A double-index-based falling type dangerous rock body identification method and device

Abstract

The present application relates to the technical field of falling type dangerous rock body identification and early warning, and particularly discloses a falling type dangerous rock body identification method and device based on double indexes. The cohesion, internal friction angle, density, initial rock bridge length, self weight, thickness, length, tensile strength, natural vibration frequency, friction coefficient on the structural plane, and effective normal stress on the structural plane of the falling type dangerous rock body to be identified are obtained. The damping ratio of the falling type dangerous rock body after damage and the rock bridge length of the falling type dangerous rock body at different time after damage are calculated. The shear safety factor and the tensile-shear safety factor of the falling type dangerous rock body are calculated. The dynamic safety factor and the weak stability dynamic safety factor of the falling type dangerous rock body are calculated. Based on the dynamic safety factor and the weak stability dynamic safety factor, the falling type dangerous rock body to be identified is identified according to a preset identification rule, and an identification result is obtained. The present application can improve the accuracy and efficiency of falling type rock body damage identification.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of identification and early warning of falling dangerous rock mass, in particular to a falling dangerous rock mass identification method and device based on double indexes. BACKGROUND

[0002] In recent years, with the gradual expansion of engineering construction activities to complex and variable mountain and canyon areas, the identification and monitoring of falling dangerous rock mass becomes particularly important. The steep slopes widely existing in the mountain and canyon not only increase the possibility of rock mass collapse disasters, but also directly threaten the safety and sustainability of engineering construction. Therefore, carrying out scientific and rapid identification and monitoring of falling dangerous rock mass is of great importance to ensure the safety of engineering construction and operation, and has important significance in engineering safety strategy and geological disaster warning and prevention.

[0003] The formation of falling dangerous rock mass is mainly due to the damage of the internal structure of the rock. Under the action of external forces such as earthquakes, rainfall or construction activities, the strength index of rock mass structure surface or rock bridge is prone to deterioration, evolving into a high-risk falling dangerous rock mass. At present, through remote sensing means such as laser scanning technology, radar technology, unmanned aerial vehicle aerial photography technology and infrared thermal imaging technology, combined with intelligent algorithms, dangerous rock mass can be preliminarily identified in engineering. However, these methods are mainly based on mathematical statistical analysis, and cannot realize quantitative analysis of dangerous rock mass from the mechanical point of view, so reasonable mechanical evaluation is still needed during field investigation, resulting in reduced efficiency and accuracy of falling dangerous rock mass damage identification. SUMMARY

[0004] In order to solve the technical problem of reducing the efficiency and accuracy of falling dangerous rock mass damage identification existing in the prior art, the embodiments of the present application provide a falling dangerous rock mass identification method and device based on double indexes. The technical solution is as follows:

[0005] On the one hand, a falling dangerous rock mass identification method based on double indexes is provided, which is realized by a falling dangerous rock mass identification device, and the method comprises:

[0006] S1, obtaining the cohesion, internal friction angle, density, initial rock bridge length, self-weight, thickness, length, tensile strength, natural vibration frequency, friction coefficient on the structure surface and effective normal stress on the structure surface of the falling dangerous rock mass to be identified;

[0007] S2, calculating the damping ratio of the damaged falling dangerous rock mass according to the friction coefficient on the structure surface and the effective normal stress;

[0008] S3, calculating the rock bridge length of the falling dangerous rock mass at different times after damage according to the obtained natural vibration frequency, initial rock bridge length and calculated damping ratio;

[0009] S4, calculate the shear safety factor of the falling dangerous rock mass according to the cohesion, the effective normal stress on the structural plane, the internal friction angle, the density, the length, the thickness and the rock bridge length;

[0010] S5, calculate the tensile-shear safety factor of the falling dangerous rock mass according to the tensile strength, the cohesion, the effective normal stress on the structural plane, the internal friction angle, the density, the length, the thickness and the rock bridge length;

[0011] S6, calculate the dynamic safety factor and the weak stable dynamic safety factor of the falling dangerous rock mass according to the shear safety factor and the tensile-shear safety factor of the falling dangerous rock mass;

[0012] S7, based on the dynamic safety factor and the weak stable dynamic safety factor, perform falling dangerous rock mass identification on the falling dangerous rock mass to be identified according to a preset identification rule, and obtain an identification result.

[0013] In another aspect, a falling dangerous rock mass identification device based on double indexes is provided, which is applied to a falling dangerous rock mass identification method based on double indexes, and the device comprises:

[0014] An acquisition module is configured to acquire the cohesion, the internal friction angle, the density, the initial rock bridge length, the self-weight, the thickness, the length, the tensile strength, the natural vibration frequency, the friction coefficient on the structural plane and the effective normal stress on the structural plane of the falling dangerous rock mass to be identified;

[0015] A first determination module is configured to calculate the damping ratio of the damaged falling dangerous rock mass according to the friction coefficient on the structural plane and the effective normal stress;

[0016] A second determination module is configured to calculate the rock bridge length of the falling dangerous rock mass at different times after damage according to the acquired natural vibration frequency, the initial rock bridge length and the calculated damping ratio;

[0017] A third determination module is configured to calculate the shear safety factor of the falling dangerous rock mass according to the cohesion, the effective normal stress on the structural plane, the internal friction angle, the density, the length, the thickness and the rock bridge length;

[0018] A fourth determination module is configured to calculate the tensile-shear safety factor of the falling dangerous rock mass according to the tensile strength, the cohesion, the effective normal stress on the structural plane, the internal friction angle, the density, the length, the thickness and the rock bridge length;

[0019] A fifth determination module is configured to calculate the dynamic safety factor and the weak stable dynamic safety factor of the falling dangerous rock mass according to the shear safety factor and the tensile-shear safety factor of the falling dangerous rock mass;

[0020] The identification module is configured to perform the falling-type dangerous rock mass identification on the falling-type dangerous rock mass to be identified according to a preset identification rule based on the dynamic safety factor and the weak-stable dynamic safety factor, and obtain an identification result.

[0021] In another aspect, a falling-type dangerous rock mass identification device is provided, which comprises a processor and a memory having computer readable instructions stored thereon, the computer readable instructions being executed by the processor to implement any one of the above-mentioned falling-type dangerous rock mass identification methods based on double indexes.

[0022] In another aspect, a computer readable storage medium is provided, which stores at least one instruction, the at least one instruction being loaded and executed by a processor to implement any one of the above-mentioned falling-type dangerous rock mass identification methods based on double indexes.

