Numerical method for simulating mechanical properties of ice rock clastic bodies with different ice contents

Abstract

The invention relates to the technical field of numerical simulation, and particularly discloses a numerical method for simulating mechanical properties of ice rock clastic bodies with different ice contents, which comprises the following steps: monitoring shear stress and angular displacement of the ice rock clastic bodies after giving the speed of a ring shear apparatus according to a ring shear apparatus model established by a three-dimensional particle flow program PFC, and meanwhile, calculating the mechanical properties of the ice rock clastic bodies according to the shear stress and angular displacement of the ice rock clastic bodies. Implicit heat transfer calculation is conducted on ice particles and rock particles on the friction interface of the upper shear box and the lower shear box, when the ice rock debris reaches the residual shear strength, calculation is stopped, a state diagram of different ice contents after shearing is completed is simulated, and finally a relational graph of the ice contents and the residual shear stress of the ice rock debris is obtained. The invention provides a comprehensive and detailed framework which is used for simulating and analyzing the mechanical properties of the ice rock clastic bodies with different ice contents, not only is beneficial to scientifically understanding the dynamic process of the ice rock clastic flow, but also can provide guidance for related engineering application.

Description

Technical Field

[0001] The invention relates to the technical field of numerical simulation, and in particular to a numerical method for simulating the mechanical properties of ice-rock debris bodies with different ice contents. Background Art

[0002] Ice-rock debris bodies are composite materials composed of ice and rock debris. During the movement of high-speed long-distance landslides, the ice in the debris changes into water due to friction. The lubrication of the ice film and water significantly reduces the friction resistance of the ice-rock mixture when sliding. Therefore, debris bodies with different ice contents show significant differences in high-speed long-distance landslides. Since ice-rock debris flows usually occur in dangerous environments, direct observation may face high safety risks.

[0003] When exploring the mechanical properties of ice-rock debris during the shear process, the explicit solution method is usually used to calculate the frictional heat generation between rocks and the heat absorption of rock particles and ice particles. That is, thermodynamic modeling is performed on a macro scale, and the energy conservation equation during the movement of ice-rock debris is established to solve the generation and dissipation of frictional heat in each time step. However, the explicit solution method cannot cope with the complex glacial environment and also has great limitations on the time step.

[0004] Therefore, in order to solve the above problems, a numerical method is needed to simulate the mechanical properties of ice-rock debris bodies with different ice contents. The method can simulate the shear performance of ice-rock debris bodies with different ice contents in a ring shear apparatus until the residual shear strength is reached, which provides an important scientific basis for understanding and predicting the behavior of ice-rock debris flows. Summary of the invention

[0005] In view of this, the purpose of the present invention is to provide a numerical method for simulating the mechanical properties of ice-rock debris bodies with different ice contents, which can simulate the shear performance of ice-rock debris bodies with different ice contents in a ring shear apparatus until the residual shear strength is reached, providing an important scientific basis for understanding and predicting the behavior of ice-rock debris flows.

[0006] The present invention provides a numerical method for simulating the mechanical properties of ice-rock debris bodies with different ice contents. First, a ring shear instrument model is established by using a PFC discrete element method, in which an upper shear box remains stationary and a lower shear box rotates at a specified rate. The mechanical characteristics of ice-rock debris bodies with different ice contents in a shearing process are simulated according to the ring shear instrument model until the ice-rock debris bodies reach a residual shear strength. The method comprises the following steps:

[0007] S11: after starting and initializing, a ring shear instrument model with different ice contents in the upper shear box is established, and the initial temperature of the particles is set;

[0008] S12: Based on the model established in S11, the speed of the ring shear instrument is set to monitor the shear stress and angular displacement of the rock particles in the shear plane;

[0009] S13: Calculate the friction heat between the upper and lower rock particles in the shear plane based on the shear stress and angular displacement determined in S12;

[0010] S14: Determine whether the contact type between the particles is rock particles and ice particles; if yes, proceed to S15; if no, proceed directly to S16;

[0011] S15: Calculate the thermal conductivity between rock particles and ice particles based on the particle contact information;

[0012] S16: Calculate the heat flux into rock particles and ice particles based on Fourier's law;

[0013] S17: Establish heat conduction equation and calculate particle temperature;

[0014] S18: judging whether the ice-rock debris body reaches the residual shear strength, if not, returning to S13;

[0015] S19: Obtain the relationship between ice content and residual shear stress of the final ice rock debris body.

