A mountainous highway spoil site instability risk zoning evaluation method

Abstract

The application discloses a mountainous highway abandoned slag field instability risk zoning evaluation method, comprising the following steps: establishing a slope model, and dividing the instability process of the mountainous highway abandoned slag slope into stages; respectively establishing the force balance equation of each stage; obtaining the movement distance equation of the abandoned slag sliding body along the ground by using the kinetic energy friction dissipation balance equation; when the sliding friction coefficient of the sliding body and the sliding surface and the sliding friction coefficient of the sliding body and the ground are consistent, respectively taking the maximum value and the minimum value of the sliding friction coefficient to substitute into the movement distance equation of the abandoned slag sliding body along the ground, and obtaining the minimum movement distance and the maximum movement distance of the abandoned slag sliding body along the ground; according to the minimum movement distance and the maximum movement distance of the abandoned slag sliding body along the ground, the high, medium and low danger zoning of the instability risk threat of the abandoned slag slope is carried out; the application is based on the actual abandoned slag project, is carried out under the same force balance relationship, movement equation and energy equation, is simple and easy to implement from calculation to zoning, and has strong operability.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of geotechnical engineering, and more particularly relates to a mountainous highway spoil site instability risk zoning evaluation method. BACKGROUND

[0002] In recent years, the construction of traffic engineering in mountainous areas has gradually increased, and the environmental protection pressure brought by earthwork balance has increased sharply. According to the new regulations, who builds who manages, the spoil site of the traffic engineering in mountainous areas is no longer handed over to the local government after being built, and the safety influence of the spoil site near the existing building and structure is highly valued by all parties. However, the existing laws and regulations and the soil and water conservation specifications are executed according to the relevant requirements of geological disasters, which does not reflect the characteristics of the industry and does not have related quantitative method support. The current common practice is to use the simple potential energy kinetic energy conversion energy formula in physics to evaluate, and the formula does not reflect the difference between the static friction performance and the sliding friction performance of the soil and stone mixed spoil, and there is an evaluation error. The rate effect of the spoil material is not enough to support the related calculation, and most of them are experience values. The superposition of parameter and formula errors causes a large gap between the evaluation and the actual situation. In addition, the traditional combination calculation uses different equations to obtain different distances, forms a zoning standard, and the color marking and zoning standard of different zoning results are not uniform, which has a certain randomness and is not conducive to the authority and comparability of the evaluation conclusion. Therefore, it is urgent to propose a zoning evaluation method and index system for the instability risk evaluation of the soil and stone mixed spoil slope, to standardize and quantify the related work under the same method, and to improve the instability risk evaluation efficiency of the spoil engineering under the complex surrounding environment. SUMMARY

[0003] In view of the above defects or improvement needs of the prior art, the present application provides a mountainous highway spoil site instability risk zoning evaluation method, which simulates the instability motion mechanism of the spoil slope, analyzes the instability process of the actual spoil slope, and constructs a mountainous highway spoil slope sliding motion equation considering the rate effect of the friction performance; the motion equation is used to derive the spoil slope instability motion distance formula, and a mountainous highway spoil site instability risk zoning evaluation method and index system are constructed; the problems that the traditional spoil slope instability risk evaluation method uses different equations to obtain different distances, and the color marking and zoning standard of different zoning results are not uniform, which has a certain randomness and is not conducive to the authority and comparability of the evaluation conclusion can be solved.

[0004] In order to achieve the above purpose, the present application provides a mountainous highway spoil site instability risk zoning evaluation method, which is characterized by the following steps:

[0005] S1: establishing a slope model, simulating the instability motion mechanism of the spoil slope, and dividing the instability process of the mountainous highway spoil slope into stages in combination with the instability process of the actual spoil slope;

[0006] S2: establishing force balance equations of each stage in step S1;

[0007] S3: on the basis of the force balance equations established in step S2, kinetic energy friction dissipation balance equations are used to obtain a movement distance equation of the slag sliding body along the ground;

[0008] S4: when the sliding friction coefficient along the sliding surface does not consider the saturation factor of the coarse-grained soil and the sliding friction coefficient along the ground does not consider the ratio of the pore water pressure of the coarse-grained soil, the sliding friction coefficient of the sliding body and the sliding surface and the sliding friction coefficient of the sliding body and the ground are consistent, the maximum value and the minimum value of the sliding friction coefficient are respectively substituted into the movement distance equation of the slag sliding body along the ground obtained in step S3 to obtain the minimum movement distance and the maximum movement distance of the slag sliding body along the ground;

[0009] S5: according to the minimum movement distance and the maximum movement distance of the slag sliding body along the ground, the slag slope instability risk threat is divided into high-risk, medium-risk and low-risk zones, and different colors are used to represent them.

