A fractured rock mass penetration-splitting grouting simulation method and system

Abstract

The present invention discloses a method and system for simulating the penetration-splitting grouting of a broken rock mass, and relates to the technical field of grouting simulation methods. The simulation method comprises: constructing a broken rock mass model and setting model parameters; solving a phase fraction equation to obtain the two-phase fraction of a slurry interface; solving a transmission time tracking equation and obtaining a slurry viscosity field in combination with a slurry time-varying curve; judging whether the slurry pressure reaches a set splitting pressure, and if not, solving the problem according to a penetration model; if the splitting pressure is reached, solving the problem for the splitting pressure; continuously updating the slurry velocity field and the slurry pressure field until the grouting termination time is reached, thereby completing the simulation of the penetration-splitting grouting of the broken rock mass; the present invention characterizes the slurry penetration process based on the Darcy-Blackman method, adopts a viscoplastic constitutive fusion fluid volume method to characterize the rock mass splitting grouting process, and thus describes the rock mass splitting and slurry flow process during the high-pressure grouting of the broken rock mass.

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 reinforcement and water blocking method, has played an increasingly important role in the construction of tunnels in fault fracture zones. When the injected medium is fractured rock, the grout penetrates through the small gaps in the rock mass. As the grouting pressure increases, shear cracks form in the rock mass and expand. The slurry that penetrates the rock mass forms a network or skeleton that reinforces the rock mass, thus achieving the grouting reinforcement effect. Through numerical simulation methods, it is possible to conduct in-depth research on the penetration and splitting process of slurry in fractured rock mass, predict the diffusion process of slurry in fractured rock mass and the reinforcement range, and provide a scientific basis for the adjustment of grouting parameters and the optimization of grouting technology, thereby improving the safety and effectiveness of construction.

[0003] Traditional simulation methods typically focus only on the slurry's penetration process in the pores, while ignoring the splitting phenomenon that occurs in the injected medium. Numerical simulation methods for the penetration and splitting processes differ significantly in their characterization. Ignoring the splitting process often leads to large errors in the simulation results, affecting the accuracy and reliability of the predictions. Furthermore, traditional simulation methods often assume the uniformity and continuity of the porous medium when considering the penetration of slurry in porous media. However, in fractured rock masses with high porosity, this assumption no longer holds, resulting in significantly increased errors in the calculation results. Therefore, traditional numerical methods that rely solely on Darcy's law cannot accurately depict the true behavior of slurry in fractured rock masses, which in turn affects the evaluation and design optimization of grouting effects. Summary of the Invention

[0004] In response to the problems existing in the prior art, the present invention provides a method and system for simulating the penetration-splitting grouting of broken rock masses. The method 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 masses.

[0005] The technical solutions of the present invention are 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 by comprising:

[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 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;

[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 viscoplastic 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, completing the fractured 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] Where 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 transport time;

[0023] Combining the slurry water-cement ratio and 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 based on the initialized model parameters and 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 fractured 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 solved simultaneously to obtain the slurry pressure field;

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

[0029] In some embodiments of the present invention, in step three, 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 viscoplastic 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 crack interface position and calculate the crack 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 of the current time step.

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

[0036] First, find the pure solid cell grids and the pure water or pure air cell grids, and then mark the cell grids where the phase fraction changes sharply. The locations of these cell grids are the cleavage interfaces;

[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 marking unit grids, and x i is the horizontal coordinate of 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 fractured rock mass penetration-splitting grouting simulation, the slurry velocity field, slurry pressure field, slurry phase fraction and phase fraction of the fractured rock mass are output.

[0042] In a second aspect of the present invention, a fractured 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 not, 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 viscoplastic constitutive equation of the crushed 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 permeation-splitting grouting simulation method proposed in this invention obtains the slurry pressure field based on the Darcy-Blackman method and the solution of fluid mechanics equations, analyzes the grouting pressure of each unit grid, and determines whether it has reached the splitting pressure required for fracture. If the grouting pressure of a unit grid has reached the splitting pressure, the unit is considered to have entered the splitting state, and the viscoplastic constitutive model is used to characterize the rock mass splitting grouting process; for units that have not reached the splitting pressure, the calculation continues according to the permeation method, thereby effectively capturing the dynamic changes of the slurry under different states and providing an important basis for the optimization of the grouting project.

[0049] (2) The simulation method proposed in the present invention to describe the penetration of slurry in broken rock mass is based on the time transmission equation and the slurry time-varying function to obtain the slurry viscosity field. Due to the large porosity of the broken rock mass, Darcy's law is modified 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 distance 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 This is a flow chart of the broken rock mass penetration-splitting grouting simulation method of the present invention.

[0052] Figure 2 Schematic diagram of slurry penetration-splitting of the present invention. DETAILED DESCRIPTION

[0053] The present invention will be further described below with reference to 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 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] To simulate the actual working conditions in which surrounding rock fractures are filled with broken rock blocks in 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 fractures). 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 divided into grids, 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 phase fraction:

[0060] The phase fraction of the slurry-water (air) two-phase represents the volume fraction of the two-phase flow within a certain unit grid. By solving the phase fraction equation, the interface between 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] Where 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 by α j =φ-α i get.

[0064] Solution of slurry viscosity field:

[0065] Since the slurry viscosity changes with time, the slurry transmission time tracking equation is first constructed, the velocity field of the slurry at the current time step (initial velocity field) is read, and the slurry transmission time field is obtained by solving it. 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 performed, and the average value was taken. The results were then fitted with a function to obtain the time-varying function of the slurry viscosity, which is specifically:

[0069] μ=f(W / C,T)

[0070] Where 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 viscoplastic constitutive equation of the broken rock mass.

