摘要
文中以弹塑性SDOF体系为对象,提出将总输入能、最大瞬时输入能以及能量增长持时作为描述地震能量输入历程的三个特征参数。根据场地条件及地震动峰值速度与峰值加速度比值(V/A)双参数控制选择了不同场地条件下56条强震记录为输入,讨论延性系数的变化对这三个参数的影响。研究表明,随着延性系数的增加,总输入能量谱及最大瞬时输入能量谱在减小谱峰值的同时,谱型整体向短周期移动,形成压缩效应;弹塑性能量增长持时谱较弹性能量增长持时谱更为平滑,其谱值在统计意义上不发生变化;短周期结构延性的增大使得总输入能与最大瞬时输入能增加,但对于中长周期结构,总输入能与最大瞬时输入能随延性系数增加而减少;输入能量在时间轴上的分布模式受延性系数变化的影响不明显,能量时程增长台阶的总长度在各种延性系数条件下趋于一致。
In this paper, total input energy, maximum momentary input energy and duration of input energy process are taken as three descriptive parameters of input energy time histories. The influence of ductility factor on the three parameters is investigated according to 56 earthquake records of 4 site types and the V/A ratio of ground motions. The results indicate that the peaks of total input energy spectrum and maximum momentary input energy spectrum decrease with increasing of ductility factor. The squeezing effect appears with spectrum form moving to short period. The duration spectrum of inelastic input energy process becomes more smoothing than the elastic process with same spectrum statistical values. The total input energy and the maximum momentary input energy increase with the ductility factor in short-period structures, which will decrease in long-period range. The ductility factor has no obvious effect on the distribution pattern on time axis and the growth duration of input energy process.
出处
《地震工程与工程振动》
CSCD
北大核心
2010年第6期56-64,共9页
Earthquake Engineering and Engineering Dynamics
基金
国家自然科学基金项目(50908022)
关键词
能量输入历程
总输入能
最大瞬时输入能
能量增长持时
延性系数
input energy time histories
total input energy
maximum momentary input energy
growth duration of input energy
ductility factor
