摘要
地脉动载荷是影响大型精密装置稳定性的重要因素,地脉动载荷功率谱密度(PSD)包络的计算是制定结构稳定性设计载荷的前提。根据地脉动载荷的数值特征,提出了一种考虑地脉动信号非平稳性的功率谱密度包络的修正方法,经过修正后的地脉动功率谱密度包络避免了传统平稳或局部平稳假设下高振幅信号被平均化的问题,所得功率谱密度包络能够充分反映地脉动载荷的最危险剖面,且与时间长度的选取无关。根据所提方法,计算得到了绵阳花荄监测站2015年—2016年的地脉动功率谱密度包络,为大型光机结构的地脉动载荷确定奠定了基础。
Ground microtremor is an important factor for stability of large precise equipments.Determination of the envelope of power spectral density(PSD)is one of the preliminaries for the stability design of a structure.Combining the numerical characteristics of a ground microtremor,a modification method was proposed considering the non-stationarity of the ground mircotremor signal.The modified PSD envelope can avoid the problem that large-amplitude vibrations may be hided in the traditional stationary or locally stationary assumptions,yielding an envelope that fully reflects the most dangerous part of the ground microtremor load,which is independent to the selection of time length of a PSD curve.The PSD envelopes of the ground microntremor of the Huagai monitoring station in 2015—2016 were calculated,founding basis for the design of large opto-mechanical structures.
作者
郝雨
陈学前
范宣华
王玉军
杜强
胡绍全
HAO Yu;CHEN Xueqian;FAN Xuanhua;WANG Yujun;DU Qiang;HU Shaoquan(Institute of Systems Engineering,China Academy of Engineering Physics,Mianyang 621999,China)
出处
《振动与冲击》
EI
CSCD
北大核心
2019年第24期179-182,196,共5页
Journal of Vibration and Shock
基金
国家自然科学基金(11702279)
中国工程物理研究院总体工程研究所创新与发展基金(2017cxj09)
关键词
地脉动
非平稳
功率谱密度(PSD)
均方根值
ground microtremor
non-stationary
power spectral density(PSD)
root mean square
