预制杯口基础的插入式H型钢柱脚抗震性能研究及参数分析OA

To investigate the seismic performance of socket-type H-section steel column bases in precast cup-shaped foundations under the secondary casting interface failure mode,two specimens were designed with the presence of studs at the bottom flange of the column base as the primary variable.Low-cycle reversed loading tests and numerical simulations were conducted.The failure modes,hysteretic curves,skeleton curves,ductility,strength degradation,stiffness degradation,and energy dissipation capacity of the two specimens were analyzed.Parametric finite element analyses were performed with variation parameters including stud quantity and distribution as well as embedment depth ratio.A nonlinear regression analysis based on experimental and finite element results was conducted to derive a calculation formula for the ultimate bearing capacity of socket-type column bases under secondary casting interface failure mode.Results indicate that both specimens exhibited concrete secondary casting interface failure without steel column base buckling.The arrangement of studs can delay strength degradation and effectively enhance energy dissipation capacity,with better performance observed by increasing stud quantity and positioning them closer to the upper region.The ultimate bearing capacity gradually improved with increasing embedment depth ratio,while steel flange buckling occurred when the ratio reached 2.0.Under casting interface surface failure mode,the values calculated using the proposed ultimate bearing capacity formula demonstrates good agreement with the experimental and finite element results.