Numerical Simulation Study Of High-strength Walled Concrete Column Constrained By High-strength Spiral Hoop

This paper proposes a high-strength spiral stirrup constrained high-strength concrete wall column,which is a key component of an assembled high-strength spiral stirrup constrained high-strength concrete wall column residential building,which avoids the frame column protruding from the wall and significantly improves the quality of the residence.High-strength spiral stirrups constrained high-strength concrete wall columns are rectangular concrete columns with a large cross-sectional aspect ratio,and highstrength concrete is constrained by high-strength small-pitch continuous stirrups to improve the problem of poor deformation and energy dissipation of traditional wall columns.In this paper,the seismic performance of high-strength spiral stirrup-restrained high-strength concrete wall columns with a cross-sectional aspect ratio of 3.0 is analyzed.The main work and conclusions are:(1)The nonlinear finite element software ABAQUS is used to consider the material nonlinearity of steel and concrete,the constraining effect of high-strength spiral stirrups on concrete,and the geometric nonlinearity of components,and a realistic finite element model is established.The comparative analysis of the results of the finite element analysis with the test results of 11 different types of stirrup-reinforced concrete square columns and stirrup-reinforced concrete wall columns shows that the finite element model and the failure mode of the test are basically consistent,and the hysteresis analyzed by the finite element model The back curve,skeleton curve,and bearing capacity are basically consistent with the test.In this paper,the finite element model can accurately analyze the mechanical performance of high-strength spiral stirrup-bound high-strength concrete wall columns under low-cycle repeated loads.(2)The typical high-strength spiral stirrups constrained high-strength concrete wall columns were subjected to finite element analysis,and the hysteresis curve,skeleton curve,energy consumption,stirrup stress,concrete damage and stress mechanism analysis were completed.The analysis results show that the overall failure form of the member is bending failure and bending plastic hinges appear at the bottom of the column.The longitudinal reinforcement in the plastic hinge area at the bottom of the column yields,and then the concrete at the column foot crushes and expands outwards,and the stirrups also reach the yield strength.Because the stirrups provide greater lateral restraint,the concrete in the core area still has a certain compressive strength,and the entire specimen still has a certain bearing capacity after failure.The hysteresis curve of the component is relatively full,showing good seismic performance.(3)Parameter analysis of factors that may affect the seismic performance of HighStrength Walled Concrete Column Constrained by High-Strength Spiral Hoop such as:stirrup strength,stirrup spacing,axial compression ratio,shear span ratio,concrete strength,and longitudinal strength.The changing rules of hysteretic curve,skeleton curve,energy consumption capacity and stiffness degradation of High-Strength Walled Concrete Column Constrained by High-Strength Spiral Hoop under different factors are summarized.The analysis results show that reducing the stirrup spacing and increasing the stirrup strength can improve the energy consumption and ductility of the specimen;increasing the axial compression ratio of the specimen will increase the ultimate bearing capacity of the specimen,but the energy consumption of the specimen The capacity is unfavorable;reducing the change of the shear-span ratio of the test piece will increase the ultimate bearing capacity of the test piece;when the concrete strength is high,the specimen has good ductility and seismic performance;changing the longitudinal reinforcement ratio has little effect on the test piece In the same situation,the low reinforcement ratio should be used as much as possible.The results of finite element calculations are summarized,and some construction suggestions for the columns are given.(3)The parameters affecting the seismic performance of high-strength spiral stirrup restraint high-strength concrete wall columns,including stirrup strength,stirrup spacing,axial compression ratio,shear span ratio,concrete strength,and longitudinal reinforcement ratio were analyzed..The results of parameter analysis show that:increasing the strength of the spiral stirrups can improve the deformability of the components;reducing the spacing of the stirrups,the destruction displacement of the components increases,the ductility coefficient increases,and the improvement in energy dissipation capacity is very obvious;increasing the axial compression ratio will cause the components The ductility coefficient and the equivalent viscous damping coefficient are reduced,and the seismic performance is reduced;the reduction of the member’s shearspan ratio will cause the deformation ability of the member to be reduced;under the effective constraint of high-strength stirrups,high-strength concrete still has better deformability;Under a reasonable longitudinal reinforcement ratio,the seismic performance of the specimen does not change significantly.(4)On the basis of a large number of finite element analyses,the design recommendations are as follows: high-strength spiral stirrup-bound concrete wall columns are recommended to use high-grade concrete to reduce the cross-section and save material.The yield strength of stirrups should be greater than 800 Mpa,and the yield strength of stirrups should be greater than 1000 MPa when using C80 concrete.The spacing of the spiral stirrups in the stirrup reinforcement area of the column end of the member should not be greater than 50 mm to ensure that the stirrups fully restrain the concrete.