Calculation method for water-rich rock mass fracture grouting diffusion process under slurry-water mixing effect

Abstract

The invention relates to the field of numerical simulation calculation, and particularly discloses a calculation method of a water-rich rock mass fracture grouting diffusion process under a slurry-water mixing effect, which comprises the following steps: (1) respectively calculating the relationship between the width X of a slurry-water mixing area and the grouting time t under one-dimensional fracture and two-dimensional fracture grouting diffusion working conditions; and (2) calculating the relationship between Ry, Rm and t under the two working conditions. And (3) calculating a slurry concentration space distribution equation under the two working conditions. And (4) calculating the spatial distribution equation of the rheological parameters of the slurry under the two working conditions. And (5) respectively calculating grout flow control equations expressed by the grouting flow q under the two working conditions. And (6) calculating a pressure space distribution equation in the grouting diffusion area under the two working conditions. And (7) calculating a relational expression between the grouting pressure and the time at the inlet under the two working conditions. By means of the relational expression, effective prediction of the grouting pressure and the grouting diffusion radius in the grouting diffusion process can be achieved, and the prediction precision of the grouting diffusion process is greatly improved.

Description

Technical Field

[0001] The present invention relates to the field of numerical simulation calculations, and particularly to a calculation method for the grouting diffusion process of water-rich rock mass fractures under the action of slurry-water mixing. Background Art

[0002] Disclosing the information of this background art section is only intended to increase the understanding of the overall background of the present invention, and it is not necessarily regarded as an admission or an implication in any form that this information constitutes the prior art already known to those of ordinary skill in the art.

[0003] Cement slurry has significant characteristics such as low cost, high long-term strength of the stone body, and no environmental pollution, and is widely used in the grouting engineering of fractured rock masses. Cement slurry is a typical slow-setting slurry, and the gel time of the slurry is generally several hours or more. The duration of the cement slurry grouting process in fractured rock masses is generally dozens of minutes. During the entire grouting process, the change in the rheological properties of the cement slurry with time can be ignored, and the rheological properties of the cement slurry mainly depend on the concentration of the slurry itself.

[0004] The grouting diffusion process of cement slurry in fractured rock masses is a process in which the slurry is injected into the fractures and then fills and diffuses in the fractures. There is inevitably a mixture of slurry and groundwater near the grouting diffusion front. This effect will produce a slurry-water mixing zone. As its size continues to expand, coupled with the significant spatial non-uniformity of the slurry concentration inside the mixing zone, it will cause the rheological parameters of the slurry in the entire grouting diffusion area during the grouting diffusion process of fractured rock masses to be difficult to accurately describe, resulting in a large difference between the calculated values of the grouting diffusion radius and the grouting pressure and the actual engineering situation, and further leading to the difficulty in accurately calculating the grouting diffusion process. And the accurate calculation of the grouting diffusion process is the premise for realizing scientific grouting design. Only based on accurate calculations can effective grouting design be implemented. Summary of the Invention

[0005] In view of the above problems, the present invention proposes a calculation method for the grouting diffusion process of water-rich rock mass fractures under the action of slurry-water mixing, effectively overcoming the problems that the calculated values of the grouting diffusion radius and the grouting pressure are significantly different from the actual engineering situation due to the slurry-water mixing zone generated during the grouting process, and the grouting diffusion process is difficult to accurately predict. Specifically, the technical solution of the present invention is as follows.

[0006] A calculation method for the grouting diffusion process of water-rich rock mass fractures under the action of slurry-water mixing, comprising the following steps: (1) Calculate the relationship between the width of the slurry-water mixing zone ∆X and the grouting time t under the one-dimensional grouting diffusion condition of fractures and the two-dimensional circular grouting diffusion condition of fractures respectively.

[0007] (2) Based on the assumed grouting diffusion radius under the one-dimensional grouting diffusion condition in the crack and the two-dimensional circular grouting diffusion condition in the crack R j and the relational expression in step (1), calculate the effective grouting diffusion radius under the above two conditions R y , the maximum grouting diffusion radius R m and the relational expression with the grouting time t .

[0008] (3) Based on the relational expression in step (1) and the R y , R m in step (2), calculate the spatial distribution equations of the cement slurry concentration inside the crack under the one-dimensional grouting diffusion condition in the crack and the two-dimensional circular grouting diffusion condition in the crack respectively: W / C ( r , t ), where the r is the distance from the grouting hole, and the t is the grouting time.