[0010] Further, in step S5, the high-risk zone is from the minimum movement distance of the sliding body sliding on the ground to the maximum movement distance, represented by red; the medium-risk zone is from the minimum movement distance of the sliding body sliding on the ground to the maximum movement distance, represented by yellow; and the low-risk zone is beyond the maximum movement distance of the sliding body sliding on the ground, represented by green.

[0011] Further, in step S1, the instability process of the slag slope of the mountainous highway is divided into stages, including an initial limit equilibrium stage, a slope surface starting and accelerating sliding and sliding to the slope foot stage, and a ground decelerating sliding until stopping stage.

[0012] The force balance equation in step S2 includes the force balance equation of the slag slope sliding body along the sliding surface in the initial limit equilibrium stage, the force balance equation of the slag slope sliding body in the accelerated sliding stage with the sliding force greater than the anti-sliding force, and the force balance equation of the slag slope sliding body in the decelerating sliding stage with the friction resistance greater than the sliding force.

[0013] Further, the force balance equation of the slag slope along the sliding surface in step S2 includes

[0014] T1=F0 (1)

[0015] T1=G sin j1 (2)

[0016] N1=G cos j1 (3)

[0017] F0=CL1+G cos j1μ1(0) (4)

[0018] F0= G cos j1 μ1(0) (4)

[0019] Further, the force balance equation of the acceleration of the discarded slope sliding body in step S2 along the sliding surface is greater than the anti-sliding force, including

[0020] R1= T1- F1 (5)

[0021] T1= G sin j1 (6)

[0022] N1= G cos j1 (7)

[0023] F1= G cos j1 μ1(v1) (8)

[0024] wherein R1 is the remaining sliding force of the sliding body on the sliding surface; F1 is the sliding friction of the sliding body gravity G along the normal force N1 of the sliding surface; μ1 is the sliding friction coefficient of the sliding body and the sliding surface; v1 is the sliding speed of the sliding body along the sliding surface; μ1 is negatively correlated with the sliding speed v1 of the sliding body along the sliding surface.

[0025] Further, the maximum speed of the sliding body moving to the slope foot is calculated by formula (9):

[0026] v 1max = at (9)

[0027] wherein a is the acceleration of the sliding body under the action of the remaining sliding force; t is the time of the sliding body moving to the slope foot; v 1max is the maximum speed of the sliding body moving to the slope foot.

[0028] The remaining sliding force R1 of the sliding body on the sliding surface can also be calculated by formula (10):

[0029] R1= ma (10)

[0030] wherein m is the mass of the sliding body.

[0031] Further, the acceleration a of the sliding body under the action of the remaining sliding force is calculated by formula (11):

[0032] a= g sin j1- g cos j1μ1(v1) (11)

[0033] wherein g is the acceleration of gravity, and the value is 9.8 m / s 2 .

[0034] The relationship between the centroid height h of the sliding body, the acceleration a of the sliding body under the action of the residual sliding force, the time t of the sliding body moving to the slope foot, and the angle j1 between the sliding surface and the horizontal plane is represented by equation (12):

[0035]

[0036] The maximum speed v1 of the sliding body moving to the slope foot can also be represented by equation (13):

[0037]

[0038] Further, the force balance equation of the waste rock slope sliding body decelerating sliding along the ground in step S2 is represented by equation (14):

[0039] R2 = F2 - T2 (14)

[0040] T2 = G sin j2 (15)

[0041] N2 = G cos j2 (16)

[0042] F2 = G cos j2 μ2 (v2) (17)

[0043] In the equation, R2 is the residual friction of the sliding body on the ground; F2 is the friction generated by the normal component of the gravity G of the sliding body along the ground; T2 is the sliding force generated by the tangential component of the gravity G of the sliding body along the ground; N2 is the normal component of the gravity G of the sliding body along the ground; μ2 is the sliding friction coefficient between the sliding body and the ground; v2 is the sliding speed of the sliding body along the ground; μ2 is negatively correlated with the sliding speed v2 of the sliding body along the ground; and j2 is the inclination angle of the ground.