[0023] The technical scheme provided by the embodiments of the present application has at least the following beneficial effects:

[0024] The cohesion, internal friction angle, density, initial rock bridge length, self-weight, thickness, length, tensile strength, natural vibration frequency, friction coefficient on the structural plane and effective normal stress on the structural plane of the falling-type dangerous rock mass to be identified are obtained; the damping ratio of the damaged falling-type dangerous rock mass is calculated according to the friction coefficient on the structural plane and the effective normal stress on the structural plane; the rock bridge length of the falling-type dangerous rock mass at different times after damage is calculated according to the obtained natural vibration frequency, initial rock bridge length and calculated damping ratio; the shear safety factor of the falling-type dangerous rock mass is calculated according to the cohesion, effective normal stress on the structural plane, internal friction angle, density, length, thickness and rock bridge length; the tensile-shear safety factor of the falling-type dangerous rock mass is calculated according to the tensile strength, cohesion, effective normal stress on the structural plane, internal friction angle, density, length, thickness and rock bridge length; the dynamic safety factor and the weak-stable dynamic safety factor of the falling-type dangerous rock mass are calculated according to the shear safety factor and the tensile-shear safety factor of the falling-type dangerous rock mass; the falling-type dangerous rock mass identification is performed on the falling-type dangerous rock mass to be identified according to a preset identification rule based on the dynamic safety factor and the weak-stable dynamic safety factor, and an identification result is obtained. By introducing the dynamic indexes such as the natural vibration frequency, the falling-type dangerous rock mass identification model is established, the rapid damage identification of the falling-type dangerous rock mass is realized, and the accuracy and scientificity of the traditional method are improved. New technical support is provided for early monitoring and early warning of large falling-type dangerous rock mass collapse disasters. BRIEF DESCRIPTION OF DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings needed in the embodiments description. Obviously, the drawings in the following description only constitute some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained from these drawings without creative labor.

[0026] Figure 1 is a flow chart of a falling type dangerous rock body identification method based on double indexes provided by the embodiments of the present application;

[0027] Figure 2 is a falling type dangerous rock freeze-thaw simulation test field photo provided by the embodiments of the present application, wherein (a) is a field photo before damage occurs, and (b) is a field photo after damage occurs;

[0028] Figure 3 is a falling type dangerous rock freeze-thaw test dynamics parameter trend chart provided by the embodiments of the present application;

[0029] Figure 4 is a falling type dangerous rock freeze-thaw simulation test safety factor calculation result trend chart provided by the embodiments of the present application;

[0030] Figure 5 is a falling type dangerous rock freeze-thaw simulation test dynamics safety factor and weak stability dynamics safety factor comparison chart provided by the embodiments of the present application;

[0031] Figure 6 is a falling type dangerous rock position chart provided by the embodiments of the present application;

[0032] Figure 7 is a falling type dangerous rock body identification device block diagram provided by the embodiments of the present application;

[0033] Figure 8 is a structure schematic diagram of a falling type dangerous rock body identification device provided by the embodiments of the present application. DETAILED DESCRIPTION

[0034] The technical solutions in the present application will be described below with reference to the drawings.

[0035] In the embodiments of the present application, the words such as "example", "for example" are used to represent as an example, illustration or description. Any embodiment or design scheme described as "example" in the present application should not be interpreted as more preferred or more advantageous than other embodiments or design schemes. In fact, the word "example" is intended to present the concept in a specific way. In addition, in the embodiments of the present application, the meaning expressed by "and / or" can be both, or can be one of the two.

[0036] In the embodiments of the present application, "image" and "picture" can be used interchangeably, and it should be pointed out that the meanings expressed are consistent when the distinction is not emphasized.

[0037] In the embodiments of the present application, sometimes the subscript such as W1 can be written in the form of non-subscript such as W1, and the meanings expressed are consistent when the distinction is not emphasized.

[0038] To make the technical problems, technical solutions and advantages to be solved by the present application clearer, specific embodiments will be described in detail below with reference to the drawings.

[0039] The embodiments of the present application provide a double-index-based falling-type dangerous rock body identification method, which can be implemented by a falling-type dangerous rock body identification device, which can be a terminal or a server. Figure 1 As shown in the double-index-based falling-type dangerous rock body identification method flowchart, the processing flow of the method can include the following steps:

[0040] S1, obtaining the cohesion, internal friction angle, density, initial rock bridge length, self-weight, thickness, length, tensile strength, natural vibration frequency, friction coefficient on the structural plane and effective normal stress on the structural plane of the falling-type dangerous rock body to be identified.

[0041] The cohesion refers to the bonding strength between the particles inside the rock; the internal friction angle refers to the resistance angle of sliding between the rock particles; the density refers to the mass per unit volume of the rock mass; the initial rock bridge length refers to the length of the unbroken part in the rock crack; the self-weight refers to the gravity of the rock mass itself; the thickness and length refer to the geometric dimensions of the rock mass; the tensile strength refers to the ability of the rock mass to resist tensile failure; and the friction coefficient and effective normal stress on the structural plane refer to the friction characteristics of the rock structural plane under the action of the normal force.

[0042] In a feasible implementation manner, the cohesion, internal friction angle, density, initial rock bridge length, self-weight, thickness, length, tensile strength, friction coefficient on the structural plane and effective normal stress on the structural plane of the falling-type dangerous rock body can be the rock mass data corresponding to the rock mass to be identified obtained through in-situ test, and the natural vibration frequency of the falling-type dangerous rock body structure is measured by using a non-contact remote sensing monitoring technology such as a laser Doppler vibration meter.

[0043] S2, calculating the damping ratio of the damaged falling-type dangerous rock body according to the friction coefficient and effective normal stress on the structural plane.

[0044] Optionally, S2 calculates the damping ratio of the damaged falling-type dangerous rock mass according to the friction coefficient on the structural surface and the effective normal stress, comprising:

[0045] According to the friction coefficient on the structural surface, the effective normal stress and the following formula (1), the damping ratio of the damaged falling-type dangerous rock mass is calculated:

[0046] (1)

[0047] wherein, is the damping ratio of the falling-type dangerous rock mass, is the friction coefficient on the structural surface, N is the effective normal stress on the structural surface, s is the total displacement of the falling-type dangerous rock mass structure single period, and E is the total energy of the falling-type dangerous rock mass structure system, is the damping loss factor.

[0048] Wherein, the total displacement of the falling-type dangerous rock mass structure single period is obtained by using a non-contact measuring device, and the total energy of the falling-type dangerous rock mass structure system is pre-set data.

[0049] S3, according to the obtained natural vibration frequency, the initial rock bridge length and the calculated damping ratio, the rock bridge length of the falling-type dangerous rock mass at different times after damage is calculated.