[0016] As a further improvement of the above technical solution, in a ring shear instrument model in which the upper shear box remains stationary and the lower shear box rotates at a specified rate, rock particles are represented by spherical particles, ice particles are represented by flexible clusters, normal stress is applied, and the contact information and initial temperature of the rock particles and ice particles are set.

[0017] As a further improvement to the above technical solution, in step S12, based on the established ring shear instrument model, the lower shear box is sheared at a specified rate; the shear stress and angular displacement of the rock particles of the ice rock debris body are monitored;

[0018] The shear stress on the rock particles of the glacial rock debris is:

[0019]

[0020] Among them, M is the moment exerted on rock particles in the glacial rock debris body, D is the radius of the outer ring, and d is the radius of the inner ring.

[0021] The angular displacement of rock particles in the glacial rock debris body is:

[0022] S=R m θ;

[0023] Among them, R m is the radius of the rock particles in the ice rock debris body in the model, and θ is the arc of rotation of the rock particles when the ring shear instrument rotates.

[0024] As a further improvement to the above technical solution, in step S13, the friction heat generated between the upper and lower rock particles is:

[0025] Q = τS;

[0026] Among them, τ is the shear stress on the rock particles of the glacial rock debris body, and S is the angular displacement of the rock particles.

[0027] As a further improvement to the above technical solution, in step S15, the thermal conductivity between the rock particles and the ice particles is:

[0028]

[0029] Among them, r represents rock particles, i represents ice particles, and k i is the thermal conductivity of ice particles, k r is the thermal conductivity of rock particles.

[0030] As a further improvement to the above technical solution, in step S16, the process of calculating the heat flux flowing into the ice particles and the rock particles includes:

[0031] Based on the particle temperature information, it follows the principle that rock particles with higher temperatures transfer heat to adjacent rock particles and ice particles with lower temperatures;

[0032] In the process of heat transfer, heat transfer between rock particles and rock particles and between rock particles and ice particles occurs simultaneously;

[0033] The heat flux of the hot rock particles flowing into the cold rock particles is:

[0034]

[0035] Where α is the geometric correction factor, is the width of the cross section formed by adjacent rock particles, is the distance between the centers of adjacent rock particles, is the temperature of the rock particle with higher temperature among adjacent rock particles, T r The temperature of the rock grains where the temperature of the adjacent rock grains is lower;

[0036] The heat flux from the rock particles into the ice particles is:

[0037]

[0038] Among them, S ir is the width of the cross section formed by adjacent ice particles and rock particles, L ir is the distance between the centers of adjacent ice particles and rock particles, T i and T rare the temperatures of ice particles and rock particles, respectively.

[0039] As a further improvement to the above technical solution, in step S17, the process of calculating the particle temperature includes:

[0040] calculating the temperatures of the ice and rock particles based on the heat flux flowing into the ice and rock particles;

[0041] The temperature of the rock particles is:

[0042]

[0043] in, is the temperature of the rock particles in the previous time step, C r is the specific heat capacity of rock particles, M r is the mass of rock particles;

[0044] The temperature of the ice particles is:

[0045]

[0046] in, is the temperature of the ice particle in the previous time step, C i is the specific heat capacity of ice particles, M i is the mass of the ice particles.

[0047] As a further improvement to the above technical solution, in step S18, the process of judging whether the ice-rock debris body reaches the residual shear strength includes:

[0048] Based on the monitored shear stress and angular displacement, a relationship curve is determined;

[0049] Based on its relationship curve, the residual shear strength is the final stable value reached by the shear stress;

[0050] The residual shear strength of the ice-rock debris is:

[0051]

[0052] Among them, η is the viscosity coefficient, γ is the shear strain rate, σ is the normal stress, is the internal friction angle, and c is the cohesion.