[0009] (4) Based on the W / C ( r , t ) in step (3), calculate the spatial distribution equations of the slurry rheological parameters under the one-dimensional grouting diffusion condition in the crack and the two-dimensional circular grouting diffusion condition in the crack respectively.

[0010] (5) Based on the spatial distribution equations of the slurry rheological parameters in step (4), and according to the flow control equation of the Bingham fluid slurry, calculate the slurry flow control equations expressed by the grouting flow rate q under the above two conditions respectively.

[0011] (6) Integrate the equations obtained in step (5) in the corresponding regions of the fully grouted area and the slurry-water mixing area, and substitute the hydrostatic pressure boundary condition at the maximum grouting diffusion radius R m to obtain the pressure spatial distribution equations in the grouting diffusion region under the one-dimensional grouting diffusion condition in the crack and the two-dimensional circular grouting diffusion condition in the crack.

[0012] (7) Let the distance from the grouting hole r = 0 and r = the radius of the grouting hole r 0 respectively to obtain the grouting pressures at the two distances: p g0 = p ( r = 0, t ),p gr = p ( r = r 0 , t ), substituting it into the pressure space distribution equation in step (6), the relationship between the grouting pressure and time at the inlet under the one-dimensional grouting diffusion condition in the fracture and the two-dimensional circular grouting diffusion condition in the fracture is obtained. Using this relationship, the effective prediction of the grouting pressure and the grouting diffusion radius during the grouting diffusion process can be realized, greatly improving the prediction accuracy of the grouting diffusion process.

[0013] Furthermore, in step (1), through the visualization of the one-dimensional grouting diffusion simulation test of cement slurry and the capture and characterization of the slurry-water mixing zone by the image gray analysis method, the present invention proposes the degree of slurry-water mixing RSR which can be represented by the ratio of the width of the slurry-water mixing zone ∆X to the assumed grouting diffusion radius R j , that is, the following formula (1). In addition, it is found that the relationship between the degree of slurry-water mixing RSR and the assumed grouting diffusion radius R j can be fitted by an exponential function form to realize the quantitative characterization of the degree of slurry-water mixing, that is, the following formula (2): (1); (2); where: the RSR is the degree of slurry-water mixing, the RSR s is the stable value of the degree of slurry-water mixing, and the R j is the assumed grouting diffusion radius under the corresponding condition. The A , B are constants related to factors such as fracture aperture and grouting flow rate.

[0014] Furthermore, in the above formula (1) and formula (2), the assumed grouting diffusion radius R j under the one-dimensional grouting diffusion condition in the fracture and the two-dimensional circular grouting diffusion condition in the fracture are respectively: R j1 =qt / db, R j2 = . Where: q is the grouting flow rate, t is the grouting time, d is the fracture aperture, b is the width of the fracture flow cross-section.

[0015] Further, in step (2), the R y and R m are respectively calculated by the following formula (3): (3); Further, in step (3), the W / C ( r , t ) is calculated by the following formula (4), where: the W / C 0 is the initial water-cement ratio of the grouting slurry, r is the distance from the grouting hole.

[0016] (4); Further, in step (4), the rheological parameters of the slurry include the yield stress τ 0 of the slurry and the viscosity μ of the slurry.

[0017] Further, the spatial distribution equations of the yield stress τ 0 of the slurry and the viscosity μ of the slurry are respectively calculated by the following formula (5), where the τ 0 has the unit of Pa, and the μ has the unit of Pa·s: (5); Further, in step (5), the flow control equation of the Bingham fluid slurry is shown as the following formula (6). Where: the p is the slurry pressure inside the crack, the d is the crack aperture, the r is the distance from the grouting hole, the τ 0( r , t ) and μ ( r , t ) are respectively the spatial distribution equations of the rheological parameters of the slurry shown in formula (5).

[0018] (6); Further, in the formula (6), the average flow velocity of the slurry under the one-dimensional grouting diffusion condition of the crack is calculated by the following formula: q = db , and the average flow velocity of the slurry under the two-dimensional circular grouting diffusion condition of the crack is calculated by the following formula: q = 2πrd , where dis the fracture aperture.

