two isolation schemes.Results show that the three kinds of typical rain playground roof structure grids are in elastic state,the top of the monolayer hollowness and single-layer affiliated with open framework rain playground roof structure of bottom framework components and plastic damage situation is better than that of multilayer rain playground roof isolation,multilayer rain playground roof structure of bottom framework underlying individual longitudinal side column to yield.The upper grid of the multi-layer gymnasium base isolation structure and the roof isolation structure are in an elastic state,and the lower frame of the multi-layer wind and rain roof isolation structure has more yielding members than the base isolation.In general,the plastic damage of the base isolation structure of the multi-layer gymnasium is better than the roof isolation structure.