Seismic Responses of Lengzhuguan Slope During Kangding Ms5.8 Earthquake

In order to reveal the characteristics of the peak acceleration at different depths of a slope and seismic landslide formation mechanism, a strong earthquake monitoring array was set up in both sides of the Lengzhuguan slope. Five strong vibrograph at different depths but the same altitude were triggered by Kangding Ms 5.8 earthquake occurred on December 25th, 2014. The data reveals that the horizontal peak acceleration at each monitoring site decreases with the increase of depth. It decreases greatly within the surface range of 0 to 45 m and at the inner slope falls at a slow rate. At the monitoring site (99 m from the hole) the horizontal peak acceleration is about 0.6 times the one at the hole. The acceleration response spectrum shows that the amplitudes at monitoring sites decay with the increase of the depth, and the dynamic magnification factor of standard spectra is less than 3.5. Fourier spectrum shows that the amplitudes also decrease gradually from the outside hole to the inside slope, and near the hole, the components of the spectrum become complex.