Research On Seismic Dynamic Behaviors Of Prestressed Withhold Tenon Type Masonry Buildings

This paper has carried on experimental study on seismic performance of the prestressed mortise and tenon joint type momolithic masonry wall.On the basis of experimental study and the reconstruction model project in Mapo town of Shunyi District,Beijing,the building models have been established by ANSYS finite element analysis software to campare the seismic performance of prestressed power tenon style masonry buildings with traditional and non-prestressed stem tenon style masonry buildings.In this test,we has made 6 prestressed mortise and tenon joint type masonry walls,of which are 4 walls(W2~W5)with prestressed tendons and mortar without stem configured for different axial compression ratios,1 wall(W6)with prestressed tendons without stem and mortar,1 wall(W1)with stem and mortar without prestressed tendons.The 6 walls has been tested respectively by low level of cyclic loading.The test results showed that,as opposed to the wall with stem without prestressed tendons,the seismic performance of walls with prestressed tendons without stem improved significantly,including shear capacity,distribution of crack development,energy dissipation,stiffness degradation,destruction of properties.In addition,the walls' hysteretic curves,deformation and carrying capacity were closely related to the value of prestressing force.The results showed that,W2's ductility was best,W3's hysteretic curves was fullest,W5's carrying capacity was highest.Based on the reconstruction model project in Mapo town of Shunyi District,Beijing,the overall analysis masonry building models have been established by ANSYS finite element analysis software,including the prestressed mortise and tenon joint type masonry building and non-prestressed traditional stem mortise and tenon joint type masonry building.Firstly,the analysis of mode was carried out,then selected six seismic waves,whose time domain and frequency domain were converted to select the appropriate seismic wave.The two models were conducted with dynamic analysis by Nishi-Akashi,which were considered materials' elastic and plastic.According to the actual situation to select the seismic waves' acceleration,the nonlinear time history analysis were respectively conducted by 8 degree earthquake(400 gal)and 9 degrees earthquake(620 gal)to compare two models' parameters,including displacement,base shear,velocity,acceleration,etc.The results showed that,at the same seismic waves,seismic response of masonry structures prestressed and non prestressed masonry structure was different.At the beginning of the seismic loading,two models' dynamic performance was little difference when the structure was still in the elastic stage,but the integrity of the prestressed structure was better than the non-prestressed structure,and the structural seismic response of the prestressed structure was larger than the non-prestressed structure.With the increase of seismic wave loading,the structure' stage turned elastic to plastic.The integrity of non-prestressed structure reduced,by this time,the structural seismic response of the prestressed structure was less than the non-prestressed structure because of the prestressed steel beam.Through comparison and analysis,it can be concluded that under the action of seismic waves,the seismic dynamic performance of new prestressed mortise and tenon joint type masonry building was better.At the same time,it provided theoretical basis for the reconstruction model project in Mapo town of Shunyi District,Beijing...