[0019] Further, in step (6), the groundwater pressure under the fracture saturated water environment is taken as the hydrostatic pressure boundary condition.

[0020] Compared with the prior art, the present invention has at least the following beneficial technical effects: In the calculation of the grouting diffusion process in the fractures of water-rich rock masses in the traditional method, there is generally a major problem, that is, the complex influence of the slurry-water mixing effect on the grouting diffusion process has not been fully considered. Most of the prior arts ignore a series of physical and chemical changes caused by the mutual mixing and interaction of the slurry and groundwater in the special environment of the fractures of water-rich rock masses, which leads to a large deviation between the calculation results and the actual grouting situation, and cannot provide an accurate and reliable basis for the grouting design in the tunnel water-rich rock mass fracture environment. The calculation method proposed by the present invention has breakthroughly solved the calculation problem of the grouting diffusion process in the fractures of water-rich rock masses under the influence of the slurry-water mixing effect, realized the accurate calculation of the grouting diffusion process under the influence of the slurry-groundwater mixing effect in the water-rich rock mass fracture environment, and provided a guarantee for the scientific grouting design in the tunnel water-rich rock mass fracture environment. Description of the Drawings

[0021] The attached drawings forming a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention.

[0022] Figure 1 It is a schematic diagram of the slurry-water mixing zone in the rock mass fracture in the following embodiments.

[0023] Figure 2 It is a spatial distribution diagram of the cement slurry concentration inside the fracture in the following embodiments.

[0024] Figure 3 It is a fitting result diagram of the rheological parameters of the cement slurry and W / C in the following embodiments.

[0025] Figure 4 It is an analysis diagram of the force on the slurry flow in the following embodiments.

[0026] Figure 5 It is a comparison diagram of the grouting pressure change curves with time in the following embodiments, where: (a) q = 1.2 L / min, d = 3 mm, (b) q = 1.2 L / min, d = 5 mm, (c) q = 0.6 L / min, d = 3 mm, (d) q = 2.4 L / min, d = 3 mm.

[0027] Figure 6 For the comparison of the slurry pressure spatial distribution curves in the following embodiments, where: for (a), q = 1.2 L / min, d = 3 mm, for (b), q = 1.2 L / min, d = 1 mm, for (c), q = 1.2 L / min, d = 5 mm, for (d), q = 0.6 L / min, d = 3 mm, for (e), q = 2.4 L / min, d = 3 mm. Detailed implementation manners

[0028] It should be noted that the following detailed description is illustrative and is intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used in the present invention have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs.

[0029] It should be noted that the terms used herein are only for describing specific implementation manners and are not intended to limit the exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular forms are also intended to include the plural forms. In addition, it should also be understood that when the terms "comprise" and / or "include" are used in this specification, they specify the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0030] For the convenience of narration, if the words "upper", "lower", "left", and "right" appear in the present invention, they only represent the same directions as the upper, lower, left, and right of the attached drawings themselves, and do not limit the structure. They are only for facilitating the description of the present invention and simplifying the description, rather than indicating or implying that the device or element referred to needs to have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present invention.

[0031] Now, in combination with the attached drawings of the specification and specific embodiments, the calculation method of the grouting diffusion process in water-rich rock mass fractures under the slurry-water mixing action of the present invention will be further described.

