Research On The Seismic Response Characteristics Of Liujiawan Slope

Seismic dynamic response of slopes is a more complex scientific issue.During the "5.12" Wenchuan earthquake,a large number of slopes were damaged,which caused huge damage and losses to the earthquake-stricken areas.This article takes Liujiawan landslide in Qingchuan County triggered by the Wenchuan earthquake as the research object,collects remote sensing data to obtain the topography of the Liujiawan slope before the earthquake and establishes a geological prototype profile model,and uses environmental noise testing to obtain the landslide accumulation area,the back edge of the landslide and the outside Slope data,and analysis using horizontal and vertical spectral ratio(HVSR)and standard spectral ratio(SSR)revealed that the excellent frequency of the 1 # landslide accumulation area is 1-2 Hz,the low frequency band amplification factor is 1.8(<10 Hz),and the high The frequency band amplification factor is 1.6(> 10 Hz),the base rock slope site around the landslide reveals an excellent frequency of 2 Hz,and the spectral ratio amplification factor is 2.0 or less;the excellent frequency of 2 # landslide accumulation area is 1 Hz,4 Hz,HVSR spectral ratio The maximum magnification factor is about 3.2.The bedrock slope outside the landslide reveals an excellent frequency of 2 Hz and a maximum spectral ratio of about 2.3.Compared with the 1 # landslide survey area,the environmental noise data spectrum of the 2 # landslide area is more obvious than the amplification effect.The numerical simulation using two-dimensional discrete element(UDEC)revealed that the 1 # slope geological prototype model contains multiple layers of soft and hard medium interlayer slopes.The dynamic amplification effect is greater than the pure terrain amplification effect(homogeneous model),and the dynamics of the terrain slope break The strongest magnification effect;the 2 # slope geological prototype model includes the dynamic magnification effect of the combination of soft and hard slopes,which increases with the increase of the linear slope elevation.The magnification effect is strongest at the upper elevation of the slope top;in addition,the analysis reveals that the slope refers to the surface and the interior The difference between the amplification factors of different reference points is more obvious,but the remarkable frequency change is not obvious.Three-dimensional finite difference(FLAC3D)numerical simulation revealed that the spectral magnification factor,horizontal and vertical displacement,and stress extreme value of the 1 # slope multi-layer soft and hard medium interlayer slope model are all greater than the homogeneous model,while the slope is vertically enlarged The coefficient is slightly stronger than the horizontal direction,which is consistent with the two-dimensional simulation results revealing the strong amplification effect in the steep slope break region.Comparing environmental noise test data analysis and numerical simulation results,the excellent frequency coupling revealed by the two sites is high,and the numerical simulation amplification factor is much larger than the noise test.This study has certain guiding significance for the evaluation of the dynamic effects of high-intensity mountain slopes,and has important significance in earthquake resistance and disaster reduction.