Study On Hysteretic Energy Dissipation Performance Of RC Column With CRB550 Stirrups

As an important seismic load-bearing member in the frame structure system,the RC column members have a very important influence on the seismic performance of the frame structure.Cold-rolled ribbed steel bar is a new type of steel bar with transverse ribs on the surface of ordinary low-carbon steel after cold rolling.It has good anchoring and plastic properties and is convenient for construction.In the building structure,the strength of CRB550 steel is used instead of HRB335 steel,and the steel consumption is reduced by 16.7%,which is of positive significance for promoting green buildings and achieving sustainable development.Based on the test of RC column members with CRB550 stirrups,the finite element software was used to numerically simulate the column members,and the hysteretic energy dissipation performance of column members with CRB550 stirrups was evaluated according to the energy analysis design method of building structure.The main research contents of this paper are as follows:(1)Introduced the earthquake disaster situation in the world in recent years and energy-based seismic design method,and explained the application of high-strength steel bars in the building structure,and described the research status of RC column members with high strength steel bar.This paper mainly studies the energy dissipation performance of RC column member with CRB550 grade stirrup.(2)Considering the factors such as section size,longitudinal reinforcement ratio and stirrup type,five square-section RC column members with CRB550 grade stirrup and ordinary grade stirrup were designed according to the principle of equal strength,and the low-cycle reciprocating loading test was carried out.The mechanical properties of the failure phenomena,hysteresis curves and skeleton curves of the two column members were compared and analyzed.(3)The concrete damage plasticity model of numerical simulation of RC column members is introduced,and the parameter setting of the model is explained.The material constitutive of steel and concrete is calculated according to the normative constitutive equation and the constrained concrete constitutive equation.The above five RC column members were simulated,and the reliability of the finite element simulation analysis and the accuracy of the test results were verified in terms of the simulation results and the damage cloud diagram,hysteresis curve and skeleton curve of the test results.(4)The RC column members with 13 different section sizes,longitudinal reinforcement ratio,stirrup spacing and stirrup diameter were designed and numerically simulated.Based on the hysteretic energy dissipation theory,the ductility performance,total hysteretic energy,and equivalent viscous damping coefficient are evaluated.The skeleton curve model suitable for RC column members with CRB550 grade stirrup is obtained.(5)Summarize the research content,and discuss the next research direction.