交通环境振动观测中本底振动去除的功率谱修正法

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振动与冲击 ›› 2011, Vol. 30 ›› Issue (4) : 124-126,.

论文

交通环境振动观测中本底振动去除的功率谱修正法

王福彤1,2;陶夏新1;郑鑫1,3;崔高航4;陈宪麦5

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PSD Correction Method for Removing Background Vibration from Traffic Environmental Vibration Observation

Wang Fu-tong1,2;Tao Xia-xin1;Zheng Xin1,3; Cui Gao-hang4;Chen Xian-mai5

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摘要

摘要：交通系统引起周边环境振动，其观测数据中往往含有本底成分。针对本底成分对真实振动的干扰问题，提出对观测功率谱修正的方法以去除本底振动。假设真实振动与本底振动为互不相关的随机过程，推导了功率谱修正法计算公式，并通过算例考查了方法的有效性。首先，取一条振动记录设定为真实振动曲线，与本底振动记录叠加合成振动数据以模拟现场观测记录。然后假设真实振动未知，分别采用振动级修正法、谱幅值修正法及功率谱修正法估计真实振动曲线。比较计算曲线与设定曲线，判断方法的可行性与准确性。算例显示，功率谱修正法计算的时程、功率谱与设定曲线符合良好，误差低于谱幅值修正法；功率谱修正法、振动级修正法计算的振动级与设定值基本一致，谱幅值修正法计算值略低于设定值。结果说明功率谱修正法克服了振级修正法不能计算时程和功率谱的不足，并且计算结果优于谱幅值修正法。

Abstract

Abstract: Background vibrations typically reside in field observation data for recording traffic-induced environmental vibration in surrounding areas, and may disturb the true vibration signals excited by traffic transportations. A method of PSD revising is suggested here to remove the background vibration from field observed records. Based on the assumption that the true vibration and the background vibration are mutually uncorrelated stochastic processes, calculating formulae of the method were deduced. A group of data was then taken as an example to demonstrate the capability of the method. First, a vibration curve was set as the true vibration data, and was superimposed on a background one to synthesize a filed observation record. Then the true vibration was supposed to be unknown, and was estimated by the vibration level revising approach, the Fourier amplitude revising approach and the proposed PSD revising approach, respectively. The feasibility and accuracy of these approaches were examined by comparing the true vibration setting data with the estimated ones. The results of the example show that the time history and the PSD obtained with the PSD revising approach resemble their setting curves very well, and the errors are smaller than that of Fourier amplitude revising approach. The vibration level calculated by the PSD revising approach or the vibration level revising approach is almost the same as its setting value, but the calculated value by the Fourier amplitude revising approach is relative smaller. It can be concluded that the proposed approach behaves more accurately than the Fourier amplitude revising approach, and produces more types of true vibration data, i.e., time histories and PSDs, than that obtained by the vibration level revising approach.

导出引用

王福彤;陶夏新;郑鑫;崔高航;陈宪麦. 交通环境振动观测中本底振动去除的功率谱修正法[J]. 振动与冲击, 2011, 30(4): 124-126,

Wang Fu-tong;Tao Xia-xin;Zheng Xin;Cui Gao-hang;Chen Xian-mai. PSD Correction Method for Removing Background Vibration from Traffic Environmental Vibration Observation[J]. Journal of Vibration and Shock, 2011, 30(4): 124-126,