[0032] The grouting slurry used in this embodiment is cement slurry, and the initial water-cement ratio of the slurry W / C 0 Adopt the common water-cement ratio of 0.8 in the project. Considering the internal space capacity of the flat fracture and the requirements of grouting time comprehensively, the grouting parameters are set as: grouting flow rate qThree working conditions of 0.6 L / min, 1.2 L / min, and 2.4 L / min, and the fissure aperture d Three working conditions of 1 mm, 3 mm, and 5 mm. Before the start of the grouting simulation test, ensure that the fissure of the flat plate (transparent organic glass plate, with a fissure length of 2 m and a width of 0.1 m) used in the test is in a water-saturated state, and then inject the above-mentioned cement slurry into the fissure of the flat plate at a constant grouting flow rate to realize the dynamic simulation of the development process of the slurry-water mixing zone. The groundwater pressure in the water-saturated environment of the fissure is 0.1 KPa. Then calculate the grouting diffusion process of the water-rich rock mass fissure considering the slurry-water mixing effect, which specifically includes the following steps: (1) Calculate the width of the slurry-water mixing zone under the one-dimensional grouting diffusion condition of the fissure (i.e., the case where the slurry diffuses in one direction in the fissure and the diffusion perpendicular to this direction can be ignored) and the two-dimensional circular grouting diffusion condition of the fissure (i.e., the case where the slurry diffuses in a circular plane in the fissure) ∆X and the relationship with the grouting time t . In this embodiment, through the visualization one-dimensional fissure grouting diffusion simulation test of cement slurry, the slurry-water mixing zone is captured and characterized by the image gray analysis method, and it is proposed that the degree of slurry-water mixing RSR can be represented by the ratio of the width of the slurry-water mixing zone ∆X to the assumed grouting diffusion radius R j , that is, the following formula (1). And through experiments, it is found that the relationship between the degree of slurry-water mixing RSR and the assumed grouting diffusion radius R j can be fitted by an exponential function form to realize the quantitative characterization of the degree of slurry-water mixing, that is, the following formula (2): (1); (2); where: the RSR is the degree of slurry-water mixing, the RSR s is the stable value of the slurry-water mixing degree, and the R j is the assumed grouting diffusion radius under the corresponding working condition.

[0033] Furthermore, the assumed grouting diffusion radii under the one-dimensional grouting diffusion condition of the fissure and the two-dimensional circular grouting diffusion condition of the fissure are respectively: R j1 =qt / db, R j2 = . Where: t is the grouting time, q is the above-mentioned grouting flow rate,d is the aperture of the crack, b is the width of the cross-section of the crack through which fluid flows. The A , B are constants related to factors such as the crack aperture and grouting flow rate.

[0034] Thus, according to the above formulas (1) and (2), the width ∆X of the slurry-water mixing zone under the one-dimensional grouting diffusion condition of the crack and the relationship with the grouting time t ∆ X 1 , and the width ∆X of the slurry-water mixing zone under the two-dimensional circular grouting diffusion condition of the crack and the relationship with the grouting time t ∆ X 2 are shown in the following formula (3): (3); Specifically, according to the above simulation tests, the results of formula (2) under different grouting parameters (i.e., the aforementioned grouting flow rates q = 0.6 L / min, 1.2 L / min, 2.4 L / min, and crack apertures d = 1 mm, 3 mm, 5 mm) are as follows. Substituting them into the above formula (3), the relationships ∆ X 1 under the one-dimensional grouting diffusion condition of the crack and ∆ X 2 under the two-dimensional circular grouting diffusion condition of the crack can be obtained for different grouting parameters.

[0035] ; (2) Based on the above relationships ∆ X 1 , ∆ X 2 , combined with the assumed grouting diffusion radii R j under the one-dimensional grouting diffusion condition and two-dimensional circular grouting diffusion condition of the crack, the effective grouting diffusion radii R y , the maximum grouting diffusion radii R m and the relationship with the grouting time t are calculated respectively. The R y , R m are as Figure 1 shown and calculated by the following formula (4): (4); After substituting the above formula (3) into formula (4), the following results under the above two working conditions are obtained R y 、 R m , as shown in the following formula (5): (5); In the above formula (5), the R y1 、 R m1 are respectively the effective grouting diffusion radius R y 、the maximum grouting diffusion radius R m and the grouting time t relationship under the one-dimensional grouting diffusion condition in fractures, and the R y2 、 R m2 are respectively the effective grouting diffusion radius R y 、the maximum grouting diffusion radius R m and the grouting time t relationship under the two-dimensional circular grouting diffusion condition in fractures. The A 、 B are the same as those in the above formula (2), that is, constants related to factors such as fracture aperture and grouting flow rate. The values of A 、 B under different grouting parameters can be seen from the calculation results of the aforementioned slurry-water mixing degree RSR .

[0036] (3) Based on the above formula (3) and formula (4), calculate the spatial distribution equations of cement slurry concentration under the one-dimensional grouting diffusion condition in fractures and the two-dimensional circular grouting diffusion condition in fractures respectively according to the following formula (6) W / C ( r , t ), where the r is the distance from the grouting hole, and this spatial distribution diagram is as Figure 2 shown.

