高强钢筋超高性能混凝土框架结构易损性分析  

Vulnerability analysis of high-strength steel-reinforced UHPCframe structures

作　　者：贺少锋 邓宗才[1] 李永梅[1] HE Shaofeng;DENG Zongcai;LI Yongmei(Key Lab of Urban Security and Disaster Engineering Ministry of Education,Beijing University of Technology,Beijing 100124,China)

机构地区：[1]北京工业大学城市与工程安全减灾省部共建教育部重点实验室,北京100124

出　　处：《哈尔滨工程大学学报》2024年第3期572-580,共9页Journal of Harbin Engineering University

基　　金：北京市教委科技重点资助项目(KZ20180005008)。

摘　　要：为了研究高强钢筋超高性能混凝土(ultra-high performance concrete, UHPC)结构的抗震能力,本文选取了8条地震动分别对普通钢筋混凝土框架结构(模型Frame-C)和高强钢筋UHPC框架结构(模型Frame-UHPC)进行了增量动力分析,分别以最大层间位移角和谱加速度为结构需求参数和地震动强度参数,拟合出概率地震需求模型,进而计算出2个模型的地震易损性曲线,得到了结构的风险预测和损伤评估结果。研究结果表明:规范性态点下,相较于模型Frame-C,模型Frame-UHPC达到最大中等破坏或严重破坏状态概率时所对应的地震动强度更大,表明模型Frame-UHPC在强震作用下具有更好的抗震能力;小震作用下,模型Frame-UHPC的易损性指数明显小于模型Frame-C,体现了高强钢筋UHPC结构的高强优势。当使用规范性态点时,2个模型在中震和大震作用下的易损性指数相差较小,模型Frame-UHPC不能充分发挥UHPC和高强钢筋的材料优势。通过对文献中配筋UHPC柱数据整理分析,给出了适用于模型Frame-UHPC的建议性态点。与规范性态点相比,建议性态点下模型Frame-UHPC达到极限状态的概率更低,易损性指数也明显减小,小震和中震所应对的易损性指数分别减小了19.5%和42.3%,模型Frame-UHPC在建议性态点下可以更好地发挥其材料优势。To investigate the shock resistance of ultra-high performance concrete(UHPC)structures with high-strength steel,eight earthquakes were selected for the incremental dynamic analysis of the normal reinforced concrete frame structure(model Frame-C)and the high-strength steel-reinforced UHPC frame structure(model Frame-UHPC).Taking the maximum story drift ratio and spectral acceleration as the structural demand and ground motion intensity parameters,respectively,the probabilistic seismic demand model was fitted to calculate the seismic susceptibility curves of the two models,thus deriving the risk prediction and damage assessment results.The results reveal that compared with model Frame-C,the ground motion intensity of model Frame-UHPC is higher when the maximum probability of moderate or severe damage is reached,thus indicating that the model Frame-UHPC has better seismic resistance under the action of strong earthquakes.Furthermore,under the action of small earthquakes,the vulnerability index of the model Frame-UHPC is significantly lower than that of model Frame-C,thereby reflecting the high-strength advantage of the UHPC structure.However,when using the normative performance points,the difference between the vulnerability indices of the two models under moderate or maximum earthquake is small,and the model Frame-UHPC cannot maximize the advantages of UHPC and high-strength steels.Therefore,the suggested performance points suitable for model Frame UHPC are given by sorting out and analyzing the data of reinforced UHPC columns in the literature.Compared with the normative performance points,the probability of Frame-UHPC reaching the ultimate state is lower,and the vulnerability index is significantly reduced when using the suggested performance points.Furthermore,the vulnerability indexes for frequent and moderate earthquakes are reduced by 19.5%and 42.3%,respectively,showing that model Frame-UHPC can better maximize its material advantages by using the suggested performance points.

关 键 词：超高性能混凝土 高强钢筋 易损性分析 增量动力分析 抗震能力 破坏状态 易损性指数 性态点 

分 类 号：TU375.4[建筑科学—结构工程]