Analysis Of Seismic Performance Of An Over-limit Structure With Sliding Bearings

It is an efficient and economical practice to install sliding bearings in buildings to improve the seismic performance of the building structure.For buildings with irregular vertical stiffness,in order to meet the requirements of building codes,seismic isolation bearings can also be installed between the layers in order to meet the requirements of the specification.For building structures with seismic isolation bearings,it is difficult to establish similar models for similar tests.The structural design of the building with isolation bearings puts higher demands on the structural design engineers.In recent years,the over-limit complex structure has been rapidly developed,and the current building codes have emerged in engineering practice.There is no clear and unified method for the seismic design of over-constrained complex structures in China’s building codes.In order to improve the seismic performance and economy of the structure,more and more over-construction buildings are equipped with seismic isolation bearings.However,the over-limit structure with isolation bearing is difficult to design;how to use modern technology to quickly and effectively obtain the structural response of the complex structure with sliding bearing under seismic load in the process of structural design,it seems Particularly important.In order to study the above problems,ETABS software and SATWE software were used to analyze the seismic performance of an over-constructed building with isolated bearings.The sliding plate support is realized in the numerical simulation modeling method;Analysis of the response of an over-limit structure with a seismic isolation bearing under small earthquakes;The key components of the structure were made with medium-seismic elasticity,medium-earthquake unyielding and large earthquakes without yielding design check.Through research and analysis,in order to obtain a valuable reference for similar practical projects.The following work was completed.1)Firstly,the over-limit condition of a construction project with isolation bearing is analyzed;it includes a number of irregular overruns such as a large opening on the roof and a large cantilever on the floor.2)Secondly,simplified modeling without sliding bearings is established.The corresponding working conditions are established according to different simplified models.The modal analysis of different working conditions is carried out with SATWE and ETABS software.The analysis results show that the SATWE software and ETABS software will calculate the constant load loaded on the structure as the mass of the structure.This load equivalent method can easily make the calculation of the simplified model produce large errors.For a seismic isolation building with a seismic isolation bearing,care should be taken when simplifying the modeling without a sliding bearing.3)The sliding plate support is approximated using Friction Isolator in ETABS to create an integral model with a sliding plate support.The FNA method is used to nonlinearly analyze the overrun structure with sliding bearings.4)Three seismic waves were selected,and the time-history analysis and comparison of the building structure under small earthquakes were carried out.The modal,displacement,shearing force,displacement angle and shear-to-weight ratio of the structure under different working conditions were analyzed.According to the analysis results,an over-limit structure with isolation bearing satisfies the requirement of "small earthquake does not damage";for a similar building structure with sliding bearing,an effective simplified modeling method is obtained.5)Finally,the ETABS software is used to realize the analysis of medium and large earthquakes.For the key construction of the structure,the mid-seismic unyielding,the mid-seismic elasticity and the large earthquake are not yielded.