[0037] (6); Substitute the relational expressions ∆ X 1 、∆ X 2 in the above formula (3) into the above formula (6) respectively, and the spatial distribution equation of cement slurry concentration under the one-dimensional grouting diffusion condition in fractures is obtained W / C 1 ( r , t) Spatial distribution equation of cement slurry concentration under the two-dimensional circular grouting diffusion condition in fractures W / C 2 ( r , t ), respectively, are shown as the following formula (7): (7); In the above formula (7), the W / C 0 is the initial water-cement ratio 0.8 of the grouting slurry, and the A , B are the same as those in the above formula (2).

[0038] (4) Based on the W / C 1 ( r , t ), W / C 2 ( r , t ), the spatial distribution equations of the slurry rheological parameters under the one-dimensional grouting diffusion condition in fractures and the two-dimensional circular grouting diffusion condition in fractures are calculated respectively φ ( r , t ), where the slurry rheological parameters include: slurry yield stress τ 0 (unit: Pa) and slurry viscosity μ (unit: Pa·s), and their spatial distribution equations are calculated respectively by the following formula (8), and the results are as Figure 3 shown: (8); Therefore, substituting the W / C 1 ( r , t ) in the above formula (7) into formula (8) respectively, the spatial distribution equation of the slurry rheological parameters under the one-dimensional grouting diffusion condition in fractures is obtained φ 1 ( r , t ), which includes: the spatial distribution equation of the slurry yield stress W / C 1 ( r , t ) obtained by substituting the τ 0 into the two formulas of formula (8) respectively, and the spatial distribution equation of the slurry viscosity τ 01 ( r , t ) and the spatial distribution equation of the slurry viscosity μ μ1 (r,t) . Specifically, it is shown as the following formula (9).

[0039] Similarly, after substituting W / C 2 ( r , t ) into formula (8) respectively, the spatial distribution equation of the slurry rheological parameters under the two-dimensional grouting diffusion condition of the crack is obtained φ 2 ( r , t ), which includes: after substituting the W / C 2 ( r , t ) into the two formulas of formula (8) respectively, the spatial distribution equation of the slurry yield stress τ 0 and the spatial distribution equation of the slurry viscosity τ 02 ( r , t ) and μ . Specifically, it is shown as the following formula (9). μ 2 (r,t) . Specifically, it is shown as the following formula (9).

[0040] Formula (9); In the above formula (9): W / C 0 is the initial water-cement ratio of the slurry described in formula (7), which is 0.8.

[0041] (5) Calculate the slurry flow control equations expressed by the grouting flow rate q respectively according to the flow control equations of the Bingham fluid slurry under the above two conditions. Specifically, the force analysis of the slurry unit inside the rock mass crack is as Figure 4 shown, and the flow control equation of the Bingham fluid slurry is shown as the following formula (10). Among them: the p is the slurry pressure inside the crack, the d is the crack aperture, and the r is the distance from the grouting hole. The average slurry flow velocity under the one-dimensional grouting diffusion condition of the crack is calculated by the following formula: q = db , and the average slurry flow velocity under the two-dimensional circular grouting diffusion condition of the crack is calculated by the following formula: q = 2πrd .

[0042] (10); Among them, the μ(r,t)including the above-mentioned μ 1 (r,t), μ 2 (r,t) , the τ 0 ( r , t ) includes the above-mentioned τ 01 ( r , t ). τ 02 ( r , t ). Thus, the slurry flow control equations expressed by the grouting flow rate q under the one-dimensional grouting diffusion condition and the two-dimensional circular grouting diffusion condition in the fracture are shown as the following formulas (11) and (12) respectively: (11); (12); (6) Integrate the control equations shown in formulas (11) and (12) of step (5) in the corresponding regions of the slurry-saturated zone and the slurry-water mixing zone, and substitute the hydrostatic pressure boundary condition at the maximum grouting diffusion radius (i.e., the groundwater pressure in the fracture-saturated water environment mentioned above, which is 0.1 KPa), and the pressure spatial distribution equations in the grouting diffusion regions under the one-dimensional grouting diffusion condition in the fracture and the two-dimensional circular grouting diffusion condition in the fracture p 1 ( r,t ). p 2 ( r,t ), are shown as the following formula (13) respectively. Among them, p w is the hydrostatic pressure.

