Fractured rock mass permeation-splitting grouting simulation method and system

Abstract

The invention discloses a fractured rock mass permeation-splitting grouting simulation method and system, and relates to the technical field of grouting simulation methods.The simulation method comprises the steps that a fractured rock mass model is built, and model parameters are set; solving the phase fraction equation to obtain the two-phase fraction of the slurry interface; solving the transmission time tracking equation, and combining with the slurry time-varying curve to obtain a slurry viscosity field; whether the slurry pressure reaches the set splitting pressure or not is judged, and if not, solving is conducted according to the permeation model; if the splitting pressure is reached, the splitting pressure is solved; continuously updating the slurry velocity field and the slurry pressure field until the grouting termination time is reached, and completing the permeation-splitting grouting simulation of the fractured rock mass; according to the method, the slurry permeation process is described on the basis of a Darcy-Blackman method, the rock mass splitting grouting process is described by adopting a viscoplastic constitutive fusion fluid volume method, and therefore the rock mass splitting and slurry flowing process in the fractured rock mass high-pressure grouting process is described.

Description

Technical Field

[0001] The invention relates to the technical field of grouting simulation, and in particular to a broken rock mass penetration-splitting grouting simulation method. Background Art

[0002] In recent years, with the continuous development of underground engineering construction, grouting technology, as an effective means of reinforcement and water blocking, has played an increasingly important role in the construction of fault fracture zone tunnels. When the injected medium is broken rock mass, the slurry will penetrate into the rock mass through the tiny gaps in the rock mass. As the grouting pressure increases, shear cracks will occur in the rock mass and expand. The slurry that has penetrated into the rock mass forms a network or skeleton to reinforce the rock mass, thereby achieving the effect of grouting reinforcement. Through numerical simulation methods, the penetration-splitting process of slurry in broken rock mass can be deeply studied, the diffusion process and reinforcement range of slurry in broken rock mass can be predicted, and a scientific basis can be provided for the allocation of grouting parameters and the optimization of grouting technology, thereby improving the safety and effectiveness of construction.

[0003] Traditional simulation methods usually only focus on the penetration process of slurry in the pores, while ignoring the splitting phenomenon of the injected medium. There are significant differences in the characterization of the numerical simulation methods of the penetration and splitting processes. If the splitting process is ignored, it will often lead to large errors in the simulation results, affecting the accuracy and reliability of the prediction. In addition, when considering the penetration of slurry in porous media, traditional simulation methods often assume the uniformity and continuity of porous media, but in broken rock masses with large porosity, this assumption is no longer valid, resulting in a significant increase in the error of the calculation results. Therefore, traditional numerical methods that only rely on Darcy's law cannot accurately describe the true behavior of slurry in broken rock masses, which in turn affects the evaluation and design optimization of grouting effects. Summary of the invention

[0004] In view of the problems existing in the prior art, the present invention provides a broken rock penetration-splitting grouting simulation method and system, which characterizes the slurry penetration process based on the Darcy-Blackman method and adopts the viscoplastic constitutive fusion fluid volume method to characterize the rock splitting grouting process, thereby describing the rock splitting and slurry flow process during the high-pressure grouting of broken rock.

[0005] The technical solution of the present invention is as follows:

[0006] In a first aspect of the present invention, a method for simulating penetration-splitting grouting of a broken rock mass is provided, characterized in that it comprises:

[0007] Step 1: construct a broken rock model and set model parameters, initialize the slurry state, discretize the broken rock model and divide the grid;

[0008] Step 2: Solve the phase fraction equation to obtain the two-phase phase fraction of the slurry interface; solve the transmission time tracking equation and combine it with the slurry time-varying curve to obtain the slurry viscosity field;

[0009] Step 3: Determine whether the slurry pressure reaches the set splitting pressure. If the splitting pressure is not reached, the slurry velocity field and slurry pressure field of the current time step are obtained according to the Darcy-Blackman equation; if the splitting pressure is reached, the slurry velocity field and slurry pressure field of the current time step are obtained according to the visco-plastic constitutive equation of the broken rock mass;

[0010] Step 4: Repeat steps 2 and 3 to continuously update the slurry velocity field and slurry pressure field until the grouting termination time is reached, thus completing the broken rock mass penetration-splitting grouting simulation.

