Analysis of Space and Particle Parameter Influence to Stability of Soil-rock Mixture Slope

The soil-rock mixture slope has the characteristics of complex physical and mechanical properties and strong nonlinearity, which is greatly affected by geometric factors such as the rock distribution and rock particle size. In order to investigate the effect of geometric parameters on the stability of soil-rock mixture slopes, the ABAQUS software nonlinear analysis method was utilized based on the random generation method of block-shape database proposed by the team. Considering a variety of geometric influencing factors such as the rock content, maximum rock particle size and rock distribution, a large number of finite element models for calculation and analysis were established. The results showed that the safety factor of slope increased with the increase of rock content and the increasing rate was largest when the rock content was in the range of 50%～60%. With the increase of rock content, the standard deviation of the safety factor of the slope in the same particle size group and the difference of model safety factor increased. With the increase of the maximum particle size, the impact of the rock distribution on the safety factor of the model and the standard deviation of the safety factor of the slope in the same particle size group increased, the stability of the slope first decreased and then increased. With the increase of rock content and maximum particle size, the influence of rock distribution on slope stability increased. The influence of the rock distribution on the stability of the soil-rock mixture slope varied with the rock particle size. The existence of large size rock made the sliding face the move away from free face of slope, while the dense small size rocks mostly made the sliding face hackly, both of which increased the stability of the slope. When the rock long axis and slope angle was 90° or 135°, the plastic zone of slope was divergent, the sliding surface was more internal, and the slope stability increased. When the angle between the long axis of the block stone and the slope was 0° or 45°, it was contrary to the above situation. Under normal sedimentary conditions, slope stability decreased with the increase of the ratio of axial length to axial length. The sliding face became smoother and the plastic zone became more concentrated. It can be concluded that the rock content, rock particle size and rock distribution had great influences on the slope stability. With different geometric parameters, slope stability varied greatly and had a certain regularity, which was of certain reference value to the practical projects.