[0043] (13); (7) Respectively let the distance from the grouting hole r = 0, r = the radius of the grouting hole r 0, and the grouting pressure p g = p( r = 0 , t ), p g = p ( r = r 0 ,t) Substitute it into the equation shown in Equation (13) of the above step (6) to obtain the relationship between the grouting pressure and time at the inlet under the one-dimensional grouting diffusion condition of the crack and the two-dimensional circular grouting diffusion condition of the crack p g1 、 p g2 which are respectively shown in the following Equation (14): (14); Through the relationship between the grouting pressure and time (the theoretical model of the crack grouting diffusion process) shown in the above Equation (14), the accurate calculation of the grouting diffusion process in the water-rich rock mass crack environment can be realized under the consideration of the slurry-water mixing effect (denoted as Model A). In addition, ignoring the effect of the slurry-water mixing zone and regarding the interface between the slurry and groundwater as a complete displacement interface, the calculation results without considering the slurry-water mixing effect can be obtained (denoted as Model B).

[0044] As mentioned above, the grouting flow rate is set to q = 0.6 L / min, 1.2 L / min, 2.4 L / min for three working conditions, and the crack aperture is set to d = 1 mm, 3 mm, 5 mm for three working conditions. Then, according to the above Model A and Model B, the curves of the grouting pressure varying with time and the spatial distribution curves of the slurry pressure at different times of the test results under these three working conditions are calculated respectively. The results are respectively as Figure 5 、such as Figure 6 shown. It can be seen that compared with the grouting theoretical model without considering the slurry-water mixing effect (Model B), the grouting theoretical model considering the slurry-water mixing effect (Model A) proposed in this embodiment obtains the grouting pressure calculation results that are closer to the test data results, thus proving the necessity of considering the slurry-water mixing effect in the rock mass crack grouting diffusion process and the correctness of the theoretical model of the crack grouting diffusion process considering the slurry-water mixing effect.

[0045] The technical solution of this embodiment obtains the relationship equation between the width of the slurry-water mixing zone and time and the spatial distribution equation of the slurry rheological parameters in the slurry-water mixing zone. On this basis, a theoretical model of the rock mass crack grouting diffusion process under the one-dimensional grouting diffusion condition of the crack and the two-dimensional circular grouting diffusion condition is established, so as to realize the effective prediction of the grouting pressure and the grouting diffusion radius during the grouting diffusion process, greatly improving the prediction accuracy of the grouting diffusion process and providing a guarantee for realizing scientific grouting design in the water-rich rock mass crack environment of the tunnel.

[0046] Finally, it should be noted that any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention. Although the specific implementation manners of the present invention have been described above in conjunction with the accompanying drawings, this is not a limitation on the protection scope of the present invention. Those skilled in the art should understand that various modifications or deformations that can be made without creative efforts on the basis of the technical solutions of the present invention are still within the protection scope of the present invention.

Claims

1. A calculation method for the grouting diffusion process in the fissures of water-rich rock masses under the action of slurry-water mixing, characterized in that, Including the following steps: (1)Calculate the relationships between the widths of the slurry-water mixing zones ∆X and the grouting time t under the one-dimensional grouting diffusion condition in fractures and the two-dimensional circular grouting diffusion condition in fractures respectively; (2)Based on the assumed grouting diffusion radius under the one-dimensional grouting diffusion condition of the crack and the two-dimensional circular grouting diffusion condition of the crack R j and the relational expression in step (1), calculate the effective grouting diffusion radius R y and the maximum grouting diffusion radius R m under the above two conditions respectively, as well as the relational expression between the grouting time t ; (3) Based on the relational expression in step (1) and the R y , R m , calculate the spatial distribution equations of the cement slurry concentration inside the fracture under the one-dimensional grouting diffusion condition of the fracture and the two-dimensional circular grouting diffusion condition of the fracture respectively: W / C ( r , t ), where the r is the distance from the grouting hole, and the t is the grouting time; (4) Based on the W / C ( r , t ), respectively calculate the spatial distribution equations of the slurry rheological parameters under the one-dimensional grouting diffusion condition of the crack and the two-dimensional circular grouting diffusion condition of the crack; (5) Based on the spatial distribution equation of the slurry rheological parameters in step (4), and according to the flow control equation of Bingham fluid slurry, calculate the slurry flow control equations expressed by the grouting flow rate under the above two working conditions respectively. q The slurry flow control equation expressed; (6) Integrate the equation obtained in step (5) within the regions corresponding to the saturated slurry zone and the slurry-water mixing zone, and substitute the hydrostatic pressure boundary condition at the R m obtained maximum grouting diffusion radius to obtain the pressure spatial distribution equations within the grouting diffusion regions under the one-dimensional grouting diffusion condition in fractures and the two-dimensional circular grouting diffusion condition in fractures; (7)Respectively set the distances from the grouting holes r = 0, r = the radius of the grouting hole r 0, and obtain the respective grouting pressures at the two distances: p g0 = p ( r = 0, t ), p gr = p ( r = r 0 , t ), substitute them into the pressure spatial distribution equation in step (6), and obtain the relationship between the grouting pressure and time at the inlet under the one-dimensional grouting diffusion condition of the fracture and the two-dimensional circular grouting diffusion condition of the fracture, and that's it.