[0050] Optionally, S3 calculates the rock bridge length of the falling-type dangerous rock mass at different times after damage according to the obtained natural vibration frequency, the initial rock bridge length and the calculated damping ratio, comprising:

[0051] According to the obtained natural vibration frequency, the calculated damping ratio and the following formula (2), the rock bridge length of the falling-type dangerous rock mass at different times after damage is calculated:

[0052] (2)

[0053] wherein, l i is the rock bridge length of the falling-type dangerous rock mass at i time, l0 is the initial rock bridge length of the falling-type dangerous rock mass, f i is the natural vibration frequency of the falling-type dangerous rock mass at i time, f0 is the natural vibration frequency of the falling-type dangerous rock mass at the initial time, is the damping ratio of the falling-type dangerous rock mass at i time, is the damping ratio of the falling-type dangerous rock mass at the initial time.

[0054] S4, according to the cohesion, the effective normal stress on the structural surface, the internal friction angle, the density, the length, the thickness and the rock bridge length, the shear safety factor of the falling-type dangerous rock mass is calculated.

[0055] The shear safety factor (SSF) is a concept in engineering geology and geotechnical engineering used to assess the stability of rock or soil mass or structure under shear action.

[0056] Optionally, the shear safety factor of the falling-type dangerous rock mass is calculated according to the cohesion, the effective normal stress on the structural plane, the internal friction angle, the density, the length, the thickness, and the rock bridge length of the falling-type dangerous rock mass in S4, and the shear safety factor of the falling-type dangerous rock mass is calculated according to the cohesion, the effective normal stress on the structural plane, the internal friction angle, the density, the length, the thickness, and the rock bridge length of the falling-type dangerous rock mass in S4, including:

[0057] The shear safety factor of the falling-type dangerous rock mass is calculated according to the cohesion, the effective normal stress on the structural plane, the internal friction angle, the density, the length, the thickness, and the rock bridge length of the falling-type dangerous rock mass, and the following formula (3):

[0058] (3)

[0059] wherein F si is the shear safety factor of the falling-type dangerous rock mass at the i th moment, c is the cohesion of the falling-type dangerous rock mass, is the effective normal stress on the structural plane of the falling-type dangerous rock mass, is the internal friction angle of the falling-type dangerous rock mass, is the density of the falling-type dangerous rock mass, g is the acceleration of gravity, H is the length of the falling-type dangerous rock mass, L is the thickness of the falling-type dangerous rock mass, and l i is the rock bridge length of the falling-type dangerous rock mass calculated at the i th moment.

[0060] S5, the tensile-shear safety factor of the falling-type dangerous rock mass is calculated according to the tensile strength, the cohesion, the effective normal stress on the structural plane, the internal friction angle, the density, the length, the thickness, and the rock bridge length.

[0061] The tensile-shear safety factor (TSSF) is a parameter used in geotechnical and structural engineering to assess the stability of materials or structures under tensile and shear action. It takes into account the resistance of the material to combined forces, i.e., both tensile and shear forces.

[0062] Optionally, the tensile-shear safety factor of the falling-type dangerous rock mass is calculated according to the tensile strength, the cohesion, the effective normal stress on the structural plane, the internal friction angle, the density, the length, the thickness, and the rock bridge length in S5, and the tensile-shear safety factor of the falling-type dangerous rock mass is calculated according to the tensile strength, the cohesion, the effective normal stress on the structural plane, the internal friction angle, the density, the length, the thickness, and the rock bridge length in S5, including:

[0063] The tensile-shear safety factor of the falling-type dangerous rock mass is calculated according to the tensile strength, the cohesion, the effective normal stress on the structural plane, the internal friction angle, the density, the length, the thickness, and the rock bridge length, and the following formula (4):

[0064] (4)

[0065] wherein, F ti is the tensile-shear safety factor of the falling-type dangerous rock mass at the i moment, R t is the tensile strength at the crack of the falling-type dangerous rock mass, c is the cohesion of the falling-type dangerous rock mass, is the effective normal stress on the structural plane of the falling-type dangerous rock mass, is the internal friction angle of the falling-type dangerous rock mass, is the density of the falling-type dangerous rock mass, g is the acceleration of gravity, H is the length of the falling-type dangerous rock mass, L is the thickness of the falling-type dangerous rock mass, l i is the calculated rock bridge length of the falling-type dangerous rock mass at the i moment.

[0066] S6, calculating the dynamic safety factor and the weak-stable dynamic safety factor of the falling-type dangerous rock mass according to the shear safety factor and the tensile-shear safety factor of the falling-type dangerous rock mass.

[0067] Optionally, the S6 of calculating the dynamic safety factor and the weak-stable dynamic safety factor of the falling-type dangerous rock mass according to the shear safety factor and the tensile-shear safety factor of the falling-type dangerous rock mass, comprises:

[0068] S61, calculating the dynamic safety factor of the falling-type dangerous rock mass according to the shear safety factor, the tensile-shear safety factor of the falling-type dangerous rock mass and the following formula (5):

[0069] (5)

[0070] wherein, DSF is the dynamic safety factor of the falling-type dangerous rock mass, F si is the shear safety factor of the falling-type dangerous rock mass at the i moment, F ti is the tensile-shear safety factor of the falling-type dangerous rock mass at the i moment.

[0071] S62, calculating the weak-stable dynamic safety factor of the falling-type dangerous rock mass according to the shear safety factor, the tensile-shear safety factor of the falling-type dangerous rock mass and the following formula (6):

[0072] (6)

[0073] wherein, WDSF is the weak-stable dynamic safety factor of the falling-type dangerous rock mass, F si is the shear safety factor of the falling-type dangerous rock mass at the i moment, F ti is the tensile-shear safety factor of the falling-type dangerous rock mass at the i moment.

[0074] S7, performing falling-type dangerous rock mass identification on the falling-type dangerous rock mass to be identified according to a preset identification rule based on the dynamic safety factor and the weak-stable dynamic safety factor, to obtain an identification result.

[0075] Optionally, the falling type dangerous rock body identification is performed on the to-be-identified falling type dangerous rock body according to the preset identification rule based on the kinetic safety factor and the weak stable kinetic safety factor in S7, and an identification result is obtained, including:

[0076] The calculated kinetic safety factor DSF and weak stable kinetic safety factor WDSF are analyzed. When both DSF and WDSF are greater than or equal to 1, it is determined that the falling type dangerous rock body is in a strong stable stage, and the falling type dangerous rock body is a stable rock body. When DSF is greater than or equal to 1 and WDSF is less than 1, it is determined that the falling type dangerous rock body is in a weak stable stage, and the falling type dangerous rock body is a dangerous rock body. When both DSF and WDSF are less than 1, it is determined that the falling type dangerous rock body enters an accelerated destruction stage, and the falling type dangerous rock body collapses and is destroyed. In addition, it needs to be noted that due to the limitation of the calculation formula, the situation that DSF is less than 1 and WDSF is greater than or equal to 1 will not occur.

[0077] According to the above theoretical formula, the rapid identification and early warning of the falling type dangerous rock body can be realized.

[0078] The effectiveness and practicality of the method of the embodiment will be described below in combination with an actual case.