[0053] As a further improvement to the above technical solution, in step S19, the process of generating a relationship diagram between ice content and residual shear strength includes:

[0054] After the simulation stops, the residual shear strength of the ice-rock debris body is output;

[0055] A relationship diagram is generated based on the residual shear strength corresponding to different ice contents.

[0056] Compared with the prior art, the present invention has the following beneficial technical effects:

[0057] The present invention provides a numerical method for simulating the mechanical properties of ice-rock debris bodies with different ice contents, which can simulate the shear performance of ice-rock debris bodies with different ice contents in a ring shear apparatus until the residual shear strength is reached, providing an important scientific basis for understanding and predicting the behavior of ice-rock debris flows.

[0058] Specifically, the present invention extends traditional mechanical simulation to the field of thermodynamics, especially to special composite materials such as ice-rock debris. By combining the PFC discrete element method with the principles of thermodynamics, the mechanical behavior of ice-rock debris at different ice contents is simulated. This combination provides a more comprehensive perspective to study the shear properties of ice-rock debris. The present invention uses numerical simulation to accurately control experimental conditions in a virtual environment, such as ice content, ring shear instrument speed, etc., which are difficult to achieve in physical experiments, thereby improving the controllability and repeatability of the experiment. Numerical simulation allows users to intuitively observe the flow of ice-rock debris at different ice contents during the shear process and the formation of shear bands, which is very helpful for understanding the internal behavior of the material. Compared with traditional physical experiments, the present invention The numerical simulation can view the results in real time, and the experimental parameters can be quickly adjusted as needed, thereby saving experimental time and reducing experimental costs; the present invention can simulate the dynamic process of ice-rock debris reaching residual shear strength, which is of great significance for predicting and analyzing the stability and danger of ice-rock debris flows; through implicit heat transfer calculations, the present invention can accurately simulate the transfer path and efficiency of thermal energy, update the thermal conduction characteristics of the contact points between ice particles and rock particles in real time, and adapt to the dynamic changes in the contact state between particles; the present invention comprehensively considers multiple physical parameters such as shear stress, angular displacement, thermal conductivity, heat flux, etc., so that the simulation results are more accurate and reliable; the relationship diagram between ice content and residual shear strength finally generated provides an intuitive reference basis for engineering design and disaster prevention.

[0059] Advantages of additional aspects of the present invention will be given in part in the following description, and in part will become obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their description are used to explain the present invention but do not constitute a limitation of the present invention.

[0061] Figure 1 This is a shearing flow chart of the ring shearing instrument for ice-rock debris with different ice contents of the present invention;

[0062] Figure 2 The temperature distribution diagram of the ice-rock debris body sheared in the present invention;

[0063] Figure 3 is a schematic diagram of the shear stress-angular displacement relationship of different ice contents of the present invention;

[0064] Figure 4 It is a schematic diagram of the relationship between ice content and residual shear strength of the present invention. DETAILED DESCRIPTION

[0065] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0066] As a background, let's first explain PFC (Particle Flow Code).

[0067] The three-dimensional particle flow program PFC (Particle Flow Code) is a particle flow simulation software based on the discrete element method DEM (Discrete Element Method). The medium materials studied are mainly divided into bulk materials and bonded materials. It is suitable for studying the macro-micro mechanical properties of materials, the deformation and flow failure process of particle aggregates, the fracture and fracture propagation of solid materials (rock blocks, etc.), etc. It can simultaneously consider complex mechanical conditions such as deformation and dynamic loads; at the same time, PFC allows detailed simulation at the particle level, can consider the behavior and interaction of each particle, and integrate with the heat conduction model to accurately describe the movement and mechanical properties of ice-rock debris flows.

[0068] PFC is a series of discrete element programs used to simulate the behavior of granular materials; it includes 2D and 3D versions, for two-dimensional and three-dimensional simulations respectively; PFC 3D It is the three-dimensional version of PFC, which is specially used to simulate particle systems in three-dimensional space, such as rocks, soils, granular materials, etc. It can simulate the movement and interaction between spherical particles, and create large particles of arbitrary shapes by "attaching" two or more small particles. These "connected" "groups of particles" can be studied as independent particles. 3D The fracture problem of solids can be simulated. The particle aggregate obtained by "bonding" adjacent particles can be used as a "solid" with elastic properties. When the "bond" between particles is gradually destroyed, the solid will produce "fracture". This embodiment uses PFC 3D The simulation performed.

