长周期地震动作用下空冷支架结构地震响应分析  

Seismic response analysis of air-cooled supporting structure under long-period ground motion

作　　者：王博 张佳伟 郑芮阁 皮星丽 杨柯 肖康 WANG Bo;ZHANG Jiawei;ZHENG Ruige;PI Xingli;YANG Ke;XIAO Kang(School of Civil Engineering,Chang’an University,Xi’an 710061,China)

机构地区：[1]长安大学建筑工程学院,陕西西安710061

出　　处：《地震工程与工程振动》2023年第4期104-117,共14页Earthquake Engineering and Engineering Dynamics

基　　金：国家自然科学基金项目(51978076,51708037);中央高校基本科研业务费资助项目(300102283202);陕西省自然科学基金项目(2021JM-179)。

摘　　要：长周期地震动低频成分丰富,且持时较长,对自振周期较长的结构影响较大。钢桁架-RC管柱空冷支架结构是一种应用于火电厂的特殊工业结构,实际工程中主要有带斜撑与不带斜撑2种类型,因其跨度较大,自振周期较长,且支撑有大量敏感型的大型昂贵工业设备,在长周期地震动作用下有较大潜在破坏风险。首先,选取了3条长周期地震动和3条普通地震动;然后,建立了带斜撑与不带斜撑的2种空冷支架结构有限元模型,并基于模型结构试验验证其有效性;最后,分析了2种类型空冷支架结构在普通地震动与长周期地震动作用下的位移、剪力及能量响应。结果表明:增加斜撑能有效限制空冷支架结构的位移反应,且在长周期地震动作用下对结构位移限制的效果更为显著,但增加斜撑后结构在长周期地震动作用下的柱顶最大侧移仍大于规范容许值;长周期地震动作用下,空冷支架结构的破坏主要由位移控制;长周期地震动对于带斜撑空冷支架结构体系的塑性累积损伤影响更大;两类结构的累积损伤都主要发生在RC管柱部分,在后期结构设计中应注重RC管柱的耗能能力设计。Long-period ground motions have rich low-frequency components and long duration,and it will cause a great impact on long-period structures.Steel truss-RC tubular column air-cooled supporting structure is a special industrial structure used in thermal power plants.It is mainly composed of two types,with diagonal braces and without diagonal braces.Due to the large span,long period and the support of a large number of sensitive large-scale and expensive industrial equipment of air-cooled supporting structure,it has great potential damage under the long-period ground motion.Firstly,three long-period ground motions and three ordinary ground motions were selected.Then the finite element models of steel truss-RC tubular column air-cooled supporting structure with inclined support and without inclined support were established,and their effectiveness was verified.Finally,the shear force,the displacement and energy response of the two kinds of steel truss-RC tubular column air-cooled supporting structure under ordinary ground motion and long-period ground motion were analyzed.The results show that the addition of diagonal braces can effectively limit the displacement response of the steel truss-RC tubular column air-cooled supporting structure,and the effect is more significant under long-period ground motion.However,the maximum lateral displacement of structure with inclined support under long-period ground motion still exceeds the allowable value.The damage of steel truss-RC tubular column air-cooled supporting structure is mainly controlled by displacement under long-period ground motion.The long-period ground motion has a greater impact on the plastic cumulative damage of the steel truss-RC tubular column air-cooled supporting structure with diagonal braces,and the cumulative damage of the two types of structures mainly occurs in the RC column.In the later structural design,attention should be paid to the energy dissipation capacity design of the RC column.

关 键 词：长周期地震动 空冷支架结构 地震响应 耗能性能 弹塑性时程分析 

分 类 号：TU317[建筑科学—结构工程]