[0079] Case 1: In order to illustrate the rationality and feasibility of the method of the case, an indoor test is performed to verify the method. The falling type dangerous rock test model is constructed by adopting the freeze-thaw measure. In order to facilitate freezing and ensure that the dangerous rock and the parent rock material are consistent, two plastic steel blocks are bonded by a low-temperature adhesive, wherein the size of the dangerous rock plastic steel block is 12×3×3 cm, and the plastic steel block of the base rock is bonded to the vertical surface of a large-size marble block by a strong adhesive to ensure that the plastic steel block of the base rock and the marble block are regarded as a whole when vibrating. The size of the plastic steel block of the base rock is 12×10×3 cm, and the size of the marble block is 50×50×50 cm. The test block is frozen for 72 hours under the condition of-7℃ low temperature, and then the test block is bonded to the vertical surface of the marble block after being taken out by instant strong adhesive. There is no external interference during the test, and the bonding degree of the low-temperature adhesive slowly decreases over time under the condition of room temperature, which can simulate the whole process of natural degradation of the rock bridge. The vibration signal of the dangerous rock in the whole process from stability to collapse is collected by a vibration pickup. After several tests, it is found that the whole process time of the dangerous rock from stability to destruction is about 1950s, and one of the test groups is selected for result analysis. The dangerous rock block collapses at the 1954s in this test, and the test photo is shown in FIG. 1. Figure 2

[0080] The micro-vibration data collected in the test are analyzed and processed, the inherent vibration frequency of the dangerous rock is extracted by fast Fourier transform, and the corresponding damping ratio is calculated by the half-power bandwidth method. The data results obtained after filtering and denoising the vibration signal are shown in Table 1, and the trend change is shown in FIG. 2.​Figure 3 The natural frequency and damping ratio gradually decrease with the weakening of the low-temperature adhesive, the natural frequency decreases from 181.1 Hz to 31.66 Hz, and the damping ratio decreases from 0.59% to 0.27%, which verifies the correspondence between the strength change of the low-temperature adhesive used in the test and the dynamic parameters from the monitoring data.

[0081] Table 1

[0082] Time / s Natural frequency / Hz Damping ratio F t ]]> F s ]]> DSF WDSF 2 181.10 0.59 51.74 10.00 10.00 5.17 67 182.57 0.58 52.61 10.08 10.08 5.21 125 181.22 0.55 51.81 10.00 10.00 5.17 187 176.04 0.54 48.81 9.72 9.72 5.02 258 173.08 0.47 47.14 9.55 9.55 4.93 322 171.47 0.43 46.24 9.46 9.46 4.88 384 170.59 0.43 45.75 9.41 9.41 4.85 421 168.41 0.41 44.56 9.29 9.29 4.75 480 172.00 0.41 46.53 9.49 9.49 4.90 560 170.49 0.39 45.70 9.41 9.41 4.85 621 168.28 0.38 44.48 9.29 9.29 4.78 681 166.45 0.38 43.49 9.19 9.19 4.73 738 164.94 0.37 42.68 9.10 9.10 4.68 806 160.06 0.34 40.12 8.83 8.83 4.53 856 156.87 0.34 38.49 8.66 8.66 4.44 912 154.83 0.35 37.46 8.54 8.54 4.38 971 153.28 0.34 36.69 8.46 8.46 4.33 1027 146.47 0.34 33.40 8.08 8.08 4.12 1089 122.91 0.34 23.19 6.78 6.78 3.41 1152 119.47 0.34 21.86 6.59 6.59 3.31 1227 115.96 0.34 20.54 6.40 6.40 3.20 1301 110.42 0.35 18.54 6.09 6.09 3.04 1357 110.04 0.35 18.40 6.07 6.07 3.02 1417 94.87 0.35 13.46 5.23 5.23 2.57 1475 91.37 0.33 12.43 5.04 5.04 2.46 1541 90.40 0.31 12.15 4.99 4.99 2.43 1594 80.35 0.31 9.45 4.43 4.43 2.12 1647 71.95 0.30 7.44 3.97 3.97 1.87 1704 48.33 0.29 3.07 2.66 2.66 1.15 1761 40.53 0.29 2.03 2.23 2.03 0.90 1814 36.49 0.29 1.57 2.01 1.57 0.78 1873 33.91 0.29 1.30 1.87 1.33 0.69 1916 34.60 0.28 1.37 1.91 1.37 0.71 1954 31.66 0.27 1.09 1.74 1.09 0.62

[0083] Shear safety factor F s and tensile-shear combined safety factor F t The calculation results of F and F are listed in Table 1, and the trend comparison diagram is shown in Figure 4 As can be seen from the above test results, the tensile-shear combined safety factor F t is much larger than the shear safety factor F s in the early stage of the test, which is consistent with the analysis acceleration in rock bridge degradation and the test results. From the data results at the end of the freeze-thaw test, it can be seen that the shear safety factor F s starts to be greater than the tensile-shear combined safety factor F t at about 1761 s, indicating that the dangerous rock mass starts to change the main control stress state, and finally F s The calculation result of F is 1.74, and the calculation result of F is 1.09, which fully illustrates that the final failure of the dangerous rock is the falling damage under the tensile-shear combined action. It is worth noting that in this test, the main control stress of the dangerous rock mass changes in the late stage of the test, which is different from the results of the rock bridge degradation test. The reason for this phenomenon can be attributed to the fact that in the freeze-thaw test, the weakening form of the main control structure surface strength is relatively uniform and slow, which is different from the local burst weakening in the rock bridge degradation test. During the early and middle stages of the adhesive weakening process, no through cracks appear, so the stress condition of tensile-shear combination cannot be met. In the late stage of the test, a continuous crack is formed due to the liquefaction of the adhesive, at which time the dangerous rock mass enters the main control stress state of tensile-shear combination, at which time the rock mass is subjected to a rapid increase in tensile-shear combined stress, and the safety factor shows a clear downward trend, and when F t is close to 1, the dangerous rock mass collapses.

[0084] The DSF and WDSF results calculated according to formula (5) and formula (6) are listed in Table 1, and the trend comparison is shown in Figure 5The test block is in a stable state before 1761 s, and the transition of the main stress state occurs after 1761 s, at which time the test block enters a weakly stable stage, and the test model can be regarded as a "dangerous rock mass". By comparing the calculation results of DSF, it can be seen that, compared with the failure time node, WDSF enters the weakly stable stage 239 s in advance; in addition, DSF decreases significantly in the period before entering the weakly stable stage, indicating that at this time node, the rock bridge strength of the dangerous rock mass has deteriorated sharply, and the main controlling structural plane of the rock mass has begun to crack and strength to decay, entering the weakly stable stage.

