Abstract:
Among the retaining wall, anti-slide pile, anchor rod and other retaining structures, the seismic performance of the anchoring system is better, and the possibility of slope instability is quite small. In order to study dynamic response of landslide to the anchor lattice beam under earthquake, large-scale shaking table model test is conducted. In this paper, the sinewave, Wenchuan wave and EL Centro wave are used as the input seismic wave, and the dynamic properties of the anchorage landslide and anchor rod under different excitation intensity and frequency are studied respectively. The results show that the dynamic response of the anchorage system under earthquake can be divided into three stages: the adaptive adjustment stage (0.05
g-0.20
g), the gentle anti-seismic stage (0.20
g-0.40
g) and the intense anti-seismic stage (0.40
g-0.60
g). The natural frequency and PGA amplification factor of the anchorage system shows the trend of "high→low→high". Under different excitation intensity and different excitation waves with different frequency spectrum, the strain mode of anchors in the same column is different accordingly. Under 15 Hz sine wave (close to the natural frequency of the anchorage system), obvious deformation in the upper part of the anchorage body occurs due to the resonance effect. The strain trend of anchors in the same column is changed from "C" shape to "Г"shape with the increasing excitation intensity. However, under the ultra-low frequency 5 Hz sine wave, the strain trend of anchors in the same column retains "Г" shape no matter what the excitation intensity is. Under the Wenchuan waves and El Centro waves, the strain trend of anchors in the same column shows "C"shape, for which the main reason is that the two seismic waves covers different spectral components. In the design of an anchorage landslide in the strong earthquake area, it is suggested that the top anchor and the foot anchor should be strengthened particularly to restrain the tensile cracks near the sliding surface and shear cracks at the slope toe.