Experimental On Seismic Performance Of High Damping ECC And CFRP Bars Reinforced Concrete Shear Wall With Concealed Bracing

Shear walls,the most important energy dissipation and lateral force members in the reinforced concrete structure of high-rise buildings,can effectively increase its bearing capacity,ductility and energy dissipation ability,and improve the force transmission path by setting concealed bracing,according to the researches.In order to further improve the seismic performance of reinforced concrete shear walls with concealed steel plate concealed bracing,two methods are put forward in this paper.One is to cast the wall with high damping ECC materials,which with high ductility and high toughness;the other is to configure CFRP bars which with high tensile strength and linear elastic mechanical properties in the hidden column area.To study the two improvement ways of seismic performance of the shear wall,this paper has completed the quasi-static tests and finite element analysis of a high-damped ECC steel plate concealed shear wall and a CFRP reinforced concrete steel plate concealed shear wall.The main contents are as follows:(1)Some important seismic performance indexes of the two shear walls are obtained through quasi-static cyclic loading tests.Compared with the test results of normal reinforced concrete shear wall with steel plate concealed bracing,it is concluded that the ductility,bearing capacity and energy dissipation ability of the wall are greatly improved with high damping ECC materials,and the seismic performance has been significantly refined,as manifested by the fact that the wall is cracked without breaking;the self-reset property of CFRP reinforced concrete shear walls,in comparison with the energy dissipation ability and ductility,which are enhanced by a small margin,is raised significantly,and the seismic performance of the wall is improved to a certain extent.(2)The models of steel plate concealed bracing shear walls with high damping ECC materials and CFRP bars are established respectively through ABAQUS,a finite element software.Comparing the test data with the software calculation results,it is found that the two are relatively consistent,which indicates that the shear wall models established in this paper are reasonable.(3)On the basis of the finite element shear wall models,the influence of each parameter changes on the seismic performance of high damping ECC steel plate concealed shear wall and CFRP reinforced concrete steel plate concealed shear wall is discussed.The results indicate that the bearing capacity of two shear walls goes up continuously with the increase of axial compression ratio,but the gain is gradually reduced,and the ductility of the wall decreases as the same time.Increasing the number of CFRP bars can expand the bearing capacity of the shear wall but reduce the ductility slightly,and the improvement of the wall is most obvious when the addition is in the concealed column;and if it is added to the inner side further,the improvement gradually decreases.Bearing capacity and ductility of the shear wall increases with the height of high damping ECC materials used in the wall raising,and the improvement is the greatest when the usage is in the area from the bottom of the wall to 1/4 height;and then if the use height continues to increase,the improvement slows down gradually.