Study On The Dynamic Response Rules Of High And Steep Rock Slope Under Earthquake

The slope is the geological body with lateral free face, and the seismic refers to a kind of natural phenomenon of seismic wave which is caused by the mutual extrusion plate caused by collision between the plate edge or internally generated dislocation and rupture of the crust, and then the rapid release of energy caused by vibration. There are many high and steep slopes around the Southwest China. The dynamic response laws of high and steep slope is different from the general earth slope and the lower rock slope. Therefore, it is very important to study the dynamic response laws of high and steep slope.In this paper, the ABAQUS software is used and the finite element and infinite element coupling method is applied. And the homogeneous high and steep slope and the high and steep bedding rock slope are picked to study the dynamic response laws quantitatively and qualitatively.(1) The representative factors such as the geometry parameters of slope(slope height, slope angle and slope shape), the mechanical parameters of slope(elastic modulus, Poisson’s ratio, cohesion and internal friction angle) and the parameters of seismic(amplitude, period, duration and av/ah) among all the factors which have a great influence on the dynamic response laws are selected to study. And the relationships between the horizontal and vertical peak ground acceleration(PGA) and the amplification coefficient and the different position of slope are analyzed for each factor with the same interval in different conditions. Finally, this paper found:1.the dynamic response laws of the peak ground acceleration and its amplification coefficient at the foot slope toe and top of slope, larger horizontal and vertical peak ground acceleration appear at the slope toe under different parameters of av/ah;2.the dynamic response laws of the alternate position of value of horizontal and vertical acceleration under the same parameters, the alternate position of value of horizontal and vertical acceleration is changing as the interal friction angle is changing but it is near the middle of slope surface;3.the dynamic response laws of the position where the maximum value of the horizontal and vertical peak ground acceleration is, which is always near slope toe, middle of slope or top of slope, the maximum value of the horizontal and vertical peak ground acceleration is decreasing with cohesion increasing;4.the relationship between the value of the horizontal and vertical peak ground acceleration and its amplification coefficient and the factors at the same height, the duration has very small effect on the dynamic response laws. At the same time, we find the relationship between vertical peak ground acceleration and its amplification coefficient and the height is easier than that of horizontal ones, and the curves of vertical peak ground acceleration-height and vertical peak ground acceleration amplification coefficient-height is “V”, however, the curves of horizontal peak ground acceleration-height and horizontal peak ground acceleration amplification coefficient-height is complex.(2) The paper selects the representative of high and steep rock bedding slope with single side, high and steep rock bedding slope with double sides, steep rock bedding slope with multilayer and steep rock bedding slope with weak intercalated layer to study the relationship between the horizontal and vertical displacement and the different position of slope under the different parameters of cohesion, internal friction angle or av/ah. Especially, we add the different structure surface position to high and steep rock bedding slope with single side to study the dynamic response laws of it and the thichness of weak intercalated layer to study the dynamic response laws of it. Finally, the horizontal and vertical displacement often appear “surge” at the position where the structure surface exposes, the horizontal and vertical displacement almost equal to zero under the position where the structure surface exposes, and above the position where the structure surface exposes, the horizontal and vertical displacement will no longer changes greatly. Paying attention to the foot of slope, we find that horizontal and vertical displacement appears there which result in moving to the right and vertical settlement of the high and steep rock bedding slope with double sides; the vertical settlement appears at the foot of the steep rock bedding slope with weak intercalated layer but the horizontal displacement appears zero. What is more, the cohesion and internal friction angle have nearly the same influence on those four kinds of high and steep bedding rock slope, but the horizontal and vertical displacement does not increase with decrease in internal friction angle at the position where the structure surface of the high and steep rock bedding slope with single side exposes, and in the high and steep rock bedding slope with double sides, the change of cohesion will cause a large difference of the horizontal and vertical displacement curves under c=0.4MPa and c=0.6MPa and 0.8MPa conditions.(3)The dynamic response laws of safety factor and the horizontal seismic influence coefficient at the structure surfaces under different cohesions and internal friction angles are studied, the safety factor is increasing with the cohesion or internal friction angle increasing, while the horizontal seismic influence coefficient is decreasing with internal friction angle increasing and increasing with cohesion increasing in high and steep rock bedding slope with single side, steep rock bedding slope with multilayer and steep rock bedding slope with weak intercalated layer. But the horizontal seismic influence coefficient is decreasing and then increasing with cohesion increasing in the high and steep rock bedding slope with double sides...