[0069] This embodiment provides a numerical method for simulating the mechanical properties of ice-rock debris bodies with different ice contents. After collecting relevant actual data, a ring shear instrument model is first established by the PFC discrete element method, in which the upper shear box remains stationary and the lower shear box rotates at a specified rate; the mechanical characteristics of ice-rock debris bodies with different ice contents during shearing are simulated according to the ring shear instrument model until the ice-rock debris bodies reach residual shear strength; Figure 1 As shown, it may specifically include the following steps S11 to S19:

[0070] S11: after starting and initializing, a ring shear instrument model with different ice contents in the upper shear box is established, and the initial temperature of the particles is set;

[0071] S12: Based on the model established in S11, the speed of the ring shear instrument is set to monitor the shear stress and angular displacement of the rock particles in the shear plane;

[0072] S13: Calculate the friction heat between the upper and lower rock particles in the shear plane based on the shear stress and angular displacement determined in S12;

[0073] S14: Determine whether the contact type between the particles is rock particles and ice particles; if yes, proceed to S15; if no, proceed directly to S16;

[0074] S15: Calculate the thermal conductivity between rock particles and ice particles based on the particle contact information;

[0075] S16: Calculate the heat flux into rock particles and ice particles based on Fourier's law;

[0076] S17: Establish heat conduction equation and calculate particle temperature;

[0077] S18: judging whether the ice-rock debris body reaches the residual shear strength, if not, returning to S13;

[0078] S19: Obtain the relationship between ice content and residual shear stress of the final ice rock debris body.

[0079] The ring shear instrument can simulate the shear behavior of ice-rock debris flow at different ice contents in a controlled environment. By numerically simulating the ring shear experiment and precisely controlling the experimental conditions in a virtual environment, the flow of ice-rock debris with different ice contents during the shear process and the formation of shear bands can be intuitively observed. In addition, the numerical simulation can instantly view the results and quickly adjust the experimental parameters as needed, which can save experimental time and reduce experimental costs.

[0080] The implicit heat conduction method between particles by identifying contact can accurately detect the heat absorption and release process of each particle, more accurately simulate the transfer path and efficiency of heat energy, update the thermal conduction characteristics of the contact points between ice particles and rock particles in real time, and adapt to the dynamic changes in the contact state between particles.

[0081] The physical parameters involved in the calculation include: shear stress on rock particles in the ice-rock debris body, thermal conductivity between ice particles and rock particles, heat flux flowing into rock particles and ice particles, angular displacement, ring shear instrument speed, and particle temperature. These are important factors affecting the mechanical properties of ice-rock debris bodies. By monitoring the changes in these parameters, we can better understand the behavior of materials during shearing.

[0082] In PFC, ball particles simulate round rigid particles and are the most basic particle units used to create models of granular materials; flexible clusters are a more advanced particle unit that can simulate non-rigid particles, i.e. flexible particles; clusters are composed of multiple balls and can simulate irregularly shaped rigid or flexible particles. It is very appropriate to use clusters and balls to simulate ice particles and rock particles in ice-rock debris bodies; clusters can be used to simulate flexible ice particles, while balls can be used to represent rigid rock particles; in this way, the interaction between ice and rock and their mechanical behavior during shear can be captured more accurately.

[0083] The code of the ring shear instrument model of ice-rock debris with different ice contents is generated according to the input of the three-dimensional particle flow program PFC. The ring shear instrument is divided into an upper and a lower shear box; the upper shear box remains stationary and is an ice-rock debris body mixed with flexible clusters (cluster) and ball particles (ball); the lower shear box rotates at a set speed to be rock particles with only balls, and contact is applied between particles. At the same time, the top surface of the upper shear box of the ring shear instrument is applied with normal stress along the z-axis, and the speed of the ring shear instrument is given, so that the ring shear instrument starts shearing at the contact surface of the upper and lower shear boxes when it starts to rotate.

