| In recent years,prefabricated building,with the advantages of saving resources,shortening construction period,green energy saving and so on,meets the needs of the modern development of the current construction industry,and has been widely concerned and supported by relevant national policies.In the prefabricated structure system,the connection mode,mechanical performance and seismic performance of members are the key research directions of scholars at home and abroad.In this paper,with the help of finite element software,through the selection of appropriate model parameters,a nonlinear finite element model which can reflect the stress characteristics of the new prefabricated concrete shear wall(horse toothed joint)is established,and the test components are explained.The correctness of the calculation model is verified by comparing the simulation results under low cycle reciprocating load with the test results Based on the finite element model,the seismic performance of new prefabricated concrete shear wall members with different height width ratio,different concrete strength grade and different transverse reinforcement diameter in cast-in-place area is studied;the simulation value of normal section bearing capacity of test specimen is compared with the theoretical calculation value,and the design suggestions of horizontal connection of prefabricated concrete shear wall are given.The specific research contents and conclusions of this paper are as follows:(1)Based on the two shear wall specimens in the background test,the finite element software is used for numerical simulation.By comparing the test results with the simulation results,it is concluded that the test value of the ultimate bearing capacity of SW-1 specimen is 2.8% lower than the simulation value,and the test value of the ultimate bearing capacity of PSW-1 specimen is 8.1% lower than the simulation value,which are within the reasonable error range,It shows that the simulation method and parameters are reasonable,and the model can be used to simulate the mechanical performance of prefabricated shear wall.(2)In order to analyze the seismic performance of the new prefabricated horizontal joint shear wall members in a more comprehensive and multi-directional way,based on the verified PSW-1 specimen model of the new prefabricated mayatch precast wall,the finite element software is used to carry out the numerical simulation of different influence parameters,and the different wall height to width ratio,different concrete strength grade,different concrete strength grade,and so on are studied The seismic performance of new fabricated horizontal joint shear wall members under different working conditions with different transverse distribution reinforcement diameters is studied.The results show that the smaller the aspect ratio is,the greater the ultimate bearing capacity is,and the easier brittle failure occurs;The larger the ratio of height to width is,the more the horizontal cracks are,and the easier the bending shear failure is.With the increase of concrete strength,the yield strength and ultimate bearing capacity increase;When the strength grade of concrete is high,the increasing trend of horizontal bearing capacity will weaken;With the increase of concrete strength,the brittleness of prefabricated shear wall members is improved and the failure of members is advanced;The ductility of prefabricated shear wall members also decreases with the increase of concrete strength grade.With the increase of the diameter of transverse reinforcement,the peak bearing capacity and ultimate bearing capacity of the specimens are improved;When the diameter is large enough,the increase of bearing capacity decreases with the increase of diameter.(3)Using specifications and related documents,the theoretical calculation and analysis of the front section bearing capacity of the PSW-1 specimens of the new prefabricated concrete horizontal joint shear wall specimens were carried out and compared with the simulated values to further verify the correctness of the finite element simulation results..The calculation result of the bearing capacity of the normal section of the PSW-1 specimen shows that the theoretical calculation result is318.42 kN,and the ratio of the finite element simulation result of 332.68 kN is 0.96,and the error is within the allowable range.Therefore,it can be judged that The theoretical calculation value of the bearing capacity of the normal section of the part is in agreement with the finite element simulation value.(4)This paper analyzes and compares the seismic performance of the new assembled shear wall under different influence parameters,and puts forward some design suggestions for the research on the horizontal joints of the new assembled shear wall.According to the simulation analysis of the background test,the new prefabricated shear wall component shows good seismic performance as the cast-in-place integral wall.The crack development process of the wall is the same as that of the cast-in-place wall.Finally,the concrete in the compression area is crushed and bent,but the cracks are easy to appear earlier in the horizontal joint between the cast-in-place area and the precast wall,Therefore,the concrete strength grade around the joint should be improved in practical design and application;When the aspect ratio is very small,the shear failure of the specimen is not conducive to earthquake resistance,so the aspect ratio design should not take a very small value;Increasing the strength grade of concrete can improve the bearing capacity of the structure,but when the strength grade is too large,it will produce the result that is not conducive to the seismic resistance of the structure,and also waste building materials. |
PDF Full Text Request