Simulation Analysis On Seismic Performance Of High-strength Concrete Columns With Central Reinforcement Frame Joint

Our country is located between two active seismic belt, is one of the world’s most earthquake-prone countries. Each earthquake disaster had caused enormous losses of people’s lives and property. It urge the research of anti-seismic, thereinto the application of high-strength concrete(HSC) has effectively avoid the phenomenon of “large column cross sections with slight reinforcement” due to restriction of axial compression ratio of columns in an ordinary concrete frame, but its poor plasticity exist. High-strength concrete columns with central reinforcement(HCCCR) frame structure are that made of high-strength concrete with additional longitudinal bars provided at the central parts of their cross sections combined with composite ties to form the cores, which can improve the bearing capacity and ductility of frame structure. The study on its joint are valuable both theoretically and usefully because of its good earthquake resistant behavior.In this paper, HCCCR frame joints were numerically simulated by the finite element software ABAQUS, and the calculation results from reversed cyclic loading models were analyzed. By the method of controlling variables, the influences of the axial compression ratio,core longitudinal reinforcement ratio, core area, column stirrup spacing on the seismic performance were studied, and the general rules of HCCCR frame joints in anti-seismic capability were obtained with different index marks. It showed that HCCCR frame joint has good earthquake-resistant behavior.Based on the stress figure results and common force mechanism of joint, the force mechanism of HCCCR frame joint was derived. Refer to the form of shear capacity design formula from “code for design of concrete structures(GB 50010-2010)”, the core longitudinal reinforcement item was added. Then the influence coefficients of various factors as the axial compression ratio, core longitudinal reinforcement ratio, column stirrup spacing were worked out, and the shear capacity formula of HCCCR frame joint was suggested.