摘要
连续倒塌是结构系统的非线性动力行为,准确评估动力效应是建立简化工程设计方法的核心工作。为了研究钢筋混凝土梁柱子结构动力连续倒塌机理和动力效应,对4个尺寸和材料完全相同的试件分别开展了1次静力和4次动力试验。试验结果表明:动力连续倒塌的应力集中和非对称受力现象更加明显,且受材料应变率效应的影响,梁端受拉裂缝集中开展,受压区混凝土压碎剥落区域较小;考虑到动力损伤和材料应变率对结构自身抗力特征的影响,广义动力抗力能够更加准确地描述实际动力连续倒塌过程中的抗力需求;动力损伤和材料应变率效应使得结构的动力放大效应增强,实际动力放大系数均大于传统理论预测值。
Progressive collapse is a nonlinear dynamic behavior of structure systems. The key issue in establishing the simplified method for the practical engineering design is to evaluate the dynamic effect accurately. To investigate the dynamic progressive collapse mechanism and the dynamic effect of reinforced concrete substructures, one static and four dynamic experiments were conducted on four specimens, which had the identical dimensions and material properties. The results indicated that the stress concentration and asymmetric deformation in the dynamic tests were severer than those in the static test due to the high strain rate effect. Thus, the cracks developed intensively at the beam ends and the concrete spalling area caused by compression was relatively small in dynamic tests. The general dynamic resistance, in which the effects of dynamic damage and high strain rate to the structural resistance were inherently considered, was able to accurately predict the resistance demand in the real progressive collapse process. In addition, the dynamic amplification effect was enhanced by the effect of dynamic damage and high strain rate, thus the practical dynamic amplification factors were larger than the predicted values of the conventional theory.
作者
肖宇哲
李易
陆新征
任沛琪
何浩祥
XIAO Yu-zhe;LI Yi;LU Xin-zheng;REN Pei-qi;HE Hao-xiang(Beijing Key Laboratory of Earthquake Engineering and Structural Retrofit,Beijing University of Technology,Beijing 100124,China;Key Laboratory of Civil Engineering Safety and Durability of Ministry of Education,Tsinghua University,Beijing 100084,China;China Institute of Building Standard Design & Research,Beijing 100048,China)
出处
《工程力学》
EI
CSCD
北大核心
2019年第5期44-52,共9页
Engineering Mechanics
基金
国家自然科学基金项目(51578018)
国家重点研发计划项目(2016YFC0701400)
北京科技新星计划项目(xx2017093)
关键词
钢筋混凝土结构
梁柱子结构
连续倒塌
动力效应
倒塌抗力
reinforced concrete structure
beam-column substructure
progressive collapse
dynamic effect
collapse resistance
