The Analysis Of Seismic-Resistant Behavior In Welded Steel Frames

Steel moment-resisting frames are widely used in the construction especially multi-stories or high-rise structures due to its excellent anti-seismic behavior. Though scholars have studied on seismic-resistant behavior of Steel moment-resisting frames,mostly studied on joint and member of steel frames,researches about the anti-seismis behavior of whole frame were mostly focused in hysteretic behavior and elastic-plastic stability analysis. This paper draws lessons from the research approaches of some scholars on the basis of existing research results and uses nonlinear FEM in analyzing by the numbers about the hysteretic behavior,fracture mechanism and infection factores about anti-seismic behavior of whole frame under circle loading.This paper uses nonlinear FEM considering geometry, material nonlinearity, an thorough finite element simulation of the Steel moment-resisting frames is carried out. The behavior and fracture mechanism of Steel moment-resisting frames (5 classifications include 22 specimens) under cyclic load are analyzed. During the parametric analysis, the influences of slenderness ratios of columns, length of beam, constant axial compression ratios and width-thickness ratios on the hysteretic characteristics of the frame are investtigated, then draw some conclusions: Slenderness ratios of columns is a very important influence factor about anti-seismic behavior of whole frame, with the accretion of the ratio,yield displacement largens,yield load diminishes,ultimate bearing capacity minishes,the frame will have good anti-seismic behavior if the range of ground floor ratios is from 28 to 32;The frame adding stiffener at the bottom column height of 1/12 and 1/6 has good anti-seismic behavior; The frame which the range of the ratios of beam-column rigidity per unit length is from 0.18 to 0.22 has good anti-seismic behavior; With the increasing of ratio of axial compression stress to strength on column, the energy dissipation capability of the frame weakens, the variety of the ratio will inflect the yield displacement greatly given the ratio is less than 0.6,but the change on ultimate bearing capacity is very slightly;Given the ratios of beam-column rigidity per unit...