[0085] In summary, the test analysis results fully demonstrate that the case implementation method shows good accuracy and dynamic identification characteristics in dealing with the dynamic safety evaluation of falling dangerous rock. The DSF calculation result of the test model before falling failure is 1.09. In terms of dangerous rock identification, the weakly stable safety factor based on the kinetic parameters can also effectively identify the stress state transition node of the falling dangerous rock, and realize the identification of the weakly stable stage of the rock block.

[0086] Case two: In order to verify the applicability and accuracy of the case implementation method, an actual case is selected for application practice. The application case selects a typical falling dangerous rock at the cliff of Baquan Pumped Storage Power Station in the southeast of Taihang Mountain as the research object. The joint at the top of the cliff rock mass is nearly vertical, and the rear edge crack has no filling material. The research object is a typical falling dangerous rock block, and the specific location and field conditions are shown in Figure 6 According to the geological survey report, the target dangerous rock mass is quartz sandstone, and the relevant physical parameters and mechanical parameters in the geological survey are shown in Table 2. In the field monitoring work, due to the dangerous location of the dangerous rock, a laser Doppler vibration meter is used to measure the remote kinetic parameters of the dangerous rock. The target is measured from three directions, and its DSF and WDSF are calculated. The calculation results are shown in Table 3. The results show that the DSF and WDSF of the falling dangerous rock are both greater than 1, and are in a stable stage, which is consistent with the exploration results.

[0087] Table 2

[0088] Density / kg m -3 ]] 2653 Elastic modulus / GPa 20 Poisson's ratio 0.28 Cohesion / MPa 1.1 Tensile strength / MPa 1.1

[0089] Table 3

[0090] Monitoring point Natural frequency / Hz Damping ratio / % DSF WDSF 1 121.2 1.2 2.64 1.38 2 122.0 1.7 2.59 1.29 3 121.8 1.3 2.71 1.33 Average 121.7 14 2.65 1.33

[0091] In the embodiment of the present application, the cohesion, internal friction angle, density, initial rock bridge length, self weight, thickness, length, tensile strength, natural vibration frequency, friction coefficient on the structural plane and effective normal stress on the structural plane of the falling type dangerous rock mass to be identified are obtained; the damping ratio of the damaged falling type dangerous rock mass is calculated according to the friction coefficient on the structural plane and the effective normal stress; the rock bridge length of the falling type dangerous rock mass at different times after damage is calculated according to the obtained natural vibration frequency, initial rock bridge length and calculated damping ratio; the shear safety factor of the falling type dangerous rock mass is calculated according to the cohesion, effective normal stress on the structural plane, internal friction angle, density, length, thickness and rock bridge length; the tension-shear safety factor of the falling type dangerous rock mass is calculated according to the tensile strength, cohesion, effective normal stress on the structural plane, internal friction angle, density, length, thickness and rock bridge length; the dynamic safety factor and weak stability dynamic safety factor of the falling type dangerous rock mass are calculated according to the shear safety factor and tension-shear safety factor of the falling type dangerous rock mass; and the falling type dangerous rock mass identification of the falling type dangerous rock mass to be identified is performed according to the preset identification rule based on the dynamic safety factor and weak stability dynamic safety factor, so as to obtain an identification result. In the embodiment of the present application, the dynamic index such as natural vibration frequency is introduced to establish a falling type dangerous rock mass identification model, so that the rapid damage identification of the falling type dangerous rock mass is realized, and the accuracy and scientificity of the traditional method are improved. A new technical support is provided for early monitoring and early warning of large falling type dangerous rock mass collapse disaster.

[0092] Figure 7 is a kind of falling type dangerous rock mass identification device block diagram based on double index according to an exemplary embodiment, which is used for falling type dangerous rock mass identification method based on double index. Refer to Figure 7 The device includes acquisition module 710, first determination module 720, second determination module 730, third determination module 740, fourth determination module 750, fifth determination module 760 and identification module 770. Wherein:

[0093] The acquisition module 710 is used to obtain the cohesion, internal friction angle, density, initial rock bridge length, self weight, thickness, length, tensile strength, natural vibration frequency, friction coefficient on the structural plane and effective normal stress on the structural plane of the falling type dangerous rock mass to be identified;

[0094] The first determination module 720 is used to calculate the damping ratio of the damaged falling type dangerous rock mass according to the friction coefficient on the structural plane and the effective normal stress;

[0095] The second determination module 730 is used to calculate the rock bridge length of the falling type dangerous rock mass at different times after damage according to the obtained natural vibration frequency, initial rock bridge length and calculated damping ratio;

[0096] The third determining module 740 is configured to calculate the shear safety factor of the falling dangerous rock mass according to the cohesion, the effective normal stress on the structural plane, the internal friction angle, the density, the length, the thickness, and the rock bridge length.

[0097] The fourth determining module 750 is configured to calculate the tensile-shear safety factor of the falling dangerous rock mass according to the tensile strength, the cohesion, the effective normal stress on the structural plane, the internal friction angle, the density, the length, the thickness, and the rock bridge length.

[0098] The fifth determining module 760 is configured to calculate the dynamic safety factor and the weak-stable dynamic safety factor of the falling dangerous rock mass according to the shear safety factor and the tensile-shear safety factor of the falling dangerous rock mass.

[0099] The identification module 770 is configured to perform falling dangerous rock mass identification on the falling dangerous rock mass to be identified according to a preset identification rule based on the dynamic safety factor and the weak-stable dynamic safety factor, and obtain an identification result.

[0100] Optionally, the first determining module 720 is configured to:

[0101] The damping ratio of the damaged falling dangerous rock mass is calculated according to the friction coefficient on the structural plane, the effective normal stress, and the following formula (1):

[0102] (1)

[0103] wherein, is the damping ratio of the falling dangerous rock mass, is the friction coefficient on the structural plane, N is the effective normal stress on the structural plane, s is the total displacement of the falling dangerous rock mass structure in a single period, and E is the total energy of the falling dangerous rock mass structure system. is the damping loss factor.

[0104] Optionally, the second determining module 730 is configured to:

[0105] The rock bridge length of the damaged falling dangerous rock mass at different times is calculated according to the obtained natural vibration frequency, the calculated damping ratio, and the following formula (2):

[0106] (2)

[0107] wherein, l i is the rock bridge length of the falling dangerous rock mass at the i-th moment, l0 is the initial rock bridge length of the falling dangerous rock mass, f i is the natural vibration frequency of the falling dangerous rock mass at the i-th moment, f0 is the natural vibration frequency of the falling dangerous rock mass at the initial moment, is the damping ratio of the falling dangerous rock mass at the i-th moment, The damping ratio of the falling dangerous rock mass at an initial moment.

