The 2nd Badong International Geohazards Symposium (BIGS2019)

95 / 2019-07-31 22:56:26

A New Method for Numerical Simulation of Soil-Rock Mixture Slope Based on MPM

soil-rock mixture slope; landslide; random field; FLAC3D; excavation and support; REV; MPM; risk assessment

Prevention and Control of Reservoir Geohazards and Ecological Environmental Protection > Technologies of geohazards Prevention and Control

As a widely distributed special geological structure, soil-rock mixture slope is prone to take place geological disasters such as landslide, which brings people huge loss of life and property. While analyzing the stability of soil-rock mixture, the limit equilibrium theory ignores the influence of block rocks and regards the mixture as homogeneous soil slope, leading to a great difference between the calculated results and the actual ones. Traditional FEM cannot simulate the whole process of landslide and its influence, while DEM is often accompanied by huge amount of calculation and difficulties in calibrating parameters when simulating large-scale geotechnical problems, failing to achieve elaborate simulation. To overcome the shortcomings above, taking the side slope of a highway in west as an example, this paper studies the whole process of excavation, support and landslide of soil-rock mixture. The numerical model of soil-rock mixture slope is generated by using random field theory. The equivalent mechanical parameters based on REV are adopted, and the strength reduction method embedded in FLAC3D is used to calculate the stability of each excavation step. For the most dangerous construction step, the probability of landslide is calculated. Finally, the material point method (MPM) is used to simulate the whole process of landslide and its influence range, compared with the numerical simulation results of the same slope of homogeneous soil, and the possible economic losses are evaluated. The results show that the numerical simulation of soil-rock mixture slope landslide based on material point method and random field theory is an efficient and feasible new method, which is closer to the real situation of landslide. It can provide valuable suggestions for excavation and support, landslide and risk assessment of soil-rock mixture slope.