复连续小波变换实现地震波在任意时-频域随机相位的方法

Phase Randomization of Ground Motions with Arbitrary Time-frequency Range Using Complex Continuous Wavelets

动力分析过程中输入地震波的选择非常重要,通过扰动自然波生成人工地震波是丰富设计地震波池的方法之一。提出使用复连续小波变换来修改、扰动自然波的方法来拟合人工地震波,以2000年日本鸟取M W6.7地震为研究对象,对比Shannon小波基和Gabor小波基在生成人工波过程中的特点。结果表明:使用改进方法可以在任意指定的时-频域上修改地震波的相位谱从而产生人工波,且Shannon小波对地震波能量的保留优于Gabor小波,故Shannon小波基是更好的选择。

For dynamic analysis,selection of input ground motions is of huge importance.The diversity of the set of input ground motions could be enhanced by simulating the artificial ground motions from natural earthquakes.A methodology utilizing complex continuous wavelets to simulate artificial ground motions areput forward,taking the 2000 Tottori earthquake(M W6.7)as aresearch target,and the characteristics of the Shannon wavelet and the Gabor wavelet are compared in the article.The result shows that the new methodology could have time-frequency domain arbitrarily oriented,and the Shannon wavelet is the optimal choice as it could maintain the power better than the Gabor wavelet.