[0011] In some embodiments of the present invention, the model parameters in step one include density, porosity, cohesion, internal friction angle, elastic modulus and Poisson's ratio; and initializing the slurry state includes setting the slurry initial velocity field, initial slurry pressure field, initial slurry viscosity field and initial phase fraction.

[0012] In some embodiments of the present invention, the phase fraction equation in step 2 is:

[0013]

[0014] Among them, φ is the porosity of the broken rock mass, α i is the phase fraction of the slurry, U=U x +U y +U z is the slurry flow velocity, U x ,U y ,U z are the component velocity vectors of the slurry velocity in the x, y, and z directions respectively;

[0015] After solving the slurry phase fraction at the current time step, the water phase fraction is calculated by α j =φ-α i get.

[0016] In some embodiments of the present invention, in step 2, solving the transmission time tracking equation and combining the slurry time-varying curve to obtain the slurry viscosity specifically includes:

[0017] The transmission time tracking equation is established as:

[0018]

[0019] Where T is the slurry transmission time, φ is the porosity of the crushed rock mass, and U = U x +U y +U z is the slurry flow velocity;

[0020] The functional relationship of the slurry time-varying curve is:

[0021] μ=f(W / C,T);

[0022] Wherein, μ is the slurry viscosity, W / C is the slurry water-cement ratio, and T is the slurry transmission time;

[0023] Combining the slurry water-cement ratio and the transmission time field, the slurry viscosity field at the current time step is obtained.

[0024] In some embodiments of the present invention, the splitting pressure set in step three is set according to the initialized model parameters and based on the DP criterion to set the splitting pressure when the slurry splits the soil in the horizontal direction.

[0025] In some embodiments of the present invention, in step 3, obtaining the slurry velocity field and pressure field at the current time step according to the Darcy-Blackman equation includes:

[0026] According to the porosity and permeability of the broken and fractured rock mass, the Darcy-Blackman equation is constructed and solved to obtain the predicted slurry velocity field.

[0027] The continuity equation and Darcy-Blackman equation are combined to obtain the slurry pressure field;

[0028] Determine whether the predicted slurry velocity field satisfies the continuity equation. If so, output the predicted slurry velocity field and slurry pressure field as the slurry velocity field and pressure field of the current time step. If not, use the slurry pressure field to update the slurry velocity field, and recalculate the predicted slurry velocity field and slurry pressure field until the predicted slurry velocity field satisfies the continuity equation.

[0029] In some embodiments of the present invention, in step 3, obtaining the slurry velocity field and pressure field of the current step according to the viscoplastic constitutive equation of the broken rock mass includes:

[0030] The visco-plastic constitutive equation of the broken rock mass is established to obtain the viscosity of the broken rock mass.

[0031] Solve the momentum equation of the broken rock mass to obtain the splitting velocity field of the broken rock mass;

[0032] Solve the continuity equation of the broken rock mass, update the porosity, and obtain the phase fraction of the broken rock mass;

[0033] Mark the position of the cleavage interface and calculate the cleavage width;

[0034] The momentum equation and velocity equation of the broken rock mass are solved to obtain the slurry pressure field and slurry velocity field at the current time step.

[0035] In some embodiments of the present invention, marking the position of the cleavage interface and calculating the cleavage width comprises:

[0036] First, find the pure solid unit grid and the unit grid of pure water or pure air, and then mark the unit grids where the phase fraction changes sharply. The location of these unit grids is the cleavage interface;

[0037] According to the marked unit grid, ignoring the splitting of the rock mass in the z direction, the spatial distance between the relative units is calculated according to the distance calculation formula. The specific distance calculation formula is:

[0038]

[0039] Where d is the width of the cleavage, N is the total number of marked unit grids, and x i is the horizontal coordinate marking the i-th unit grid, y i is the vertical coordinate marking the i-th unit grid;

[0040] By solving the distance calculation formula, the width of the splitting crack at the current time step is obtained.

[0041] In some embodiments of the present invention, in step 4, after completing the broken rock mass penetration-splitting grouting simulation, the slurry velocity field, slurry pressure field, slurry phase fraction and phase fraction of the broken rock mass are output.

