Research On The Design Method Of Reinforced Nodes With Fan-shaped Lead Viscoelastic Damper

In order to solve the problem of insufficient shear capacity of beam-column joint,an improved softened tension strut model was proposed to provide a theoretical calculation model for the evaluation of shear capacity of joints.Based on the existing research on Sector Lead Viscoelastic Dampers(SLVD),a design method for strengthening joints using SLVD is proposed.The design method is verified a designed finite element model on Open Sees.The main conclusions of this article are as follows:(1)A comparative studies of joint design codes from New Zealand,the United States,Japan,and China is carried out.It shows that American codes has the maximum safety reserves on shear capacity of joints.The Japanese code is the most accurate on calculating the value,but also have a large dispersion;The results of New Zealand Code have the smallest dispersion.Chinese code fully consider various factors but the result have small dispersion.The results of Chinese code overestimate the shear capacity of joints.(2)The calculated values of the modified model are close to the experimental one,with a smaller discrete type,and a certain safety reserve.As the axial pressure ratio increases,the calculated value of the inclination angle of the improved oblique mechanism also increases,indicating that the improved inclination formula can better reflect the impact of the axial pressure ratio.The average ratio between the calculated and experimental values of the improved softened tension and compression bar model for large size joints is 1.02,showing that the improved method can accurately calculate the shear capacity of joints.(3)The error of the finite element models of joint and the SLVD established is within5%,indicating that the modeling method is correct.The calculation value of the shear capacity of the joint strengthened with SLVD is 829.52 k N,which is lower than the shear capacity of the joint.It meets the requirements of the new shear amplification factor.The error between the calculation value and the simulation value is about 6.29%,which is less than10%.It proves the feasibility and effectiveness of the proposed SLVD reinforced joint design method.