[0084] The upper shear box is composed of ice-rock debris, and the lower shear box is composed of rock particles, which simulates the sliding of ice-rock debris on a rock-containing landslide. The expression of normal stress is as follows:

[0085] σ=γh (1)

[0086] Where Y is the mixed bulk density of the glacial rock debris body, and h is the thickness of the glacial rock debris body on the landslide.

[0087] During the rotation of the ring shear instrument, the relationship between the shear stress and angular displacement of ice particles in the ice-rock debris body is monitored to determine whether the rock particles in the ice-rock debris body have reached the residual shear strength. The shear stress of the rock particles is:

[0088]

[0089] Among them, M is the moment exerted on rock particles in the glacial rock debris body, D is the radius of the outer ring, and d is the radius of the inner ring.

[0090] The angular displacement of rock particles during shearing is:

[0091] S=R m θ (3)

[0092] Among them, R m is the radius of the rock particles in the ice rock debris body in the model, and θ is the arc of rotation of the rock particles when the ring shear instrument rotates.

[0093] During the rotation of the lower shear box of the ring shear instrument, the rock particles in the ice-rock debris body of the upper shear box and the rock particles in the lower shear box generate heat due to friction. The heat value generated is:

[0094] Q=τS (4)

[0095] Where τ is the shear stress on the rock particles in the lower shear box, and S is the angular displacement of the rock particles.

[0096] A heat conduction model is established based on Fourier's law to calculate the heat transfer between particles. The relationship between the heat flux per unit area q and the temperature gradient ΔT in Fourier's law is:

[0097] q=-kΔT (5)

[0098] Where q is the heat flux, k is the thermal conductivity, and ΔT is the temperature gradient.

[0099] Because the wall of the ring shear instrument is smooth and frictionless, heat is only generated between rock particles during the shearing process. The rock particles on the shear surface increase in temperature due to friction, and the heat generated is transferred to the adjacent rock particles and ice particles. If the heat generated by the particles in the model is Q, the temperature increase of the rock particles during the friction process can be calculated as:

[0100]

[0101] Where Q is the heat generated by friction, t is the time, M is the mass of the particle, and C is the specific heat capacity.

[0102] During the shearing process of ice-rock debris, heat is assumed to be conducted through a virtual uniform rectangular channel between two particles. After the temperature of the rock particles that generate friction increases, heat is transferred simultaneously between the adjacent rock particles and ice particles. The transfer type is determined by the contact information of the particles. When the contact is between rock particles and the temperatures are different, the heat flux transferred from the rock particles with high temperature to the rock particles with low temperature is:

[0103]

[0104] The subscript r represents rock particles, a r is the geometric correction factor, k r is the thermal conductivity of rock particles, is the width of the cross section formed by adjacent rock particles, is the distance between the centers of adjacent rock particles, is the temperature of the rock particle with higher temperature among adjacent rock particles, T r The temperature of a rock grain whose adjacent rock grain has a lower temperature.

[0105] Cross-sectional width formed by adjacent rock particles for

[0106]

[0107] Among them, R r is the rock particle radius.

[0108] When the contact is between rock particles and ice particles, the heat flux transferred from the rock particles to the adjacent ice particles is:

[0109]

[0110] Where i represents ice particles, a i is the geometric correction factor, S ir is the width of the cross section formed by adjacent ice particles and rock particles, L ir is the distance between the centers of adjacent ice particles and rock particles, T i and T r are the temperatures of ice particles and rock particles, respectively, k ir is the thermal conductivity between rock particles and ice particles.

[0111] Adjacent ice particles and rock particles form a cross-sectional width S ir for

[0112] S ir =R i +R r (10)

[0113] Among them, R iis the radius of the ice particle.

[0114] The thermal conductivity between rock particles and ice particles is:

[0115]

[0116] Among them, k i is the thermal conductivity of ice particles.

