LARGE-SCALE SHAKING TABLE TEST STUDY ON SEISMIC RESPONSE CHARACTERISTICS OF ROCK SLOPE WITH SMALL SPACING TUNNEL

In order to study the dynamic characteristics of rock slope with small spacing tunnel under seismic action, a large-scale shaking table slope model test was designed. The geometric scale was 1:10. In the model test, the Wenchuan (WC) seismic wave was used as the excitation wave to study the characteristics of acceleration response and displacement response of the rock slope model. The excitation directions included the horizontal direction (x), the vertical direction (z) and the horizontal and vertical direction (xz). The results show: 1) Upward along with the slope surface, the acceleration amplification coefficients show nonlinear variation which increases at first and then decreases. Slope changes the input seismic wave spectrum components and has filtered effect at high frequency; 2) In the x- or z-direction excitation, while the acceleration amplification coefficients increase with the increase of the peak loads. In the xz-direction excitation, the coefficients decrease with the increase of the peak loads; 3) 3/5 of slope height is the critical height. The vertical acceleration is amplified more obviously than horizontal acceleration while below the height; but above the height, the horizontal acceleration is amplified more obviously. 4) The horizontal displacement of the slope is mainly affected by the horizontal direction of the seismic wave, and the horizontal displacement increases with the increase of the peak loads. 5) 4/5 of slope height is the critical height, the dynamic displacement peak increases slowly while below the height, but the dynamic displacement peak increases rapidly when above the height and the maximum horizontal displacement is on the top of slope. 6) The dynamic displacement response is related to the excitation direction and location of transducers. These results improve the knowledge of the rock slope with small spacing tunnel under seismic action.