Shaking Table Test Study On Slope Supported With Anchor And Lattice Beams

As a kind of flexible supporting structure with good ductility, the lattice beam anchor show good anti-seismic effect in the earthquake. At present, however, research on the seismic performance and the dynamic response problems of lattice anchor still need to be improved urgently. Improving the seismic design theory of lattice anchor has been caused intensive concern in the academia and engineering. In the thesis, the dynamic response characteristics of slope model and lattice anchor under the condition of the sine wave excitation was studied by the shaking table text. The results are shown that:(1) Under the function of low frequency vibrated wave,dynamic response of slope reacts strongly while it has an opposite tendency under the function of high frequency vibrated wave.At the same time, the research results show that the elevation of slope has some amplifying action to sine wave, and there is a positive correlation between the dynamic response and the elevation.(2) Under the action of vibration load, the maximum displacement occurred at the top of the sliding body, and the horizontal displacement is greater than vertical displacement, at the same time, the displacement declines with the depth from the crest. Due to the restriction effect of lattice anchor, the upper part of the slide mainly shows rotational and horizontal motion, and the lower part mainly shows shearing motion.(3) Under the same vibration strength, the strain level of the horizontal lattice beam is the same as that of the vertical lattice beam with the same incentives. As for horizontal lattice beam, the strain level of the upper and middle layer is relatively stronger, while it is relatively weaker at the bottom. For the vertical lattice beam, the strains of the middle beams are larger than those of both sides. For the vertical ones, the strain of the tow sides show as“larger-smaller-larger-smaller” style, while the strain of the middle beams show as“smaller-larger-smaller-larger-smaller” style from the top side to the bottom side.(4) When the vibration load is relatively small, anchor is in a “tension-compression”recurrent state, and lattice beam is in a “positive bending deformation-reverse bending deformation” recurrent state; when entering into the damage phase, the stress state of each layer of anchor is mainly in tension, and axial force rapidly increasing;Lattice is mainlyin flexural state, and generates outward flexural trend sharply,furthermore, lattice anchor partly have intense deformation.(5) When the vibration magnitude is relatively small, the peak strain in middle anchor is the largest, and the peak strain at the bottom of the anchor is the smallest. With the vibration magnitude increasing, peak strain increasing rate in top anchor is the fastest.In the process of vibration, the peak strain of each anchor is the largest near the sliding surface, the upper bolt is pulled out with the greatest length, the middle anchor second,and the bottom bolt almost not been pulled out. Therefore, in the slope anchor seismic design,on the premise of ensuring the bottom bolt against sliding, the upper and middle anchor length should be appropriately increased.