为改进目前抗震设计加速度反应谱的精度和统计特征在不同周期段有所差异以及由此合成的地震动的低阶谱在频谱特性方面不够真实等问题,基于相对位移反应谱线性模型及其与高阶谱的关系,提出采用唯一函数形式表示的统一光滑加速度反应谱,在此基础上提出兼顾位移谱特性的人工地震动合成方法.数据分析结果表明统一光滑谱具有形式简单、各周期段精度均较高等优点,由此生成地震动信号能够更综合准确地满足加速度谱、速度谱和位移谱的频谱特性需求,精度较高.统一光滑反应谱在函数形式、多阶谱、弹塑性谱精度及多维性等方面具备统一性,可以应用于结构抗震分析及地震动合成.
The current acceleration seismic design spectra has the disvatages including that its precision and the statistics features in different period stage have obvious differences, and the spectrum characteristics of the low- order spectrum based on the artificial signals mismatch the real statistics characteristics. The unified smooth spectrum which adopts unique function was presented based on the linear modle of displacement spectrum, and a new ground motion simulation method considering lower-order spectrum was proposed. The analysis results indicate that the smooth spectrum has the advantages such as simple form, high accuracy for all the period stages. The simulated earthquake signal fulfills the spectrum characteristic requirement for acceleration spectrum, velocity spectrum and displacement spectrum. The smooth spectrum has uniform characteristics including function form, the spectrum characteristics on multiple orders, elasto plasticity and multiple dimensions, and it is suitable for dynamic analysis and ground motion simulation.