[0042] In a second aspect of the present invention, a broken rock mass penetration-splitting grouting simulation system is provided, characterized in that it comprises:

[0043] The model building module is configured to: build a broken rock model and set model parameters, initialize the slurry state, discretize the broken rock model and divide the grid;

[0044] The phase fraction and slurry viscosity field acquisition module is configured to: solve the phase fraction equation to obtain the two-phase phase fraction of the slurry interface; solve the transmission time tracking equation and combine it with the slurry time-varying curve to obtain the slurry viscosity field;

[0045] The slurry velocity field and slurry pressure field acquisition module is configured to: determine whether the slurry pressure reaches the set splitting pressure, if the splitting pressure is not reached, obtain the slurry velocity field and slurry pressure field of the current time step according to the Darcy-Blackman equation; if the splitting pressure is reached, obtain the slurry velocity field and slurry pressure field of the current time step according to the visco-plastic constitutive equation of the broken rock mass;

[0046] The loop iteration module is configured to continuously update the slurry velocity field and the slurry pressure field until the grouting termination time is reached, thereby completing the fractured rock mass penetration-splitting grouting simulation.

[0047] One or more technical solutions of the present invention have the following beneficial effects:

[0048] (1) The fractured rock mass permeability-splitting grouting simulation method proposed in the present invention obtains the pressure field of the slurry based on the Darcy-Blackman method and the solution of the fluid mechanics equation, analyzes the grouting pressure of each unit grid, and determines whether it reaches the splitting pressure required for rupture. If the grouting pressure of a unit grid has reached the splitting pressure, the unit is identified as entering the splitting state, and the viscoplastic constitutive model is used to characterize the rock mass splitting grouting process; for the units that have not reached the splitting pressure, the calculation continues according to the permeability, thereby effectively capturing the dynamic changes of the slurry under different states, providing an important basis for the optimization of the grouting project.

[0049] (2) The simulation method for describing the penetration of slurry in broken rock mass proposed in the present invention obtains the slurry viscosity field based on the time transmission equation and the slurry time-varying function. Since the porosity of the broken rock mass is relatively large, Darcy's law is corrected and the Darcy-Blackman method is used in combination with the continuity equation to iteratively solve the velocity field and pressure field of the slurry in the broken rock mass at the current time step.

[0050] (3) The simulation method of the fractured rock mass splitting grouting process proposed in the present invention adopts the Herschel-Bulkley non-Newtonian fluid constitutive model to characterize the plastic viscosity of the fractured rock mass during the splitting process for the fractured rock mass unit undergoing splitting; the interface evolution of the slurry-rock mass two-phase flow is characterized by the fluid volume method, and the interface spacing between the two phases is extracted as the crack width of the fractured rock mass; it is assumed that the flow of the slurry in the splitting crack conforms to the secondary velocity distribution law, thereby characterizing the flow of the slurry in the splitting crack. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 The present invention is a method flow chart of the broken rock mass penetration-splitting grouting simulation method.

[0052] Figure 2 It is a schematic diagram of the slurry penetration-splitting of the present invention. DETAILED DESCRIPTION

[0053] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0054] Example 1

[0055] In a typical embodiment of the present invention, a fractured rock mass penetration-splitting grouting simulation method is proposed, such as Figure 1 and Figure 2 As shown, including:

[0056] Step 1: Construct a broken rock model and set model parameters, initialize the slurry state, discretize the broken rock model and divide the grid.

[0057] In order to simulate the working condition that the surrounding rock cracks are filled with broken rock blocks in actual engineering, a broken rock model is constructed (the dimensions of the model in the x and y directions are much larger than those in the z direction, aiming to simulate the splitting of the broken rock in the cracks), and the set model parameters include density, porosity, cohesion, internal friction angle, elastic modulus and Poisson's ratio; the initialization of the slurry state includes setting the slurry initial velocity field, initial slurry pressure field, initial slurry viscosity field and initial phase fraction; then the broken rock model is discretized and gridded, and each unit grid is assigned the above model parameters.

[0058] Step 2: Solve the phase fraction equation to obtain the two-phase phase fraction at the slurry interface; solve the transmission time tracking equation and combine it with the slurry time-varying curve to obtain the slurry viscosity field.

[0059] Specifically, the solution of the phase fraction is:

[0060] The phase fraction of the slurry-water (air) two-phase represents the volume fraction of the two-phase flow in a certain unit grid. By solving the phase fraction equation, the interface of the slurry-water (air) two-phase can be characterized and the diffusion morphology of the slurry can be characterized. The phase fraction equation is specifically:

[0061]

[0062] Among them, φ is the porosity of the broken rock mass, α i is the phase fraction of the slurry, U=U x +U y +U z is the slurry flow velocity, U x ,U y ,U z are the component velocity vectors of the slurry velocity in the x, y, and z directions respectively.

