Study On Seepage Characteristics Of Earth-rock Mixture In Tunnel Fault Zone

The soil-rock mixture is widely distributed in slope engineering,underground engineering,earth-rock dam engineering,highway engineering and other infrastructure construction projects,and often has a very important impact on the stability of the engineering body.Soil-rock mixtures are often characterized by loose,uneven and good water-rich,and their hydrologic characteristics are obviously different from those of general homogeneous rock and soil mass.Therefore,it is of great theoretical and practical significance to study the hydraulic permeability characteristics of soil-rock mixtures and the characteristics of variable mass seepage in waterrich state.In this paper,the hydrologic characteristics of earth-stone mixture were studied,and the macroscopic permeability characteristics of consolidated earth-stone mixture and the variable mass loss characteristics of unconsolidated earth-stone mixture were studied by combining laboratory test and numerical simulation.The main research results were as follows:(1)carry out the experimental study on the main control factors of the soil-rock mixture’s permeability characteristics,and analyze the influence rules of the five factors of the soil-rock mixture’s permeability characteristics,such as the proportion of soil matrix composition,the amount of rock,the size of block stone,the type of cementation,and the cementation dose.The results show that the influence of each factor on the permeability of soil-stone mixture is significantly different,among which the influence of stone content and cementation type is the largest,and the cementation dose required for soil-stone mixture with high stone content to reach the predetermined permeability coefficient is more.(2)carry out the experimental study on the variable mass loss characteristics of soil-rock mixture,reveal the time-varying law of the lost material composition and lost mass in the process of seepage of non-cohesive soil-rock mixture under the interaction of different stone content,particle size distribution and water-rich conditions,and obtain the migration behavior of block stone and soil matrix in the state of seepage.(3)to analyze the impact of earth-rock shape on the flow characteristics,through the way of custom templates CLUMP portrait stone edge Angle characteristics,and designs a method to replace construct different equivalent numerical model of block stone edge Angle,particle microstructure morphology parameters and non-viscous is established the connection between the variable mass flow,soil-rock-mixture reveal grain edge Angle,roughness of soil-rockmixture mesoscopic configuration parameters,such as to change the influence law of seepage failure process quality.(4)based on PFC3D-CFD soil-rock-mixture calculation model is set up,write particle loss statistics program to study hole position of soil-rock-mixture non-viscous seepage process variable mass flow field,velocity field and particle erosion time-varying effect,settlement of time-varying effect,the influence law of porosity and time-varying effect,and compared with the test results.