[0044] Further, the kinetic energy friction dissipation balance equation of step S3 is represented by equation (18):

[0045]

[0046] In the equation, L2 is the sliding distance of the sliding body on the ground; v 1max is the maximum speed of the sliding body moving to the slope foot.

[0047] Further, the motion distance equation of the waste rock sliding body along the ground in step S3 is represented by equation (19):

[0048]

[0049] In the equation, L2 is the sliding distance of the sliding body on the ground.

[0050] Overall, the above technical solutions conceived by the present application can achieve the following beneficial effects compared with the prior art:

[0051] (1) The mountainous highway spoil site instability risk zoning evaluation method of the present application, through simulating the instability movement mechanism of the spoil slope, combining with the instability process analysis of the actual spoil slope, constructs the sliding movement equation of the mountainous highway spoil slope considering the rate effect of friction performance; the movement equation is used to deduce the instability movement distance formula of the spoil slope, and the instability risk zoning evaluation method and index system of the mountainous highway spoil site are constructed; compared with the traditional spoil slope instability risk evaluation, the method adopted by the present application is simple and clear in physical and mechanical mechanism based on the actual spoil engineering; the instability risk zoning evaluation of the spoil site of the mountainous traffic engineering is carried out under the same movement equation and energy equation, which is different from the combined calculation of the existing method; the parameters and methods involved are unified in the same force balance and energy conservation relationship, which is more in line with the actual spoil instability process; in addition, the traditional instability risk evaluation is only related to the height of the spoil slope, and the movement friction coefficient is a statistical empirical value; the spoil slope instability risk zoning evaluation method of the present application is not only related to the height, but also related to the sliding surface slope, ground slope, sliding friction coefficient along the sliding surface, sliding friction coefficient along the ground, etc., which is more in line with the mechanical mechanism, stage characteristics and movement characteristics of spoil instability, and the zoning has certain conservative characteristics and strong operability; the mountainous highway spoil site instability risk zoning evaluation method of the present application can provide guidance for the spoil slope instability risk evaluation in mountainous areas.

[0052] (2) The mountainous highway spoil site instability risk zoning evaluation method of the present application is more in line with the physical and mechanical mechanism of spoil instability, the sliding surface is the fracture surface determined by the active fracture angle; the stage division is more in line with the several stages of the actual spoil slope instability process; the sliding friction coefficient along the sliding surface does not consider the saturation factor of coarse-grained soil, and the sliding friction coefficient along the ground does not consider the pore water pressure ratio of coarse-grained soil, the minimum movement distance and the maximum movement distance are estimated, the dangerous range circled by the two has certain conservative characteristics, different colors are used for zoning, and the use standard of the country for color is met; the spoil site instability risk zoning evaluation method of the present application is simple and easy to operate from calculation to zoning, and has strong operability, the related parameters can be obtained through specified experiment test, and the evaluation result is practical and feasible for the safety control of actual engineering.

[0053] (3) The mountainous highway spoil site instability risk zoning evaluation method of the present application has the characteristic curve of the material static and sliding friction performance evolution law to provide calculation parameter support, can take the maximum value and the minimum value for estimation, or can take more accurate movement distance through dynamic parameter integral, has certain universality; tracking evaluation and parameter accumulation are beneficial to the formation of regional big data, and compared with the traditional regional experience value, the spoil site instability risk evaluation of the present application has more guidance. BRIEF DESCRIPTION OF DRAWINGS

[0054] Figure 1 The flowchart of the mountainous highway spoil site instability risk zoning evaluation method of the present application is shown in the figure;

[0055] Figure 2 A schematic diagram of initial topographic structure of discarded slag for a mountainous highway discarded slag site instability risk zoning evaluation method of an embodiment of the present application;

[0056] Figure 3 A schematic diagram of discarded slag sliding body movement process for a mountainous highway discarded slag site instability risk zoning evaluation method of an embodiment of the present application;

[0057] Figure 4 A schematic diagram of discarded slag sliding body after re-accumulation and stabilization for a mountainous highway discarded slag site instability risk zoning evaluation method of an embodiment of the present application;

[0058] Figure 5 A schematic diagram of discarded slag sliding body movement and force on the sliding surface for a mountainous highway discarded slag site instability risk zoning evaluation method of an embodiment of the present application-initial limit equilibrium stage (i1 is the slope in the figure);

