RC框架结构基本自振周期个体间不确定性量化  

QUANTIFICATION OF INTER-BUILDING VARIABILITY OF NATURAL VIBRATION PERIOD OF RC FRAME BUILDINGS

作　　者：项梦洁 陈隽[1,2] XIANG Meng-jie;CHEN Jun(College of Civil Engineering,Tongji University,Shanghai 200092,China;State Key Laboratory of Disaster Reduction in Civil Engineering,Shanghai 200092,China)

机构地区：[1]同济大学土木工程学院,上海200092 [2]土木工程防灾减灾全国重点实验室,上海200092

出　　处：《工程力学》2024年第5期87-95,共9页Engineering Mechanics

基　　金：国家自然科学基金重点项目(52178151);土木工程防灾国家重点实验室项目(SLDRCE19-B-22)。

摘　　要：钢筋混凝土(RC)框架结构是城市区域地震风险评估重要对象,其基本自振周期存在明显个体间变异性,如相同高度周期不同。通常采用的确定性结构高度-周期经验公式主要面向新结构设计,未能考虑既有RC建筑物周期的个体间变异性,影响区域地震风险评估的准确性,因此需要合理量化。该研究通过大量文献检索,收集了不同地区的641栋RC框架结构实测长轴、短轴方向基本周期以及高度、结构形式等信息,开展了严格的数据库清洗,并采用物理准则-数据驱动相结合的方式,建立了高度相依基本周期随机函数模型描述个体间变异性。与经典统计回归基本周期随机模型相比,新模型可以更好地反映结构间基本周期的物理机制差异以及观测数据的联合概率特性,便于在区域地震风险评估中应用。Reinforced concrete(RC)frame structures are important targets in urban seismic risk assessment with their natural vibration periods exhibiting significant inter-building variability,i.e.different periods for the same height.This is neglected in seismic design stage by using a deterministic building height-period formula,as a result,the seismic performance of existing buildings may be incorrectly estimated,and thus the natural vibration period needs to be reasonably quantified in regional seismic risk assessment.In this study,a database containing measured building heights and natural periods in the longitudinal and transverse directions of 641 RC frame buildings is constructed through literature searching,and a height-dependent random period function model is proposed based on stringent data filtering and a physics-guided data-driven methodology to consider the interbuilding variability.The comparison with the classical statistical regression random period model shows that the proposed model can better represent the difference in physical mechanisms of interbuilding natural periods and meanwhile well capture the joint probability characteristics of observed data,therefore could be applicable in regional seismic risk assessment.

关 键 词：RC框架结构 基本自振周期 个体间变异性 随机函数模型 区域地震风险评估 

分 类 号：P315.9[天文地球—地震学]