Seismic Performance Of New Dai Ganlan Light Steel House

Recently more and more new Dai Ganlan light-steel houses have been constructed in Xishuangbanna Dai Autonomous Prefecture,Yunnan Province.The first floor structure of the house is composed of the common steel frame,but the second floor structure and the sloping roof above it are made of cold-formed thin-walled steel.The reason why the Dai Ganlan house is called"new"is that it makes a breakthrough at the traditional way of constructing the Dai Ganlan houses using bamboo,and is replaced by the ordinary steel frame structure and light steel structure.As we all know,Yunnan Province is one of the most earthquake-prone regions in our country and the steel structure has good seismic performance.Therefore,the development of such a structure has a strong practical significance.In the meantime,the State Council has put forward a series of relevant policies on the development of steel structures and fabricated buildings in recent years,and the regulations promulgated by the Xishuangbanna Dai Autonomous Prefecture government require to maintain the traditional Dai architectural style.Therefore,the new Dai Ganlan light steel houses arises at the historic moment in this case.This paper mainly investigates the two aspects of the house,including cold-formed thin-walled steel composite wall,also known as light steel composite wall,and the overall structure.For the light steel composite wall,firstly,the finite element model of it established by ANSYS software was calculated after applying the displacement load on numerical model,then comparing the numerical results calculated with the experimental data obtained from the literatures about the same composite wall.After the finite element model of light-steel composite wall was verified,the finite element models of 36light-weight composite walls are established to analyze how the parameters influence the performance of the light-steel composite walls.These parameters include material of the wall panel,wall aspect ratio,self-tapping screw spacing,vertical load,the size of hole on the composite wall.The results of finite element analysis show that the wall panel materials,the aspect ratio of the wall,the self-tapping screws spacing and the size of hole on the wall has an important influence on the shear behavior of light steel composite wall,but vertical load has little effect on its shear behavior.Finally,based on the equivalent rod method,a simplified model of the light steel composite wall was obtained,and the linear connecting element in SAP2000 was used to simulate the equivalent rod to facilitate the establishment of the overall structural model.For the 90?new Dai Ganlan light steel house,firstly,this paper uses the equivalent rod model of light steel composite wall to simplify the model and establishes its overall structure model with SAP2000.Then this paper does modal analysis to it in order to determine whether the structural model is accurate and realize the basic structure dynamic characteristics of the house.Afterwards does linear seismic response analysis to the overall structural model of the house by using the equivalent base shear method,mode decomposition response spectrum method and elastic time-history analysis method and finally evaluates the seismic performance of the house.The results show that the story drift of the second story of the light steel house is less than 1/300 of the limit in Technical specification for low-rise cold-formed thin-walled steel buildings^[45],and the story drift of the first floor steel frame structure is less than 1/250 of the limit in current seismic design code in China,therefore,the elastic deformations of the structure in the role of the earthquake analysis meet the requirements of the relevant code and specification.The light steel composite wall of the second floor is in elastic state under a magnitude 8?0.2g?earthquake.In the meantime,the design values of the shear forces of the composite wall are all less than the design values of the shear capacity prescribed in the specification^[45],and the walls have a high safety margin.