ABSTRACT

Great earthquakes are likely to generate ground motions larger than those considered in design codes (over-design ground motions) and hence leading to a seismic demand that causes severe damages of structural components in general high-rise steel moment-resisting frames (SMRFs). Overall seismic behavior of high-rise SMRFs may be significantly affected by the local failure of members. This paper focuses on the margins of deterioration and collapse of 40-story SMRFs and the equivalent MRFs with concrete-filled tubular (CFT) columns considering the strength deterioration effect in constitutive models designed by current building standards. The input long-period ground motions are synthetic earthquake waves with flat velocity spectral shape. Deterioration and collapse criteria of models based on the peak ground motion velocity are estimated by performing the incremental dynamic analysis (IDA). The results indicate that the collapse mechanism was formed in the lower stories of high-rise SMRFs under the very rare earthquake. The strength and stiffness deterioration significantly amplified the damage extent and the influence degree depends on the sectional compactness of components. And the MRF with concrete-filled tubular (CFT) columns has a higher collapse margin against overall collapse compared with SMRFs.

摘要

大地震可能会产生比设计规范中考虑的更大的地震动（超设计地震动），因此导致地震需求导致一般高层钢抗弯框架（SMRF）中的结构部件严重损坏。高层 SMRF 的整体抗震性能可能会受到构件局部失效的显着影响。考虑到当前建筑标准设计的本构模型中的强度劣化效应，本文重点研究了 40 层 SMRF 和具有混凝土填充管 (CFT) 柱的等效 MRF 的劣化和倒塌裕度。输入的长周期地震动是具有平坦速度谱形状的合成地震波。通过执行增量动态分析 (IDA) 估计基于峰值地震动速度的模型的退化和坍塌标准。结果表明，在这次非常罕见的地震下，高层SMRFs的下层形成了倒塌机制。强度和刚度劣化显着放大了损坏程度，其影响程度取决于构件的截面密实度。与 SMRF 相比，带有混凝土填充管 (CFT) 柱的 MRF 具有更高的抗整体坍塌裕度。强度和刚度劣化显着放大了损坏程度，其影响程度取决于构件的截面密实度。与 SMRF 相比，带有混凝土填充管 (CFT) 柱的 MRF 具有更高的抗整体坍塌裕度。强度和刚度劣化显着放大了损坏程度，其影响程度取决于构件的截面密实度。与 SMRF 相比，带有混凝土填充管 (CFT) 柱的 MRF 具有更高的抗整体坍塌裕度。