[0063] After solving the slurry phase fraction at the current time step, the water (air) phase fraction can be obtained through α j =φ-α i get.

[0064] Solution of slurry viscosity field:

[0065] Since the viscosity of the slurry changes with time, the slurry transmission time tracking equation is first constructed, the velocity field (initial velocity field) of the slurry at the current time step is read, and the slurry transmission time field is obtained by solving. The slurry transmission time tracking equation is:

[0066]

[0067] Where T is the slurry transmission time, φ is the porosity of the crushed rock mass, and U = U x +U y +Uz is the slurry flow velocity.

[0068] Using a viscometer, the viscosity of the slurry with different water-cement ratios at room temperature was tested over time. To reduce the error, three tests were conducted, and the average value was taken. The results were fitted with a function to obtain the time-varying function of the slurry viscosity, which is:

[0069] μ=f(W / C,T)

[0070] Wherein, μ is the slurry viscosity, W / C is the slurry water-cement ratio, and T is the slurry transmission test time.

[0071] Combining the slurry water-cement ratio and the transmission time field, the slurry viscosity field at the current time step can be obtained.

[0072] Step 3: Determine whether the slurry pressure reaches the set splitting pressure. If the splitting pressure is not reached, the slurry velocity field and slurry pressure field of the current time step are obtained according to the Darcy-Blackman equation; if the splitting pressure is reached, the slurry velocity field and slurry pressure field of the current time step are obtained according to the visco-plastic constitutive equation of the broken rock mass.

[0073] The splitting pressure is set according to the initialized model parameters and the DP criterion to set the splitting pressure when the slurry splits the soil in the horizontal direction. The grouting pressure of each unit grid at the current time step is analyzed (the grouting pressure judged in the first step is the initial grouting pressure, and the grouting pressure judged in the subsequent steps is the calculated grouting pressure) to determine whether it reaches the splitting pressure required for rupture. If the grouting pressure of a unit grid has reached the splitting pressure, the unit Ω 2 It is identified as entering the splitting state, and after the slurry-water (air) phase fraction is updated, the splitting process calculation is performed; and for the unit Ω that has not reached the splitting pressure 1 , then continue to calculate according to the penetration process, and then continue to make judgments.

[0074] Furthermore, the infiltration process is solved by constructing the Darcy-Blackman equation, including:

[0075] According to the porosity and permeability of the broken and fractured rock mass, the Darcy-Blackman equation is constructed and solved to obtain the predicted slurry velocity field.

[0076] The continuity equation and Darcy-Blackman equation are combined to obtain the slurry pressure field;

[0077] Determine whether the predicted slurry velocity field satisfies the continuity equation. If so, output the predicted slurry velocity field and slurry pressure field as the slurry velocity field and pressure field of the current time step. If not, use the slurry pressure field to update the slurry velocity field, and recalculate the predicted slurry velocity field and slurry pressure field until the predicted slurry velocity field satisfies the continuity equation.

[0078] Specifically, according to the porosity and permeability of the broken and fractured rock mass, the Darcy-Blackman equation is constructed, which is:

[0079]

[0080] μ is the viscosity of the slurry, K is the permeability of the broken rock mass, which can be obtained through experiments, φ is the porosity of the broken rock mass, and U = U x +U y +U z is the slurry flow velocity, p is the slurry pressure, ρ is the slurry density, and g is the gravitational acceleration.

[0081] According to the initialized parameters and the initialized slurry pressure field, the predicted slurry velocity field is obtained by solving the Darcy-Blackman equation. At this time, the predicted velocity field does not satisfy the continuity equation. It is necessary to further combine the continuity equation to correct the predicted velocity field. The continuity equation is as follows:

[0082]

[0083] U=U x +U y +U z is the slurry flow velocity.

[0084] The continuity equation and Darcy-Blackman equation are combined to predict the grouting velocity field and solve it to obtain the grouting pressure field. The momentum equation is solved according to the grouting pressure to obtain the grouting velocity field again. The PISO cycle is performed and iterative calculation is performed until convergence to obtain the grouting velocity field and grouting pressure field of the current time step.