[0108] Optionally, the third determining module 740 is configured to:

[0109] The shear safety factor of the falling dangerous rock mass is calculated according to the cohesion, the effective normal stress on the structural plane, the internal friction angle, the density, the length, the thickness, the rock bridge length, and the following formula (3):

[0110] (3)

[0111] wherein, F si is the shear safety factor of the falling dangerous rock mass at the i moment, c is the cohesion of the falling dangerous rock mass, is the effective normal stress on the structural plane of the falling dangerous rock mass, is the internal friction angle of the falling dangerous rock mass, is the density of the falling dangerous rock mass, g is the acceleration of gravity, H is the length of the falling dangerous rock mass, L is the thickness of the falling dangerous rock mass, l i is the calculated rock bridge length of the falling dangerous rock mass at the i moment.

[0112] Optionally, the fourth determining module 750 is configured to:

[0113] The tensile-shear safety factor of the falling dangerous rock mass is calculated according to the tensile strength, the cohesion, the effective normal stress on the structural plane, the internal friction angle, the density, the length, the thickness, the rock bridge length, and the following formula (4):

[0114] (4)

[0115] wherein, F ti is the tensile-shear safety factor of the falling dangerous rock mass at the i moment, R t is the tensile strength at the crack of the falling dangerous rock mass, c is the cohesion of the falling dangerous rock mass, is the effective normal stress on the structural plane of the falling dangerous rock mass, is the internal friction angle of the falling dangerous rock mass, is the density of the falling dangerous rock mass, g is the acceleration of gravity, H is the length of the falling dangerous rock mass, L is the thickness of the falling dangerous rock mass, l i is the calculated rock bridge length of the falling dangerous rock mass at the i moment.

[0116] Optionally, the fifth determining module 760 is configured to:

[0117] S61, the dynamic safety factor of the falling dangerous rock mass is calculated according to the shear safety factor, the tensile-shear safety factor of the falling dangerous rock mass, and the following formula (5):

[0118] (5)

[0119] wherein, DSF is a dynamic safety factor of the falling dangerous rock mass, F si is a shear safety factor of the falling dangerous rock mass at i moment, F ti is a tensile-shear safety factor of the falling dangerous rock mass at i moment.

[0120] S62, according to the shear safety factor, the tensile-shear safety factor of the falling dangerous rock mass and the following formula (6), calculating the weak stability dynamic safety factor of the falling dangerous rock mass:

[0121] (6)

[0122] wherein, WDSF is a weak stability dynamic safety factor of the falling dangerous rock mass, F si is a shear safety factor of the falling dangerous rock mass at i moment, F ti is a tensile-shear safety factor of the falling dangerous rock mass at i moment.

[0123] Optionally, the judging module 770 is used for:

[0124] analyzing the calculated dynamic safety factor DSF and the weak stability dynamic safety factor WDSF, when DSF and WDSF are both greater than or equal to 1, it is determined that the falling dangerous rock mass is in a strong stability stage, at this time, the falling dangerous rock mass is a stable rock mass; when DSF is greater than or equal to 1 and WDSF is less than 1, it is determined that the falling dangerous rock mass is in a weak stability stage, the falling dangerous rock mass is a dangerous rock mass; when DSF and WDSF are both less than 1, it is determined that the falling dangerous rock mass enters an accelerated destruction stage, and the falling dangerous rock mass collapses and destroys.

[0125] In the embodiment of the present application, the cohesion, internal friction angle, density, initial rock bridge length, self-weight, thickness, length, tensile strength, natural vibration frequency, friction coefficient on the structural plane and effective normal stress on the structural plane of the falling type dangerous rock mass to be identified are obtained; the damping ratio of the damaged falling type dangerous rock mass is calculated according to the friction coefficient on the structural plane and the effective normal stress; the rock bridge length of the falling type dangerous rock mass at different times after damage is calculated according to the obtained natural vibration frequency, initial rock bridge length and calculated damping ratio; the shear safety factor of the falling type dangerous rock mass is calculated according to the cohesion, effective normal stress on the structural plane, internal friction angle, density, length, thickness and rock bridge length; the tension-shear safety factor of the falling type dangerous rock mass is calculated according to the tensile strength, cohesion, effective normal stress on the structural plane, internal friction angle, density, length, thickness and rock bridge length; the dynamic safety factor and weak stability dynamic safety factor of the falling type dangerous rock mass are calculated according to the shear safety factor and tension-shear safety factor of the falling type dangerous rock mass; and the falling type dangerous rock mass identification of the falling type dangerous rock mass to be identified is performed according to the preset identification rule based on the dynamic safety factor and weak stability dynamic safety factor, so as to obtain an identification result. In the embodiment of the present application, the falling type dangerous rock mass identification model is established by introducing the dynamic index such as the natural vibration frequency, so that the rapid damage identification of the falling type dangerous rock mass is realized, and the accuracy and scientificity of the traditional method are improved. A new technical support is provided for realizing early monitoring and early warning of large falling type dangerous rock mass collapse disaster.

[0126] Figure 8 is a structural schematic diagram of a falling type dangerous rock mass identification device provided by the embodiment of the present application, as shown in Figure 8 , the falling type dangerous rock mass identification device can include the double-index-based falling type dangerous rock mass identification device shown in Figure 7 . Optionally, the falling type dangerous rock mass identification device 810 can include the first processor 2001.

[0127] Optionally, the falling type dangerous rock mass identification device 810 can further include the memory 2002 and the transceiver 2003.

[0128] Among them, the first processor 2001 and the memory 2002 and the transceiver 2003 can be connected through a communication bus.

[0129] The specific components of the falling type dangerous rock mass identification device 810 will be introduced below: Figure 8

[0130] ​The first processor 2001 is the control center of the falling rock mass identification device 810. It can be a single processor or a collective term for multiple processing elements. For example, the first processor 2001 can be one or more central processing units (CPUs), application-specific integrated circuits (ASICs), or one or more integrated circuits configured to implement embodiments of the present invention, such as one or more digital signal processors (DSPs), or one or more field-programmable gate arrays (FPGAs).

[0131] Optionally, the first processor 2001 can perform various functions of the falling rock mass identification device 810 by running or executing software programs stored in the memory 2002 and calling data stored in the memory 2002.

[0132] In a specific implementation, as one example, the first processor 2001 may include one or more CPUs, for example... Figure 8 CPU0 and CPU1 are shown in the diagram.

[0133] In a specific implementation, as one example, the falling rock mass identification device 810 may also include multiple processors, such as... Figure 8 The first processor 2001 and the second processor 2004 are shown in the diagram. Each of these processors can be a single-core processor or a multi-core processor. Here, a processor can refer to one or more devices, circuits, and / or processing cores used to process data (such as computer program instructions).

[0134] The memory 2002 is used to store the software program that executes the present invention, and is controlled by the first processor 2001 to execute it. The specific implementation method can be referred to the above method embodiment, and will not be repeated here.