[0073] The splitting pressure is set based on the initialized model parameters and the DP criterion, which determines the splitting pressure when the slurry splits the soil horizontally. The grouting pressure of each cell in the current time step is analyzed (the grouting pressure determined in the first step is the initial grouting pressure, and the grouting pressure determined in subsequent steps is the calculated grouting pressure) to determine whether it has reached the splitting pressure required for rupture. If the grouting pressure of a cell has reached the splitting pressure, the cell Ω2 is considered to have entered the splitting state. After updating the slurry-water (air) phase fraction, the splitting process calculation is performed. For cells Ω1 that have not reached the splitting pressure, the calculation continues according to the infiltration process, and then the judgment is continued.

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

[0075] According to the porosity and permeability of the fractured 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 solved simultaneously to obtain the slurry pressure field;

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

[0078] Specifically, the Darcy-Blackman equation is constructed based on the porosity and permeability of the broken and fractured rock mass, 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 acceleration due to gravity.

[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 the Darcy-Blackman equation are solved simultaneously to obtain the grouting pressure field based on the predicted slurry velocity field. The momentum equation is solved based on the grouting pressure to obtain the slurry velocity field again. A PISO loop is performed and iterative calculation is performed until convergence to obtain the slurry velocity field and slurry pressure field at the current time step.

[0085] To solve U x For example, the velocity component U is given x Similarly, we can solve the equation for U y and U z , the specific equation to be solved 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 viscoplastic 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 crack interface position and calculate the crack 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 of 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, specifically:

[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 crushed rock mass is incompressible, the momentum equation of the crushed 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 acceleration of gravity, 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, specifically:

[0102]

[0103] Where 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 in the current time step, it is substituted into the continuity equation to solve the porosity of the broken rock mass after splitting. The porosity of the broken rock mass in each unit grid is updated, and the phase fraction of the broken rock mass is obtained to characterize the splitting process of the broken rock mass.

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

[0106] First find the pure solid unit grid (1-φ=1) and the pure water or pure air unit grid (φ-α i =1 and φ=1), then mark the unit grids where the phase fraction changes sharply. 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 marking unit grids, and x i is the horizontal coordinate of 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, specifically:

[0112] Since the x and y dimensions of the broken rock mass model are much larger than those in the z direction, it is assumed that the broken rock mass in the Ω2 region undergoes horizontal splitting without vertical cracks. Therefore, the slurry flow in the x and y directions is considered to be laminar and the flow velocity conforms to the law of quadratic 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 an 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 of 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, completing the fractured rock mass penetration-splitting grouting simulation.

[0118] Specifically, the flow field calculation continues with the next time step as the time step progresses. For the Ω1 region, where no splitting has occurred, the permeation process is used. For the Ω2 region, where splitting has occurred, the splitting process is used after the slurry and water (air) phase fractions are calculated and the slurry viscosity is updated. This process continues until the final grouting simulation ends, completing the permeation-splitting grouting simulation of the fractured rock mass. The slurry velocity field, slurry pressure field, fractured rock mass splitting velocity field, slurry phase fraction, and fractured rock mass phase fraction are output.

[0119] Example 2

[0120] In a typical embodiment of the present invention, a fractured 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 not, 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 viscoplastic constitutive equation of the crushed 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 embodiments 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 any creative work are still within the scope of protection of the present invention.

Claims

1. A fractured rock mass penetration-splitting grouting simulation method, 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 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; 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 viscoplastic 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, completing the fractured rock mass penetration-splitting grouting simulation; 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 viscoplastic 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 crack interface position and calculate the crack width; The momentum equation and velocity equation of the broken rock mass are solved to obtain the slurry pressure field and slurry velocity field of the current time step.

2. The fractured 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; and initializing the slurry state includes setting the slurry initial velocity field, initial slurry pressure field, initial slurry viscosity field and initial phase fraction.

3. The fractured rock mass penetration-splitting grouting simulation method according to claim 1, characterized in that: The phase fraction equation in step 2 is: in, is the porosity of the broken rock mass, is the phase fraction of the slurry, is the slurry flow velocity, 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 get.

4. The fractured rock mass penetration-splitting grouting simulation method according to claim 1, characterized in that: In the second step, 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: in, is the slurry transfer time, is the porosity of the broken rock mass, is the slurry flow velocity; The functional relationship of the slurry time-varying curve is: ； in, is the slurry viscosity, is the slurry water-cement ratio, 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 fractured rock mass penetration-splitting grouting simulation method according to claim 1, characterized in that: The splitting pressure set in step 3 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.

6. The fractured 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 fractured 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 solved simultaneously to obtain the slurry pressure field; Determine whether the slurry predicted velocity field satisfies the continuity equation. If so, output the slurry predicted velocity field and slurry pressure field as the slurry velocity field and pressure field of the current time step. If not, update the slurry velocity field using the slurry pressure field, and recalculate the slurry predicted velocity field and slurry pressure field until the slurry predicted velocity field satisfies the continuity equation.

7. The fractured rock mass penetration-splitting grouting simulation method according to claim 1, characterized in that: The marking of the cleavage interface position and the calculation of the cleavage width include: First, find the pure solid cell grids and the pure water or pure air cell grids, and then mark the cell grids where the phase fraction changes sharply. The locations of these cell grids are the cleavage interfaces; 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: in, is the width of the cleavage crack, is the total number of marker unit grids, is the horizontal coordinate marking the i-th unit grid, 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.

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

9. A fractured 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 not, 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 viscoplastic constitutive equation of the crushed rock mass; The loop iteration module is configured 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; Among them, 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 viscoplastic 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 crack interface position and calculate the crack width; The momentum equation and velocity equation of the broken rock mass are solved to obtain the slurry pressure field and slurry velocity field of the current time step.

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