[0085] To solve U x For example, given the solution of the velocity component U x Similarly, we can solve the equation for U y and U z , the specific solution equation is:

[0086]

[0087] Furthermore, the steps for solving the flow field during the splitting process include:

[0088] According to the viscoplastic constitutive equation of the broken rock mass, the slurry velocity field and pressure field of the current step are obtained:

[0089] The visco-plastic constitutive equation of the broken rock mass is established to obtain the viscosity of the broken rock mass.

[0090] Solve the momentum equation of the broken rock mass to obtain the splitting velocity field of the broken rock mass;

[0091] Solve the continuity equation of the broken rock mass, update the porosity, and obtain the phase fraction of the broken rock mass;

[0092] Mark the position of the cleavage interface and calculate the cleavage width;

[0093] The momentum equation and velocity equation of the broken rock mass are solved to obtain the slurry pressure field and slurry velocity field at the current time step.

[0094] Specifically, (1) the modified Herschel-Bulkley non-Newtonian fluid constitutive model is used to solve the viscosity of the broken rock mass during the splitting process, which is:

[0095]

[0096] μ p is the viscosity of the broken rock mass, η s is the viscosity coefficient, γ is the shear deformation rate, τ y is the yield stress and n is an exponent representing the shear thickening or shear thinning of the fluid.

[0097] (2) By analogy with the momentum equation of fluid, assuming that the broken rock mass is incompressible, the momentum equation of the broken rock mass is constructed as follows:

[0098]

[0099] Where φ is the porosity of the broken rock mass, 1-φ is the phase fraction of the broken rock mass, and ρ s is the density of the broken rock mass, U s is the splitting speed of the broken rock mass, p is the slurry pressure, g is the gravitational acceleration, is the viscoplastic stress tensor.

[0100] The porosity (initial porosity) of the rock mass at the current time step, the grouting pressure at the current time step, and the rock mass density are read, the momentum equation of the broken rock mass is solved, and the splitting velocity field of the broken rock mass at the current time step is obtained.

[0101] (3) By analogy with the continuity equation of fluid, the continuity equation of broken rock mass is established, which is:

[0102]

[0103] Among them, φ is the porosity of the broken rock mass, 1-φ is the phase fraction of the broken rock mass, and U s is the splitting speed of the broken rock mass.

[0104] According to the velocity of the broken rock mass at the current time step, it is substituted into the continuity equation to solve the porosity of the broken rock mass after splitting, update the porosity of the broken rock mass of each unit grid, obtain the phase fraction of the broken rock mass, and characterize the splitting process of the broken rock mass.

[0105] (4) Characterize the spatial distribution of the rock mass-water (air) two phases and extract the crack width:

[0106] First find the pure solid unit grid (1-φ=1) and the unit grid of pure water or pure air (φ-α i =1 and φ=1), then mark the unit grids where the phase fraction changes sharply, and the locations of these unit grids are the cleavage interfaces;

[0107] According to the marked unit grid, ignoring the splitting of the rock mass in the z direction, the spatial distance between the relative units is calculated according to the distance calculation formula. The specific distance calculation formula is:

[0108]

[0109] Where d is the width of the cleavage, N is the total number of marked unit grids, and x i is the horizontal coordinate marking the i-th unit grid, y i is the vertical coordinate marking the i-th unit grid;

[0110] By solving the distance calculation formula, the width of the splitting crack at the current time step is obtained.

[0111] (5) Solve the velocity equation to obtain the slurry velocity field, which is:

[0112] Since the x and y dimensions of the broken rock mass model are much larger than those of the z direction, it is considered that 2 The broken rock mass in the area undergoes horizontal splitting without vertical cracks. Therefore, the flow of slurry in the x and y directions is considered to be laminar flow and the flow velocity conforms to the law of secondary velocity distribution. The velocity equation is:

[0113]

[0114] Among them, U x is the velocity vector of the slurry in the x direction, U y is the velocity vector of the slurry in the y direction, d is the width of the cleavage crack, γ is the slurry density, which can be determined by experiment, μ is the slurry viscosity, and p is the slurry pressure.

[0115] The velocity of the slurry in the z direction can still be considered as the infiltration process, and the calculation formula is consistent with the infiltration process. By solving the velocity equation, the velocity vector U of the slurry in the x and y directions at the current time step can be obtained. x and U y , and U z By superimposing the vectors, the velocity field of the slurry at the current time step can be obtained.

