Study On Dynamic Stability And Stabilization Effect Of Complicated Rock Slopes

The stability of rock slopes under the action of earthquake is one of the hot topics in slope engineering. Investigation shows that the distribution of global seismic belts accord exactly with that of the landslide belts which fully indicates that earthquake has some triggering effects on the instability of rock slopes. Because of the complexity of the engineering materials' composition and the constitutive relation, the particularity of the random load of earthquake, the study on stability of rock slopes under earthquake action becomes very complex. Some research wok has been carried out on the above topic in this paper.At first, some analysis methods for the seismic stability of rock slopes are introduced, which include rigid body limit equilibrium method, model test, numerical analysis. One of the numerical analysis methods, fast Lagrangian difference method is described in detail. Then four methods for the calculation of seismic stability safety factor-pseudo-static method, Newmark method, time history analysis method and strength reduction method are used to evaluate the seismic stability of the four-line slope, and comparative analysis for safety factors of seismic stability of each method is carried out subsequently. Based on the strength reduction method, software FLAC is used to evaluate the safety degree of seismic stability of the slope located in No.1 dam site of Baihtan project. The results indicate that the plastic yielding of weak structural surfaces in the slope under seismic load is notable and these structural surfaces are the potential dangerous slide surfaces. Sensitivity analysis of the connectivity of unloading crack with steep dip angle shows that the deformation of the slope increases apparently with the increase of the connectivity and the value of the connectivity has an obvious effect on the seismic stability of the slope. According to the above conclusion, it is necessary to make some reinforcement for the slope. The stabilization effect of three reinforcement methods—concrete replacement, prestressed cable anchoring, slope cutting are studied. Then the results of the three methods are compared, which shows that concrete replacement has the best effect on the seismic anti-sliding stability of the slope.Based on the engineering practice, some research has been made on the dynamic anti-sliding stability and effect of reinforcement measures of complex rock slopes. Some useful conclusions are also derived which can provide reference for the design of other similar engineerings.