Study On The Seismic Performance Of Limestone Powder-Slag Concrete Shear Wall Structure With High Strength Bolted Connections

In recent years,under the guidance of the emerging architectural concepts of "green building" and "low carbon economy",China has made significant breakthroughs in seismic design,selection of raw materials,and promotion of assembly application.In this thesis,based on the industrial solid waste limestone powder-slag concrete researched by the group,a new "dry connection" shear wall assembly form is selected,and three high-strength bolted limestone powder-slag concrete shear wall structures with different seismic intensities(6,7,8 degrees)are fabricated by similar theory with three corresponding cast-in-place limestone powder-slag concrete shear wall structures,and a combination of proposed static tests and finite element numerical simulations was used to study and compare the seismic performance of these six shear walls.The main concluding remarks of this thesis are as follows:(1)The seismic performance laws of limestone powder-slag concrete shear walls with high-strength bolted connections and limestone powder-slag concrete shear walls with different seismic intensity were obtained.Both cast-in-place structures and precast members have excellent seismic performance such as stable stiffness,high ductility and good energy dissipation capacity.Their damage patterns are basically the same,both showing bending-shear damage patterns.Their basic laws of bearing capacity,strength degradation and stiffness degradation are also basically the same.(2)The seismic performance laws of limestone powder-slag concrete shear wall structures with high strength bolted connections and limestone powder-slag concrete shear walls under different seismic setting intensities were obtained.With the increase of seismic intensity,the ultimate load and initial stiffness of shear walls are enhanced,but their later decreasing tendency is large;the ductility capacity is shown to be enhanced first and then weakened.Under the same seismic intensity,the bearing capacity of precast shear wall is not much different from that of cast-in-place structure,but its ductility,energy dissipation capacity and other seismic performance are weaker than that of cast-in-place structure.(3)A numerical simulation model was established for the high-strength bolted limestone powder-slag concrete shear wall structure and the cast-in-place shear wall,and the seismic performance of the shear wall under horizontal load was compared and analyzed,and the results showed that the numerical simulation model can better reflect the damage form and mechanical properties of this type of shear wall,and the simulation results are in good agreement with the test results.(4)The influence law of parameters such as axial compression ratio,height-width ratio and connection position on the structural bearing capacity of precast shear walls was obtained.For YZ-3(seismic requirements of 8 degrees): the larger the axial pressure ratio,the larger the bearing capacity of the structure,but the faster the bearing capacity degradation and the worse the energy dissipation capacity;the higher the strength grade,the larger the bearing capacity of the structure,but the more likely the structure shows the tendency of brittle damage at the later stage of loading;the height-width ratio is negatively related to the initial stiffness and ultimate bearing capacity of the structure;the node position of the connection near the bottom of the shear wall can improve the The bearing capacity of the structure can be improved,but its ductility is reduced.