[0059] Figure 6 A schematic diagram of discarded slag sliding body movement and force on the sliding surface for a mountainous highway discarded slag site instability risk zoning evaluation method of an embodiment of the present application-slope surface starting and accelerating sliding and sliding down to the slope foot stage (i1 is the slope in the figure);

[0060] Figure 7 A schematic diagram of discarded slag sliding body movement and force on the ground for a mountainous highway discarded slag site instability risk zoning evaluation method of an embodiment of the present application-ground deceleration sliding until stopping stage (i2 is the ground inclination angle);

[0061] Figure 8 A schematic diagram of the relationship curve between the static and dynamic friction coefficients and the speed of the discarded slag sliding body for a mountainous highway discarded slag site instability risk zoning evaluation method of an embodiment of the present application. DETAILED DESCRIPTION

[0062] In order to make the purpose, technical scheme and advantages of the present application clearer and more apparent, the present application will be further described in detail below in combination with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and do not limit the present application. In addition, the technical features involved in each embodiment of the present application described below can be combined with each other as long as they do not conflict with each other.

[0063] As shown in Figures 1-8 The present application provides a mountainous highway discarded slag site instability risk zoning evaluation method, which is aimed at the problem of soil and rock mixed discarded slag slope instability risk assessment, proposes a zoning evaluation method and index system, unifies the involved parameters and methods in the relationship of force balance and energy conservation, improves the efficiency of discarded slag engineering instability risk assessment under complex surrounding environment conditions, including the following steps:

[0064] S1: Establish a slope model to simulate the mechanism of the instability of the waste rock slope, and divide the instability process of the waste rock slope of the mountainous highway into stages in combination with the actual instability process of the waste rock slope; specifically, the instability process of the waste rock slope of the mountainous highway is divided into an initial limit equilibrium stage, a slope surface starting and accelerating sliding and sliding to the slope toe stage, and a ground decelerating sliding until stopping stage; in the initial limit equilibrium stage, after the rock-soil mass is fully deformed due to the destruction, a dominant sliding surface is generated, so that the waste rock slope forms a whole sliding, at this time, the sliding starts, the waste rock slope sliding body along the sliding surface is in a limit equilibrium state, the sliding force is equal to the anti-sliding force, and the static friction of the waste rock sliding surface plays a leading role in this stage; in the slope surface starting and accelerating sliding and sliding to the slope toe stage, the sliding body starts to slide along the sliding surface, the sliding force is greater than the anti-sliding force, the sliding body accelerates to slide along the sliding surface, until the potential energy is completely converted into kinetic energy, and the sliding body reaches the maximum speed at the slope toe; in this process, the waste rock sliding friction performance plays a leading role in this accelerating process, and the sliding friction coefficient of the sliding body along the sliding surface continuously decreases with the acceleration of the speed; in the ground decelerating sliding until stopping stage, after the sliding body reaches the slope toe, the sliding body starts to slide along the ground, the anti-sliding force is greater than the sliding force, and with the sliding body moving away from the slope toe and gradually decelerating until the kinetic energy is exhausted at the maximum movement distance position, the waste rock sliding friction performance plays a leading role in this decelerating process, and the sliding friction coefficient of the sliding body along the ground continuously increases with the deceleration.

[0065] S2: Establish the force balance equations of each stage in step S1; specifically, the force balance equations of the initial limit equilibrium stage of the waste rock slope sliding body along the sliding surface, the force balance equations of the accelerating sliding of the waste rock slope sliding body along the sliding surface with the sliding force being greater than the anti-sliding force, and the force balance equations of the decelerating sliding of the waste rock slope sliding body along the ground with the frictional resistance being greater than the sliding force; the force balance equations of the initial limit equilibrium stage of the waste rock slope along the sliding surface are represented by equations (1)-(4):

[0066] T1=F0 (1)

[0067] T1=G sin j1 (2)

[0068] N1=G cos j1 (3)

[0069] F0=CL1+G cos j1μ1(0) (4)

[0070] In the equations, F0 is the static limit frictional resistance of the sliding body gravity G along the normal force N1 of the sliding surface; T1 is the tangential force of the sliding body gravity G along the sliding surface pointing to the slope toe; μ1(0) is the static friction coefficient of the slope surface; G is the gravity; C is the cohesion; L1 is the sliding surface length; j1 is the angle between the sliding surface and the horizontal surface;

[0071] The force balance equations of the accelerating sliding of the waste rock slope sliding body along the sliding surface with the sliding force being greater than the anti-sliding force are represented by equations (5)-(8):