[0135] Optionally, the memory 2002 can be a read-only memory (ROM) or other type of static storage device that can store static information and instructions, a random access memory (RAM) or other type of dynamic storage device that can store information and instructions, an electrically erasable programmable read-only memory (EEPROM), a compact disc read-only memory (CD-ROM) or other optical disk storage, a magnetic disk storage or other magnetic storage devices, or any other medium capable of storing desired program code in the form of instructions or data structures and that can be accessed by a computer, but is not limited to this. The memory 2002 can be integrated with the first processor 2001 or exist independently and be coupled with the first processor 2001 through an interface circuit (not shown in the figure) of the falling dangerous rock body identification device 810, and the embodiments of the present application do not make specific limitations here. Figure 8

[0136] The transceiver 2003 is configured to communicate with a network device or a terminal device.

[0137] Optionally, the transceiver 2003 can include a receiver and a transmitter (not shown separately in the figure). The receiver is configured to realize a receiving function, and the transmitter is configured to realize a transmitting function. Figure 8

[0138] Optionally, the transceiver 2003 can be integrated with the first processor 2001 or exist independently and be coupled with the first processor 2001 through an interface circuit (not shown in the figure) of the falling dangerous rock body identification device 810, and the embodiments of the present application do not make specific limitations here. Figure 8

[0139] It should be noted that the structure of the falling dangerous rock body identification device 810 shown in the figure does not constitute a limitation on the router, and the actual knowledge structure identification device can include more or fewer components than those shown in the figure, or combine certain components, or different component arrangements. Figure 8 In addition, the technical effects of the falling dangerous rock body identification device 810 can refer to the technical effects of the falling dangerous rock body identification method based on double indexes described in the above method embodiments, which will not be described here.

[0140]

[0141] ​​​​It is to be understood that the first processor 2001 in the embodiments of the present application can be a central processing unit (CPU), and can also be other general-purpose processors, digital signal processors (DSP), application specific integrated circuits (ASIC), field programmable gate arrays (FPGA) or other programmable logic devices, discrete gates or transistor logic components, discrete hardware components, etc. The general-purpose processor can be a microprocessor or can also be any conventional processor.

[0142] It is also to be understood that the memory in the embodiments of the present application can be a volatile memory or a non-volatile memory, or can include both volatile and non-volatile memory. Among them, the non-volatile memory can be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically EPROM (EEPROM) or a flash memory. The volatile memory can be a random access memory (RAM) used as an external cache. By way of example but not limitation, many forms of random access memory (RAM) are available, such as static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDR SDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchlink dynamic random access memory (SLDRAM) and direct rambus RAM (DR RAM).

[0143] The above-described embodiments can be implemented in whole or in part by software, hardware (such as a circuit), firmware, or any combination thereof. When implemented in software, the above-described embodiments can be implemented in the form of a computer program product. The computer program product includes one or more computer instructions or computer programs. When the computer instructions or computer programs are loaded or executed on a computer, the processes or functions described in the embodiments of the present application are wholly or partially generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions can be stored in a computer-readable storage medium or transferred from one computer-readable storage medium to another computer-readable storage medium, for example, the computer instructions can be transferred from one website, computer, server, or data center to another website, computer, server, or data center through a wired (such as infrared, wireless, microwave, etc.) manner. The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server, data center, etc. containing one or more available medium collections. The available medium can be a magnetic medium (such as a floppy disk, a hard disk, a magnetic tape), an optical medium (such as a DVD), or a semiconductor medium. The semiconductor medium can be a solid-state disk.

[0144] It should be understood that the term "and / or" herein merely describes the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B can represent the following three cases: A exists alone, A and B exist together, and B exists alone, where A and B can be singular or plural. In addition, the character " / " herein generally represents that the associated objects before and after it are in an "or" relationship, but it can also represent an "and / or" relationship, which can be understood according to the context before and after it.

[0145] In the present application, "at least one" means one or more, and "multiple" means two or more. "At least one of the following" or the like means any combination of the items, including any combination of single or multiple items. For example, at least one of a, b, or c can represent a, b, c, a-b, a-c, b-c, or a-b-c, where a, b, and c can be single or multiple.

[0146] It should be understood that in various embodiments of the present application, the size of the sequence number of the above-described processes does not mean the order of execution, and the execution order of the processes should be determined according to their functions and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0147] Those skilled in the art can clearly understand that the units and algorithm steps of each example described in combination with the embodiments disclosed herein can be realized by electronic hardware or a combination of computer software and electronic hardware. Whether the functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present application.

[0148] Those skilled in the art can clearly understand that, for the convenience and brevity of the description, the specific working processes of the devices, apparatuses and units described above can refer to the corresponding processes in the foregoing method embodiments, which will not be repeated here.

[0149] In several embodiments provided by the present application, it should be understood that the disclosed devices, apparatuses and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely schematic, for example, the division of the units is only a logical function division, and actual implementation can have another division manner, for example, multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between the units shown or discussed can be indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0150] The units described as separate components can or can not be physically separated, and the components shown as units can or can not be physical units, that is, they can be located in one place, or can be distributed on multiple network units. Part or all of the units can be selected according to actual needs to achieve the purpose of the embodiment scheme.

[0151] In addition, each functional unit in each embodiment of the present application can be integrated into a processing unit, or each unit can exist physically independently, or two or more units can be integrated into one unit.

[0152] If the functions are realized in the form of software function units and sold or used as independent products, they can be stored in a computer readable storage medium. Based on this understanding, the technical solutions of the present application or the parts of the present application that essentially contribute to the prior art or the parts of the technical solutions can be embodied in the form of software products. The computer software product is stored in a storage medium and includes a plurality of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in the various embodiments of the present application. The aforementioned storage medium includes a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and various media that can store program codes.