2. The calculation method for the grouting diffusion process in the fissures of water-rich rock mass under the slurry-water mixing action according to claim 1, wherein In step (1), the width of the slurry-water mixing zone ∆X and the grouting time t are calculated by the following formulas (1) and (2): （1）； （2）； Wherein: the RSR is the degree of slurry - water mixing, the RSR s is the stable value of the slurry - water mixing degree, the R j is the assumed grouting diffusion radius under the corresponding working conditions; the A and B are constants related to factors such as fracture aperture and grouting flow rate.

3. The calculation method for the grouting diffusion process in the fissures of water-rich rock masses under the action of slurry-water mixing according to claim 2, characterized in that, In the formulas (1) and (2), the assumed grouting diffusion radii under the one-dimensional grouting diffusion condition in fractures and the two-dimensional circular grouting diffusion condition in fractures R j are respectively: R j1 =qt / db, R j2 = ; where: q is the grouting flow rate, t is the grouting time, d is the fracture aperture, b is the width of the cross-sectional area of the fracture through which the fluid flows.

4. The calculation method for the grouting diffusion process in the fissures of water-rich rock mass under the slurry-water mixing action according to claim 1, wherein, In step (2), the R y , R m are respectively calculated by the following formula (3): （3）。 5. The calculation method for the grouting diffusion process in the fissures of water-rich rock mass under the slurry-water mixing action according to claim 1, characterized in that In step (3), the W / C ( r , t ) is calculated by the following formula (4), where: the W / C 0 is the initial water-cement ratio of the grouting slurry, r is the distance from the grouting hole: （4）。 6. The calculation method for the grouting diffusion process in the fissures of water-rich rock masses under the slurry-water mixing action according to claim 1, wherein In step (4), the rheological parameters of the slurry include the yield stress of the slurry τ 0, and the viscosity of the slurry μ .

7. The calculation method for the grouting diffusion process in the fissures of water-rich rock mass under the slurry-water mixing action according to claim 6, characterized in that, The yield stress of the slurry τ 0, the viscosity of the slurry μ The spatial distribution equations are calculated by the following formula (5): （5）。 8. The calculation method for the grouting diffusion process in the fissures of water-rich rock mass under the slurry-water mixing action according to claim 1, characterized in that In step (5), the flow control equation of the Bingham fluid slurry is as shown in formula (6) below; （6）； Wherein: the p is the internal grout pressure of the crack, the d is the crack aperture, the r is the distance from the grouting hole, and the τ 0 ( r , t ), μ ( r , t ) are the spatial distribution equations of the grout rheological parameters shown in Equation (5), respectively.

9. The calculation method for the grouting diffusion process in the fissures of water-rich rock mass under the action of slurry-water mixing according to claim 8, characterized in that In the formula (6), the average velocity of the grout under the one-dimensional grouting diffusion condition of the crack is calculated by the following formula: q = db ; Alternatively, the average velocity of the grout under the two-dimensional circular grouting diffusion condition in the fracture is calculated using the following formula: q = 2πrd , where d is the fracture aperture.

10. The calculation method for the grouting diffusion process in the fissures of water-rich rock masses under the action of slurry-water mixing according to any one of claims 1-9, characterized in that In step (6), the groundwater pressure under the fractured saturated water environment is taken as the hydrostatic pressure boundary condition.

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