[0072] R1= T1- F1 (5)

[0073] T1= G sin j1 (6)

[0074] N1= G cos j1 (7)

[0075] F1= G cos j1μ1(v1) (8)

[0076] wherein R1is the residual sliding force of the sliding body on the sliding surface; T1is the tangential component of the gravity G of the sliding body along the sliding surface pointing to the slope toe; F1is the sliding friction force of the gravity G of the sliding body along the normal component N1of the sliding surface; μ1is the sliding friction coefficient of the sliding body and the sliding surface; v1is the sliding speed of the sliding body along the sliding surface; μ1is negatively correlated with the sliding speed v1of the sliding body along the sliding surface; j1is the angle between the sliding surface and the horizontal plane; wherein the maximum speed of the sliding body moving to the slope toe is calculated by formula (9):

[0077] v 1max = at (9)

[0078] wherein a is the acceleration of the sliding body under the residual sliding force; t is the time of the sliding body moving to the slope toe; v 1max is the maximum speed of the sliding body moving to the slope toe;

[0079] The residual sliding force R1of the sliding body on the sliding surface can also be calculated by formula (10):

[0080] R1= ma (10)

[0081] wherein a is the acceleration of the sliding body under the residual sliding force; m is the mass of the sliding body, G = mg, g is the acceleration of gravity, generally taken as 9.8 m / s 2 ;

[0082] The acceleration a of the sliding body under the residual sliding force is calculated by formula (11):

[0083] a = g sin j1- g cos j1μ1(v1) (11);

[0084] The relationship between the centroid height h of the sliding body, the acceleration a of the sliding body under the residual sliding force, the time t of the sliding body moving to the slope toe and the angle j1between the sliding surface and the horizontal plane is represented by formula (12):

[0085]

[0086] It can be known from the above formula (9) to formula (12) that the maximum speed v 1max of the sliding body moving to the slope toe can also be represented as:

[0087]

[0088] wherein h is the height of the centroid of the sliding body, which can be obtained by using the massprop command in cad according to the shape of the sliding body; and g is the acceleration of gravity;

[0089] The force balance equation of the deceleration sliding of the waste rock slope sliding body along the ground with the ground friction force being greater than the sliding force is represented by equations (14) to (17):

[0090] R2 = F2 - T2 (14)

[0091] T2 = G sin j2 (15)

[0092] N2 = G cos j2 (16)

[0093] F2 = G cos j2 μ2 (v2) (17)

[0094] wherein R2 is the residual friction force of the sliding body on the ground; F2 is the friction force generated by the normal component of the gravity G of the sliding body along the ground; T2 is the sliding force generated by the tangent component of the gravity G of the sliding body along the ground; N2 is the normal component of the gravity G of the sliding body along the ground; μ2 is the sliding friction coefficient of the sliding body and the ground; v2 is the sliding speed of the sliding body along the ground; and j2 is the inclination angle of the ground;

[0095] S3: On the basis of the force balance equation established in step S2, the movement distance equation of the waste rock sliding body along the ground is obtained by using the kinetic energy friction dissipation balance equation, wherein the kinetic energy friction dissipation balance equation is represented by equation (18):

[0096]

[0097] wherein L2 is the sliding distance of the sliding body on the ground; v 1max is the maximum speed of the sliding body moving to the slope foot;

[0098] The movement distance equation of the waste rock sliding body along the ground is obtained by substituting equations (14) to (17) into equation (18), and is represented by equation (19):

[0099]

[0100] wherein v2 is the sliding speed of the sliding body along the ground; μ2 is the sliding friction coefficient of the sliding body and the ground, which is negatively related to the sliding speed v2 of the sliding body along the ground; L2 is the sliding distance of the sliding body on the ground; and j2 is the inclination angle of the ground;