[0153] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A method for identifying fall-prone rock masses based on dual indicators, characterized in that, The method includes: S1. Obtain the cohesion, internal friction angle, density, initial rock bridge length, self-weight, thickness, length, tensile strength, natural vibration frequency, friction coefficient on the structural surface, and effective normal stress on the structural surface of the rock mass to be identified. S2. Calculate the damping ratio of the damaged, falling rock mass based on the friction coefficient and effective normal stress on the structural surface. S3. Based on the obtained natural vibration frequency, initial rock bridge length and calculated damping ratio, calculate the rock bridge length of the falling unstable rock mass at different times after damage. S4. Calculate the shear safety factor of the falling rock mass based on the cohesion, effective normal stress on the structural surface, internal friction angle, density, length, thickness, and rock bridge length. S5. Calculate the tensile-shear safety factor of the falling rock mass based on tensile strength, cohesion, effective normal stress on the structural surface, internal friction angle, density, length, thickness, and rock bridge length. S6. Calculate the dynamic safety factor and weak stability dynamic safety factor of the falling rock mass based on the shear safety factor and tensile shear safety factor of the falling rock mass; S7. Based on the dynamic safety factor and the weak stability dynamic safety factor, according to the preset identification rules, the falling rock mass to be identified is identified as a falling rock mass, and the identification result is obtained. Wherein, S3 includes: Based on the obtained natural vibration frequency, the calculated damping ratio, and the following formula (2), the length of the rock bridge of the falling rock mass at different times after damage is calculated: (2) Among them, l i Let l0 be the length of the rock bridge of the collapsing rock mass at time i, l0 be the initial length of the rock bridge of the collapsing rock mass, and f be the length of the rock bridge. i Let fi be the natural vibration frequency of the falling rock mass at time i, and f0 be the natural vibration frequency of the falling rock mass at the initial time. Let be the damping ratio of the falling rock mass at time i. The damping ratio of the initial falling rock mass; Wherein, S4 includes: The shear safety factor of the falling rock mass is calculated based on the cohesion, effective normal stress on the structural surface, internal friction angle, density, length, thickness, rock bridge length, and the following formula (3): (3) Among them, F si Let be the shear safety factor of the falling rock mass at time i, and c be the cohesion of the falling rock mass. The effective normal stress on the structural surface of the falling rock mass. The internal friction angle of the falling rock mass. Let g be the density of the falling rock mass, g be the acceleration due to gravity, H be the length of the falling rock mass, L be the thickness of the falling rock mass, and l be the density of the falling rock mass. i Let be the length of the rock bridge of the falling rock mass at time i.

2. The method for identifying fall-type unstable rock masses based on dual indicators according to claim 1, characterized in that, The damping ratio of the damaged, falling rock mass in S2 is calculated based on the friction coefficient and effective normal stress on the structural surface, including: Based on the friction coefficient, effective normal stress on the structural surface, and the following formula (1), the damping ratio of the damaged, falling rock mass is calculated: (1) in, The damping ratio of a falling rock mass. Let be the friction coefficient on the structural surface, N be the effective normal stress on the structural surface, s be the total displacement of the falling rock mass structure in a single cycle, and E be the total energy of the falling rock mass structure system. This is the damping loss factor.

3. The method for identifying fall-type unstable rock masses based on dual indicators according to claim 1, characterized in that, The tensile-shear safety factor of the falling rock mass is calculated based on tensile strength, cohesion, effective normal stress on the structural surface, internal friction angle, density, length, thickness, and rock bridge length, including: Based on the tensile strength, cohesion, effective normal stress on the structural surface, internal friction angle, density, length, thickness, rock bridge length, and the following formula (4), calculate the tensile-shear safety factor of the falling rock mass: (4) Among them, F ti R is the tensile-shear safety factor for the falling rock mass at time i. t denoted as ρ, where ρ is the tensile strength at the crack in the collapsed rock mass, and c is the cohesion of the collapsed rock mass. The effective normal stress on the structural surface of the falling rock mass. The internal friction angle of the falling rock mass. Let g be the density of the falling rock mass, g be the acceleration due to gravity, H be the length of the falling rock mass, L be the thickness of the falling rock mass, and l be the density of the falling rock mass. i Let be the length of the rock bridge of the falling rock mass at time i.

4. The method for identifying fall-type unstable rock masses based on dual indicators according to claim 3, characterized in that, S6 calculates the dynamic safety factor and weak stability dynamic safety factor of the falling rock mass based on the shear safety factor and tensile shear safety factor of the falling rock mass, including: S61. Calculate the dynamic safety factor of the falling rock mass based on the shear safety factor, tensile-shear safety factor, and the following formula (5): (5) Wherein, DSF is the dynamic safety factor for a falling rock mass, and F si Let F be the shear safety factor of the falling rock mass at time i. ti Let i be the tensile-shear safety factor for the falling rock mass; S62. Calculate the weak stability dynamic safety factor of the falling rock mass based on the shear safety factor, tensile-shear safety factor, and the following formula (6): (6) Wherein, WDSF is the weak stability dynamic safety factor of the falling rock mass, F si Let F be the shear safety factor of the falling rock mass at time i. ti Let be the tensile-shear safety factor of the falling rock mass at time i.

5. The method for identifying fall-type unstable rock masses based on dual indicators according to claim 1, characterized in that, S7, based on the dynamic safety factor and the weak stability dynamic safety factor, and according to preset identification rules, identifies the falling rock mass to be identified as a falling rock mass, and obtains the identification result, including: The calculated dynamic safety factor DSF and the weak stability dynamic safety factor WDSF are analyzed. When both DSF and WDSF are greater than or equal to 1, the falling rock mass is determined to be in a strongly stable stage, and the falling rock mass is a stable rock mass. When DSF is greater than or equal to 1 and WDSF is less than 1, the falling rock mass is determined to be in a weakly stable stage, and the falling rock mass is a dangerous rock mass. When both DSF and WDSF are less than 1, the falling rock mass is determined to have entered the accelerated failure stage, and the falling rock mass collapses.

6. A dual-index-based device for identifying falling rock masses, wherein the dual-index-based device is used to implement the dual-index-based method for identifying falling rock masses as described in any one of claims 1-5, characterized in that, The device includes: The acquisition module is used to acquire the cohesion, internal friction angle, density, initial rock bridge length, self-weight, thickness, length, tensile strength, natural vibration frequency, friction coefficient on the structural surface, and effective normal stress on the structural surface of the rock mass to be identified. The first determining module is used to calculate the damping ratio of the damaged falling rock mass based on the friction coefficient and effective normal stress on the structural surface. The second determining module is used to calculate the length of the rock bridge of the falling rock mass at different times after damage, based on the acquired natural vibration frequency, the initial rock bridge length and the calculated damping ratio. The third determining module is used to calculate the shear safety factor of the falling unstable rock mass based on the cohesion, effective normal stress on the structural surface, internal friction angle, density, length, thickness and rock bridge length; The fourth determining module is used to calculate the tensile-shear safety factor of the falling unstable rock mass based on tensile strength, cohesion, effective normal stress on the structural surface, internal friction angle, density, length, thickness, and rock bridge length. The fifth determining module is used to calculate the dynamic safety factor and weak stability dynamic safety factor of the falling rock mass based on the shear safety factor and tensile shear safety factor of the falling rock mass; The identification module is used to identify the falling rock mass based on the dynamic safety factor and the weak stability dynamic safety factor, according to the preset identification rules, and obtain the identification result.

7. A device for identifying falling rock masses, characterized in that, The fall-type unstable rock mass identification equipment includes: processor; A memory storing computer-readable instructions that, when executed by the processor, implement the method as described in any one of claims 1 to 5.

8. A computer-readable storage medium, characterized in that, The computer-readable storage medium contains program code that can be invoked by a processor to execute the method as described in any one of claims 1 to 5.

Images