Partially Split-level High-rise Shear Wall Structure Earthquake Response Research

With the development of China’s social economy and the progress of building technology,the structural form and function of high-rise buildings have changed greatly.At the same time,the urban population is growing,and the land available for construction is decreasing.In order to make better use of land resources,the form of lower commercial and upper residential is more common.Due to the different functions of commercial and residential buildings,the floor height of commercial buildings is higher than that of residential buildings,which will form staggered floors at the junction.High rise buildings with staggered floors not only meet the needs of use and function,but also bring the problems of complex structure and difficult to grasp the characteristics of mechanical behavior.Especially the structural behavior such as seismic response and seismic performance is more complex than regular structure,which often determines the feasibility of the scheme,even the control design.Therefore,it is necessary to study and demonstrate the response of staggered story structure under earthquake,and take reasonable measures to ensure the safety of the project.Therefore,to carry out research on the seismic response and seismic measures of split-level structures,and to grasp the influence of various factors on the seismic performance of split-level structures,it has important theoretical significance and engineering application value for engineering design.The thesis takes a staggered high-rise shear wall building as the engineering background.By referring to the current national codes and literature,the seismic performance of the staggered high-rise shear wall building is studied and analyzed,and construction suggestions and opinions are given for the design.Personnel provide references when it comes to calculating such structures.The main research contents and conclusions are as follows:(1)Combining the preliminary design plan of a residential building in a shopping mall,analyze the seismic performance of the staggered high-rise structure model and the non-staggered high-rise structure model,and compare the structure period ratio,shear weight ratio,structural lateral displacement and shear wall axial compression ratio.The results show that the period of the staggered structure is longer than that of the non-staggered structure,and the rigidity of the structure is relatively weakened;the seismic shear adjustment coefficient increases,and the seismic force the structure bears increases.For high-rise shear wall structures,the local staggered floor at the bottom has no major influence on the position where the maximum displacement angle appears.For split-level structure and non-staggered-level structure,the shear bearing capacity of the floor lateral force structure gradually decreases from the bottom to the top of the structure,and there is no obvious sudden change in the shear bearing capacity.The axial compression ratio of the shear wall at the bottom of the non-splitting structure is between 0.3 and 0.4,and the axial compression ratio of the shear wall at the bottom of the split-level structure is between 0.4 and 0.5,and the axial compression ratio of the shear wall is significantly increased.(2)In order to further study the characteristics of staggered high-rise structures under earthquake and make up for the deficiency of response spectrum method,elastic time-history analysis of staggered high-rise structures is carried out.By comparing the results of elastic time-history analysis and response spectrum analysis,it is concluded that the maximum seismic shear force of the upper floor of the structure in elastic time-history analysis is 1.2 times larger than the seismic shear force calculated by mode decomposition response spectrum method.According to the results of time history analysis,the seismic shear force of the floor is adjusted by considering the amplification factor of 1.2 in the construction drawing design.(3)Because the staggered story high-rise structure may enter into the elastic-plastic state under the rare earthquake,considering the material nonlinearity,the static elastic-plastic and dynamic elastic-plastic time history analysis of the structure is carried out.The analysis shows that the structure has good bearing capacity and deformation capacity,and can meet the seismic fortification requirements of the code under the rare earthquake.(4)According to the characteristics of elastic-plastic analysis of staggered storey high-rise structure,combined with the seismic performance requirements of the project and the seismic grade of the wall at the staggered storey,the seismic strengthening measures of concrete strength and reinforcement ratio are given,and the suggestion of adopting 120 mm slab thickness and double-layer two-way reinforcement is put forward.