[0101] S4: When the sliding friction coefficient along the sliding surface does not consider the saturation factor of the coarse-grained soil and the sliding friction coefficient along the ground does not consider the pore water pressure ratio of the coarse-grained soil, the sliding friction coefficient of the sliding body and the sliding surface is consistent with the sliding friction coefficient of the sliding body and the ground, and the maximum value and the minimum value of the friction coefficient are respectively taken to obtain the movement distance equation of the waste rock sliding body along the ground obtained in step S3 to obtain the minimum movement distance and the maximum movement distance of the waste rock sliding body along the ground; according to the evolution law of the static and dynamic friction performance of the waste rock bulk material, the friction performance of the waste rock is negatively related to the speed, that is, the greater the speed, the smaller the sliding friction coefficient, and the smaller the speed, the greater the sliding friction coefficient, and the maximum static friction coefficient (as shown in Figure 8 ). It is generally believed that the slope sliding friction coefficient curve is different from the ground sliding friction coefficient, and for the sake of simplifying the calculation, it can be considered that the two are the same, because the sliding body is the same sliding body, and the sliding body is not considered to be broken and other energy dissipation during sliding, and the friction energy is dominant throughout the process; by using formula (19), assuming that the sliding friction coefficient of the sliding body and the slope and the ground is consistent, when the sliding friction coefficient takes the maximum value, L2 is the minimum movement distance, and the value is L 2min ; when the sliding friction coefficient takes the minimum value, L2 is the maximum movement distance, and the value is L 2max .

[0102] S5: According to the minimum movement distance and the maximum movement distance of the waste rock sliding body along the ground, the waste rock slope instability risk threat is divided into high-risk, medium-risk and low-risk zones, and different colors are used to represent them; specifically, the waste rock slope instability risk threat is divided into: a high-risk zone between the minimum movement distance of the sliding body from the slope toe to the ground and the sliding distance of the sliding body on the ground, which is represented by red, and the sliding distance of the sliding body on the ground is 0~L 2min ; a medium-risk zone between the minimum movement distance and the maximum movement distance of the sliding body on the ground, which is represented by yellow, and the sliding distance of the sliding body on the ground is L 2min ~L 2max ; a low-risk zone outside the maximum movement distance of the sliding body on the ground, which is represented by green, and the sliding distance of the sliding body on the ground is greater than L 2max .

[0103] The application provides a working principle of a mountainous highway spoil site instability risk zoning evaluation method: a mechanical model of spoil sliding along an active sliding surface and a ground surface is used to establish a balance relationship of a sliding force equaling a sliding resistance in an initial limit equilibrium stage of a spoil sliding body, a residual sliding force formula of the spoil sliding body accelerating to slide to a slope toe stage, and a residual sliding resistance formula of the spoil sliding body decelerating to slide to a stop stage on the ground surface, to obtain a maximum speed of the sliding body moving to the slope toe and a residual frictional resistance of the sliding body on the ground surface; a kinetic energy friction dissipation balance equation of kinetic energy equaling friction energy is established by combining a force balance relationship in a deceleration stage, to derive a movement distance equation of the spoil sliding body on the ground surface; under maximum and minimum sliding friction coefficients, minimum and maximum movement distances of the spoil sliding body on the ground surface are obtained respectively; the minimum and maximum movement distances of the spoil sliding body on the ground surface are used to divide spoil instability safety threats into: a red zone between the slope toe and the minimum movement distance, a high risk; a yellow zone between the minimum movement distance and the maximum movement distance, a medium risk; and a green zone outside the maximum movement distance, a low risk; the application can solve the problem that a traditional spoil slope instability risk evaluation method uses different equations to obtain different distances, and there is no uniformity in color marking and zoning standards of different zoning results, and there is a certain randomness, which is not conducive to the authority and comparability of evaluation conclusions.

[0104] Those skilled in the art will easily understand that the above description is only the preferred embodiment of the application and is not intended to limit the application, and any modification, equivalent replacement and improvement within the spirit and principle of the application should be included in the protection scope of the application.

