The Study Of Testing And Analyzing The Characteristic Vibration Of Loess Slope Excited By Construction Source

Most of the rail road between ZhengZhou and Xi'An passes through loess areas. The pivotal cause of affecting deformation is the collapsibility of loess. So, the method compaction pile method was often used for compaction, reinforce the loess foundation with constructing. But the vibration arising from the construction is amplificatory when passing the loess slope. So it causes the very bad huge affect the stability of the loess slope. So, this study tests and analyzes the vibration of loess slope arising from the construction, and finds out the incidence, the propagation character and the attenuation rule between the vibration and distance. And then the study estimates the affect on the loess slope caused by the vibration arising from the construction, and offers some parameters for design the construction project, and make a suggestion.It is taken as a sample that the loess slopes of the entrance of the LvJiaYa tunnel, ShanXian county of HeNan province, which is one part of the special high railway line between ZhengZhou and Xi'An. And then this study tests and analyzes the vibration of loess slope arising from the construction. The data of seismic wave is measured at this loess slope with the SWS machine for exploration and detection when constructing. The attenuation of the surface wave is a little and the power is the strongest, so this paper only analyzes the surface wave data.This study uses the basic theory of frequency spectrum and Fourier transform, filters the original data, and then gets the peak value and basic frequency of the vibration speed, and the coefficient of attenuation of the freedom filed. It is found that the amplificatory effect is very obvious, comparing with the data of freedom filed and analyzing the amplitude, the frequency spectrum, the amplificatory coefficient of the amplitude, the value of dB and the power radio of the survey line at the level ground and the loess slope. The attenuation of the power is much more and the value of dB is increasing alone with the accretion of the distance away from the source, when the Rayleigh wave propagates at the level ground. While the Rayleigh wave propagates at the loess slope, the attenuation of the power is a little, and it isn't obvious that the value of dB is increasing alone with the accretion of the distance away from the source. And it is found that the amplitude and the power increase suddenly, and the value of dB decrease suddenly. That is to say that the amplificatory effect is very obvious, especially at the edge of the flat bed and top of slope.