偏心支撑钢框架耗能分析的非线性有限元模型

偏心支撑是高层钢结构中一种有效的抗震耗能形式,针对这种结构形式提出了对于变形大、进入塑性的耗能梁段采用退化曲壳单元,其余部分采用梁单元的非线性有限元分析模型。在有限元分析过程中,梁单元考虑了几何非线性,曲壳单元考虑了几何和材料的双重非线性,材料的强化采用了混合强化法则,并编制了相应的计算程序。算例分析表明,用此模型分析偏心支撑钢框架在循环荷载作用下的耗能性能是完全可行的。

NONLINEAR FINITE ELEMENT MODEL FOR ANALYSIS OF ECCENTRICALLY BRACED STEEL FRAME STRUCTURE ENERGY-DISSIPATION

Eccentrically braced steel frames is a kind of steel structure of tall building with well resistant-seismic and energy-dissipation. A new analytical model in which degenerate shell element applies to link beams with large deformation and plastic deformation and beam element applies to other parts of structure is presented. In the process of finite element analysis, geometrical nonlinearity is taken into account for the beam element, while geometrical and material nonlinearities are taken into consideration for the shell element, together with mixed hardening rule. Computer program is complied. Good agreement for analyzing eccentrically braced steel frames energy-dissipation behavior is found between the theoretical predications and experiment result.