一级抗震预应力型钢混凝土空腹桁架转换层框架结构三道防线抗震设防设计方法  

Three-line defense seismic fortification design method for first seismic grade frame with prestressed steel reinforced concrete vierendeel truss transfer storey

作　　者：简斌 李东泽[1,2] 林元 刘郁 JIAN Bin;LI Dongze;LIN Yuan;LIU Yu(Key Laboratory of New Technology for Construction of Cities in Mountain Area of the Ministry of Education,Chongqing 400045,China;School of Civil Engineering,Chongqing University,Chongqing 400045,China;Beijing Urban Construction Design&Development Group Co.,Ltd,Beijing 100161,China)

机构地区：[1]重庆大学山地城镇建设与新技术教育部重点实验室,重庆400045 [2]重庆大学土木工程学院,重庆400045 [3]北京城建设计发展集团股份有限公司,北京100161

出　　处：《建筑结构学报》2021年第1期57-66,共10页Journal of Building Structures

基　　金：国家自然科学基金面上项目(51878100)。

摘　　要：基于"强化转换层及其下部、相对弱化转换层上部"的抗震设计理念,提出了一级抗震大跨度预应力型钢混凝土(PSRC)空腹桁架转换层框架结构"三道防线抗震设防"的设计目标,明确了三道防线的具体划分方法、各防线内力调整措施初步方案以及主要抗震性能的量化控制指标。然后,以两榀不同上抬层数的8度(0.2g)一级抗震的两跨PSRC空腹桁架转换层框架结构为研究对象,在对初步方案设计结构进行罕遇地震水准下弹塑性时程分析的基础上,提出了提高转换柱弯矩增大系数和单侧最小配筋率的新方案,避免了罕遇地震作用下初步方案设计结构转换柱出现塑性铰数量较多、塑性铰转动较大的问题。在罕遇地震作用下,新方案设计结构不发生整体破坏和局部破坏,形成以第一道防线梁充分出现塑性铰耗能的"梁柱混合出铰机制",各防线均满足量化控制指标要求,结构设计达到了"三道防线抗震设防"目标。最后,在极罕遇地震下,进一步检验了新方案下"三道防线抗震设防"设计方法的有效性。Based on the seismic design idea of ‘strengthening transfer storey and its lower part,weakening its upper part relatively’,a design objective of ‘three-line defense seismic fortification’was proposed for first seismic grade frame with prestressed steel reinforced concrete( PSRC) vierendeel truss transfer storey. At the same time,a division method of the three-line defense was proposed,and a preliminary scheme of internal force adjustment measures and main quantitative controlling performance parameters for each line were given. After that,two first grade earthquakeresistant two-span PSRC vierendeel truss transfer storey frames with different numbers of upper storeys were studied under an eight degree( 0. 2 g) seismic fortification level. Then,based on the results from the elasto-plastic timehistory analysis of the structures designed with the preliminary scheme under rare earthquakes,new design schemes,i. e.,increasing the moment amplification factor and increasing the minimum reinforcement ratio for the steel reinforced concrete transfer column were proposed to avoid significant plastic hinges and rotation in the transfer column under rare earthquakes. The results show that the new scheme can avoid overall and local failure,and a ‘beam-column mixed hinge mechanism’can be formed to dissipate energy mainly with the beam hinges in first line defense under rare earthquakes. The quantitative controlling requirements are satisfied for each defense line,and the target of‘three-line defense seismic fortification’is realized. Finally,the seismic performance of the structures employing the new design scheme is studied under extreme-rarely earthquakes to further verify the effectiveness of ‘three-line defense seismic fortification’design method.

关 键 词：预应力型钢混凝土 空腹桁架 转换结构 抗震性能 弹塑性时程分析 三道防线抗震设防 

分 类 号：TU398.7[建筑科学—结构工程] TU311.41