[0116] (6) Based on the updated porosity of the broken rock mass and the splitting velocity field of the broken rock mass, the momentum equation of the broken rock mass is substituted to obtain the slurry pressure field at the current time step.

[0117] Step 4: Repeat steps 2 and 3 to continuously update the slurry velocity field and slurry pressure field until the grouting termination time is reached, thus completing the fractured rock mass penetration-splitting grouting simulation.

[0118] Specifically, the time step is progressive, and the flow field calculation of the next time step is continued. 1 The area is calculated by the penetration process; for the Ω that has been split 2 After calculating the phase fractions of slurry and water (air) and updating the viscosity of slurry in the area, the splitting process is used for calculation until the final grouting simulation end time to complete the broken rock mass penetration-splitting grouting simulation, and output the slurry velocity field, slurry pressure field, splitting velocity field of broken rock mass, slurry phase fraction and phase fraction of broken rock mass.

[0119] Example 2

[0120] In a typical embodiment of the present invention, a broken rock mass penetration-splitting grouting simulation system is provided, comprising:

[0121] The model building module is configured to: build a broken rock model and set model parameters, initialize the slurry state, discretize the broken rock model and divide the grid;

[0122] The phase fraction and slurry viscosity field acquisition module is configured to: solve the phase fraction equation to obtain the two-phase phase fraction of the slurry interface; solve the transmission time tracking equation and combine it with the slurry time-varying curve to obtain the slurry viscosity field;

[0123] The slurry velocity field and slurry pressure field acquisition module is configured to: determine whether the slurry pressure reaches the set splitting pressure, if the splitting pressure is not reached, obtain the slurry velocity field and slurry pressure field of the current time step according to the Darcy-Blackman equation; if the splitting pressure is reached, obtain the slurry velocity field and slurry pressure field of the current time step according to the visco-plastic constitutive equation of the broken rock mass;

[0124] The loop iteration module is configured to continuously update the slurry velocity field and the slurry pressure field until the grouting termination time is reached, thereby completing the fractured rock mass penetration-splitting grouting simulation.

[0125] Although the above describes the specific implementation mode of the present invention in conjunction with the accompanying drawings, it is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art on the basis of the technical solution of the present invention without creative work are still within the scope of protection of the present invention.

Claims

1. A method for simulating penetration-splitting grouting of broken rock mass, characterized in that: include: Step 1: construct a broken rock model and set model parameters, initialize the slurry state, discretize the broken rock model and divide the grid; Step 2: Solve the phase fraction equation to obtain the two-phase phase fraction of the slurry interface; solve the transmission time tracking equation and combine it with the slurry time-varying curve to obtain the slurry viscosity field; Step 3: Determine whether the slurry pressure reaches the set splitting pressure. If the splitting pressure is not reached, the slurry velocity field and slurry pressure field of the current time step are obtained according to the Darcy-Blackman equation; if the splitting pressure is reached, the slurry velocity field and slurry pressure field of the current time step are obtained according to the visco-plastic constitutive equation of the broken rock mass; Step 4: Repeat steps 2 and 3 to continuously update the slurry velocity field and slurry pressure field until the grouting termination time is reached, thus completing the broken rock mass penetration-splitting grouting simulation.

2. The broken rock mass penetration-splitting grouting simulation method according to claim 1, characterized in that: The model parameters in step one include density, porosity, cohesion, internal friction angle, elastic modulus and Poisson's ratio; the initialization of the slurry state includes setting the slurry initial velocity field, initial slurry pressure field, initial slurry viscosity field and initial phase fraction.

3. The broken rock mass penetration-splitting grouting simulation method according to claim 1, characterized in that: The phase fraction equation in step 2 is: Among them, φ is the porosity of the broken rock mass, α i is the phase fraction of the slurry, U=U x +U y +U z is the slurry flow velocity, U x ,U y ,U z are the component velocity vectors of the slurry velocity in the x, y, and z directions respectively; After solving the slurry phase fraction at the current time step, the water phase fraction is calculated by α j =φ-α i get.

