高层钢结构考虑损伤累积及裂纹效应的抗震分析

基于钢材在反复荷载作用下的损伤累积力学模型（包括损伤变量D的计算公式，损伤对钢材屈服强度、弹性模量、强化系数的影响以及钢材考虑损伤累积效应的应力－应变滞回关系等）和损伤累积断裂准则，采用改进的数值积分方法对钢构件的滞回曲线进行了计算机仿真，并建立了实用的考虑损伤累积和断裂效应的钢构件恢复力模型。采用这一模型对具有损伤的空间钢框架结构的抗震反应进行分析，并得到了振动台模拟地震试验的验证。抗震分析方法的特点为：能够考虑损伤累积和裂纹效应的影响，能够计算构件的损伤程度，能够计算裂缝产生的时间、部位及其开展，以及能够对钢框架结构遭受多次地震时的情况作真实的反应分析。

Seismic Analysis of Tall Steel Structures with Damage Cumulation and Fracture Effects

Based on the damage cumulative mechanic model of steel under cyclic loading,which includes the calculation of damage index,the effects of damage on the yielding point,modulus of elasticity and hardening coefficient of steel,the stress-strain hysteresis relationship and the fracture criterion,the hysteresis curves of steel members are simulated by adopting the modified numerical integration method.And a practical hysteresis model of steel members which takes the effects of damage cumulation and fracture into consideration is established as well.Seismic analysis of spatial steel frame structures considering the damage cumulation and fracture effects is conducted and the theoretical results are verified by the results of shaking table tests.The advantages of the method proposed in the paper include the following points.First,the effects of damage cumulation and fracture can be taken into account.Second,the damage index of steel members can be calculated.Third,the appearance,the locations and the development of flaws can be analyzed.And Fourth,the responses of steel frame structures under several strong earthquake actions can be rather accurately analyzed.