[0117] Geometric correction factor a j The expression is:

[0118]

[0119] Among them, j is r or i, that is, is the volume fraction of rock particles in the model, is the volume fraction of ice particles in the model, CN r is the average number of neighbors of rock particles, CN i is the average number of neighbors of an ice particle.

[0120] Volume fraction of rock particles or ice particles in the model for:

[0121]

[0122] in, is the side length of the circumscribed polygon of the rock or ice particle, R j is the radius of the rock or ice particle.

[0123] During the rotation of the ring shear instrument, the number of rock particles with higher temperature adjacent to the rock particle r in the model is n, and the heat flux flowing into the rock particle r is:

[0124]

[0125] in, is the width of the cross section formed by adjacent rock particles, is the distance between the centers of adjacent rock particles, is the temperature of the rock particle with higher temperature among adjacent rock particles, T r The temperature of a rock grain whose adjacent rock grain has a lower temperature.

[0126] Similarly, during the shear process, the number of rocks near an ice particle i in the model is p, and the heat flux flowing into the ice particle i is:

[0127]

[0128] Substituting equations (13) and (14) into equation (5), the temperature changes of rock particles and ice particles are:

[0129]

[0130] in, is the temperature of the rock particles in the previous time step, C r is the specific heat capacity of rock particles, M r is the mass of rock particles.

[0131]

[0132] in, is the temperature of the ice particle in the previous time step, C i is the specific heat capacity of ice particles, M i is the mass of the ice particles.

[0133] During the rotation of the ring shear instrument, the shear stress on the ice-rock debris gradually decreases until it stabilizes due to the frictional heat generated by the shear surface. The final stable value of the angular stress-shear stress curve of the rock particles in the ice-rock debris is the residual shear strength, which is expressed as:

[0134]

[0135] Among them, η is the viscosity coefficient, γ is the shear strain rate, σ is the normal stress, is the internal friction angle, and c is the cohesion.

[0136] The shear strain rate γ is:

[0137]

[0138] Among them, d and D are the inner and outer diameters of the ring shear instrument, ω is the angular velocity of the ring shear instrument, and H is the height of the ice-rock debris body.

[0139] When the residual shear strength is reached, the ring shear instrument stops rotating, and the temperature distribution state diagram of the ice-rock debris body after shearing is completed is generated according to formulas (16) and (17), and finally the relationship diagram between its ice content and residual shear strength is obtained, as shown in Figure 4 shown.

[0140] Finally, it should be noted that this article uses specific examples to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only to help understand the core idea of ​​the present invention. Without departing from the principles of the present invention, the present invention may also be improved and modified, and these improvements and modifications also fall within the scope of protection of the present invention.

Claims

1. A numerical method for simulating the mechanical properties of ice-rock debris bodies with different ice contents, characterized in that: Firstly, a ring shear instrument model is established by PFC discrete element method, in which the upper shear box remains stationary and the lower shear box rotates at a specified rate; the mechanical characteristics of ice-rock debris with different ice contents in the shear process are simulated according to the ring shear instrument model until the ice-rock debris reaches the residual shear strength, which includes the following steps: S11: after starting and initializing, a ring shear instrument model with different ice contents in the upper shear box is established, and the initial temperature of the particles is set; S12: Based on the model established in S11, the speed of the ring shear instrument is set to monitor the shear stress and angular displacement of the rock particles in the shear plane; S13: Calculate the friction heat between the upper and lower rock particles in the shear plane based on the shear stress and angular displacement determined in S12; S14: Determine whether the contact type between the particles is rock particles and ice particles; if yes, proceed to S15; if no, proceed directly to S16; S15: Calculate the thermal conductivity between rock particles and ice particles based on the particle contact information; S16: Calculate the heat flux into rock particles and ice particles based on Fourier's law; S17: Establish heat conduction equation and calculate particle temperature; S18: judging whether the ice-rock debris body reaches the residual shear strength, if not, returning to S13; S19: Obtain the relationship between ice content and residual shear stress of the final ice rock debris body.