4. The broken rock mass penetration-splitting grouting simulation method according to claim 1, characterized in that: In the step 2, the transmission time tracking equation is solved and the slurry viscosity is obtained by combining the slurry time-varying curve, which specifically includes: The transmission time tracking equation is established as: Where T is the slurry transmission time, φ is the porosity of the crushed rock mass, and U = U x +U y +U z is the slurry flow velocity; The functional relationship of the slurry time-varying curve is: μ=f(W / C,T); Wherein, μ is the slurry viscosity, W / C is the slurry water-cement ratio, and T is the slurry transmission time; Combining the slurry water-cement ratio and transmission time field, the slurry viscosity field at the current time step is obtained.

5. The broken rock mass penetration-splitting grouting simulation method according to claim 1, characterized in that: The splitting pressure set in the step 3 is set according to the initialized model parameters and based on the DP criterion to set the splitting pressure when the slurry splits the soil in the horizontal direction.

6. The broken rock mass penetration-splitting grouting simulation method according to claim 1, characterized in that: In step 3, the slurry velocity field and pressure field at the current time step are obtained according to the Darcy-Blackman equation, including: According to the porosity and permeability of the broken and fractured rock mass, the Darcy-Blackman equation is constructed and solved to obtain the predicted slurry velocity field. The continuity equation and Darcy-Blackman equation are combined to obtain the slurry pressure field; Determine whether the predicted slurry velocity field satisfies the continuity equation. If so, output the predicted slurry velocity field and slurry pressure field as the slurry velocity field and pressure field of the current time step. If not, use the slurry pressure field to update the slurry velocity field, and recalculate the predicted slurry velocity field and slurry pressure field until the predicted slurry velocity field satisfies the continuity equation.

7. The broken rock mass penetration-splitting grouting simulation method according to claim 1, characterized in that: In step 3, the slurry velocity field and pressure field of the current step are obtained according to the viscoplastic constitutive equation of the broken rock mass, including: The visco-plastic constitutive equation of the broken rock mass is established to obtain the viscosity of the broken rock mass. Solve the momentum equation of the broken rock mass to obtain the splitting velocity field of the broken rock mass; Solve the continuity equation of the broken rock mass, update the porosity, and obtain the phase fraction of the broken rock mass; Mark the position of the cleavage interface and calculate the cleavage width; The momentum equation and velocity equation of the broken rock mass are solved to obtain the slurry pressure field and slurry velocity field at the current time step.

8. The broken rock mass penetration-splitting grouting simulation method according to claim 7, characterized in that: The marking of the cleavage crack interface position and the calculation of the cleavage crack width include: First, find the pure solid unit grid and the unit grid of pure water or pure air, and then mark the unit grids where the phase fraction changes sharply. The location of these unit grids is the cleavage interface; According to the marked unit grid, ignoring the splitting of the rock mass in the z direction, the spatial distance between the relative units is calculated according to the distance calculation formula. The specific distance calculation formula is: Where d is the width of the cleavage, N is the total number of marked unit grids, and x i is the horizontal coordinate marking the i-th unit grid, y i is the vertical coordinate marking the i-th unit grid; By solving the distance calculation formula, the width of the splitting crack at the current time step is obtained.

9. The broken rock mass penetration-splitting grouting simulation method according to claim 1, characterized in that: In the step 4, after completing the simulation of the broken rock mass penetration-splitting grouting, the slurry velocity field, the slurry pressure field, the slurry phase fraction and the phase fraction of the broken rock mass are output.

10. A broken rock mass penetration-splitting grouting simulation system, characterized in that: include: The model building module is configured to: build a broken rock model and set model parameters, initialize the slurry state, discretize the broken rock model and divide the grid; The phase fraction and slurry viscosity field acquisition module is configured to: solve the phase fraction equation to obtain the two-phase phase fraction of the slurry interface; solve the transmission time tracking equation and combine it with the slurry time-varying curve to obtain the slurry viscosity field; The slurry velocity field and slurry pressure field acquisition module is configured to: determine whether the slurry pressure reaches the set splitting pressure, if the splitting pressure is not reached, obtain the slurry velocity field and slurry pressure field of the current time step according to the Darcy-Blackman equation; if the splitting pressure is reached, obtain the slurry velocity field and slurry pressure field of the current time step according to the visco-plastic constitutive equation of the broken rock mass; The loop iteration module is configured to continuously update the slurry velocity field and the slurry pressure field until the grouting termination time is reached, thereby completing the fractured rock mass penetration-splitting grouting simulation.

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