Study on time-varying effects of monitoring data for dam based on the wavelet and EMD

The combined method of wavelet and EMD is used to analyze the time-varying effect of the dam monitoring data. According to some projects, it can be concluded that the curve shapes of the time-varying effect components of the dam safety monitoring data separated by the different wavelet bases are inconsistent; The smoothness of the form of the monitoring data denoising by the wavelet are different, while the forms of the time effect trend components of are more consistent and are more similar to the practical ones, when the dam safety monitoring data denoising have separated by the EMD; The wavelet denoising has reduced the decomposition layers of the dam safety monitoring data and the accumulative end errors on later decomposition. This method improves a lot in the precision of the separation of the time-varying effect components of the dam safety monitoring data, providing more direct analysis and effective support for the state´s assessment of the working dam.