2. A numerical method for simulating mechanical properties of ice-rock debris bodies with different ice contents according to claim 1, characterized in that: In the ring shear instrument model, the upper shear box remains stationary and the lower shear box rotates at a specified rate. Rock particles are represented by spherical particles, ice particles are represented by flexible clusters, normal stress is applied, and the contact information and initial temperature of rock particles and ice particles are set.

3. A numerical method for simulating mechanical properties of ice-rock debris bodies with different ice contents according to claim 1, characterized in that: In step S12, based on the established ring shear instrument model, the lower shear box is sheared at a specified rate; the shear stress and angular displacement of the rock particles of the ice rock debris body are monitored; The shear stress on the rock particles of the glacial rock debris is: Among them, M is the moment exerted on rock particles in the glacial rock debris body, D is the radius of the outer ring, and d is the radius of the inner ring. The angular displacement of the rock particles in the glacial rock debris body is: S=R m I; Among them, R m is the radius of the rock particles in the ice rock debris body in the model, and θ is the arc of rotation of the rock particles when the ring shear instrument rotates.

4. A numerical method for simulating mechanical properties of ice-rock debris bodies with different ice contents according to claim 1, characterized in that: In step S13, the friction heat generated between the upper and lower rock particles is: Q = τS; Among them, τ is the shear stress on the rock particles of the glacial rock debris body, and S is the angular displacement of the rock particles.

5. A numerical method for simulating mechanical properties of ice-rock debris bodies with different ice contents according to claim 1, characterized in that: In step S15, the thermal conductivity between rock particles and ice particles is: Among them, r represents rock particles, i represents ice particles, and k i is the thermal conductivity of ice particles, k r is the thermal conductivity of rock particles.

6. A numerical method for simulating mechanical properties of ice-rock debris bodies with different ice contents according to claim 1, characterized in that: In step S16, the process of calculating the heat flux flowing into the ice particles and the rock particles includes: Based on the particle temperature information, it follows the principle that rock particles with higher temperatures transfer heat to adjacent rock particles and ice particles with lower temperatures; In the process of heat transfer, heat transfer between rock particles and rock particles and between rock particles and ice particles occurs simultaneously; The heat flux of the hot rock particles flowing into the cold rock particles is: Where α is the geometric correction factor, is the width of the cross section formed by adjacent rock particles, is the distance between the centers of adjacent rock particles, is the temperature of the rock particle with higher temperature among adjacent rock particles, T r The temperature of the rock grains where the temperature of the adjacent rock grains is lower; The heat flux from the rock particles into the ice particles is: Among them, S ir is the width of the cross section formed by adjacent ice particles and rock particles, L ir is the distance between the centers of adjacent ice particles and rock particles, T i and T r are the temperatures of ice particles and rock particles, respectively.

7. A numerical method for simulating mechanical properties of ice-rock debris bodies with different ice contents according to claim 1, characterized in that: In step S17, the process of calculating the particle temperature includes: calculating the temperatures of the ice and rock particles based on the heat flux flowing into the ice and rock particles; The temperature of the rock particles is: in, is the temperature of the rock particles in the previous time step, C r is the specific heat capacity of rock particles, M r is the mass of rock particles; The temperature of the ice particles is: in, is the temperature of the ice particle in the previous time step, C i is the specific heat capacity of ice particles, M i is the mass of the ice particles.

8. A numerical method for simulating mechanical properties of ice-rock debris bodies with different ice contents according to claim 1, characterized in that: In step S18, the process of judging whether the ice-rock debris body reaches the residual shear strength includes: Based on the monitored shear stress and angular displacement, a relationship curve is determined; Based on its relationship curve, the residual shear strength is the final stable value reached by the shear stress; The residual shear strength of the ice-rock debris is: Among them, η is the viscosity coefficient, γ is the shear strain rate, σ is the normal stress, is the internal friction angle, and c is the cohesion.

9. A numerical method for simulating mechanical properties of ice-rock debris bodies with different ice contents according to claim 1, characterized in that: In step S19, the process of generating a relationship diagram between ice content and residual shear strength includes: After the simulation stops, the residual shear strength of the ice-rock debris body is output; A relationship diagram is generated based on the residual shear strength corresponding to different ice contents.

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