摘要
提出一种基于概率的步行导致结构振动评估方法。现有的评估方法大致有三类:简化方法、基于频域的方法和基于时域的方法,都可以得到步行导致结构共振时产生的峰值加速度,但都没有考虑步行频率的概率分布,因此无法给出加速度值对应的超越概率。行人步行频率大部分分布在一个较窄的范围内,而且基本符合正态分布。该评估方法可以在计算结构竖向振动加速度的基础上,计算振动加速度的概率密度函数。从而可以确定各加速度值的超越概率,对结构振动的风险作出更准确的评估。在此基础上,可以选择具有一定保证率的结构振动加速度反应系数来代表结构的振动性能表现,建议办公建筑取95%保证率的反应系数,天桥结构取具有90%保证率的反应系数来代表结构的振动表现。
A probability-based method for the assessment of walking-induced floor vibration was introduced.Existing methods of assessment fall into three categories,including simplified methods,frequency domain methods,and time domain methods.All these methods can calculate the maximum acceleration of the structural resonance caused by walking,but cannot consider the probability distribution of walking frequency,nor the exceeding probability of the acceleration.Pedestrian walking frequency mostly distributes within a narrow range and generally conforms to the normal distribution.The proposed evaluation method can calculate both the vibration acceleration and its probability density distribution,so the exceedance probability of the acceleration can be calculated which gives a more accurate assessment of the risk of structural vibration.A vibration acceleration response factor with a certain non-exceedance probability can be selected to represent the vibration performance of the structure.It is recommended that office buildings use a response factor with a non-exceedance rate of 95%,and pedestrian bridges use a response factor with a non-exceedance rate of 90%.
作者
李兆凡
潘斌
Mark SARKISIAN
LI Zhaofan;PAN Bin;Mark SARKISIAN(Department of Civil Engineering,Tsinghua University,Beijing 100084,China;Skidmore,Owings&Merrill(Shanghai)Architects Co.,Ltd,Shanghai 200031,China;Skidmore,Owings&Merrill LLP,San Francisco,CA 94111,USA)
出处
《建筑结构》
北大核心
2024年第5期104-110,共7页
Building Structure
关键词
步行
振动
加速度
反应系数
概率
正态分布
保证率
walking
vibration
acceleration
response factor
probability
normal distribution
guarantee rate
作者简介
第一作者:李兆凡,硕士,高级工程师,一级注册结构工程师,主要从事高层建筑结构抗震设计及研究,Email:zhaofan.li@som.com。