Claims

1. A mountainous highway spoil site instability risk zoning evaluation method, characterized in that: The method comprises the following steps: S1: establishing a slope model to simulate the instability movement mechanism of the waste rock slope, and combining the instability process of the actual waste rock slope to divide the instability process of the waste rock slope of the mountainous highway into stages; S2: establishing a force balance equation for each stage in step S1; S3: on the basis of the force balance equation established in step S2, using a kinetic energy friction dissipation balance equation to obtain a movement distance equation of the waste rock sliding body along the ground; S4: when the sliding friction coefficient of the sliding body along the sliding surface does not consider the saturation factor of the coarse-grained soil and the sliding friction coefficient of the sliding body along the ground does not consider the pore water pressure ratio of the coarse-grained soil, the sliding friction coefficient of the sliding body and the sliding surface and the sliding friction coefficient of the sliding body and the ground are consistent, the maximum value and the minimum value of the sliding friction coefficient are respectively substituted into the movement distance equation of the waste rock sliding body along the ground obtained in step S3 to obtain the minimum movement distance and the maximum movement distance of the waste rock sliding body along the ground; S5: according to the minimum movement distance and the maximum movement distance of the waste rock sliding body along the ground, the waste rock slope instability risk threat is divided into high-risk, medium-risk and low-risk zones, and different colors are used to represent them; The stage division of the instability process of the waste rock slope of the mountainous highway in step S1 comprises an initial limit equilibrium stage, a slope surface starting acceleration sliding and descending to the slope foot stage, and a ground deceleration sliding until stopping stage; The force balance equation in step S2 comprises a force balance equation of the waste rock sliding body along the sliding surface in the initial limit equilibrium stage, a force balance equation of the waste rock sliding body along the sliding surface in the accelerated sliding stage, and a force balance equation of the waste rock sliding body along the ground in the deceleration sliding stage; The force balance equation of the waste rock sliding body along the sliding surface in the initial limit equilibrium stage in step S2 comprises （1） （2） （3） （4） wherein is the gravity of the sliding mass is the normal force along the sliding surface is the static limit friction force under the action of is the gravity of the sliding mass is the tangential force along the sliding surface directed towards the toe is the static friction coefficient of the slope surface is the gravity is the cohesion is the length of the sliding surface is the angle between the sliding surface and the horizontal The force balance equation of the waste rock sliding body along the sliding surface in the accelerated sliding stage in step S2 comprises （5） （6） （7） （8） wherein is the residual sliding force of the sliding mass on the sliding surface; is the gravity of the sliding mass is the normal force of the sliding surface is the sliding friction force under the action of the sliding mass; is the sliding friction coefficient of the sliding mass on the sliding surface; is the sliding velocity of the sliding mass on the sliding surface; is the sliding velocity of the sliding mass on the sliding surface is negatively correlated; The force balance equation of the waste rock sliding body along the ground in the deceleration sliding stage in step S2 comprises （14） （15） （16） （17） wherein is the residual friction of the slide on the ground; is the gravity of the slide is the friction generated along the normal component of the ground; is the gravity of the slide is the sliding force generated along the tangent component of the ground; is the gravity of the slide is the normal component of the ground; is the sliding friction coefficient of the slide on the ground; is the speed of the slide along the ground; is the speed of the slide along the ground is inversely proportional; is the ground inclination.

2. The mountainous highway spoil site instability risk zoning evaluation method according to claim 1, characterized in that In step S5, the high-risk zone is between the minimum movement distance of the sliding body from the slope foot to the ground sliding, represented by red; the medium-risk zone is between the minimum movement distance and the maximum movement distance of the sliding body on the ground sliding, represented by yellow; and the low-risk zone is outside the maximum movement distance of the sliding body on the ground sliding, represented by green.

3. The mountainous highway spoil site instability risk zoning evaluation method according to claim 2, characterized in that: The maximum speed of the sliding body moving to the slope foot is calculated by formula (9): （9） wherein is the acceleration of the sliding mass under the action of the residual sliding force; is the time for the sliding mass to reach the toe of the slope; is the maximum velocity of the sliding mass to reach the toe of the slope; the remaining sliding force of the sliding body on the sliding surface may also be calculated by equation (10): （10） In the formula, is the mass of the slide.

4. The mountainous highway spoil site instability risk zoning evaluation method according to claim 3, characterized in that: Acceleration of the sliding mass under the action of the residual sliding force This is calculated by equation (11) （11） wherein g is the acceleration due to gravity, having a value of 9.8 m / s 2 ; the height of the centroid of the sliding mass the acceleration of the sliding mass under the action of the residual sliding force the time of motion of the sliding mass to the toe of the slope and the angle between the sliding surface and the horizontal The relationship between these quantities is given by equation (12): （12）； Maximum velocity of the sliding mass to the toe of the slope Also expressed as: （13）。 5. The mountainous highway spoil site instability risk zoning evaluation method according to claim 3, characterized in that: The kinetic energy friction dissipation balance equation in step S3 is represented by formula (18): （18） wherein: is the distance of the sliding mass on the ground surface; is the maximum velocity of the sliding mass to the toe of the slope.

6. The mountainous highway spoil site instability risk zoning evaluation method according to claim 5, characterized in that: The movement distance equation of the waste rock sliding body along the ground in step S3 is represented by formula (19): （19） In the formula, is the distance of the sliding mass on the ground.

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