A method for determining impact hazard based on the cuttings volume boundary equation

Abstract

The present invention belongs to the field of mine dynamic disaster monitoring and early warning, and specifically relates to a method for determining the impact hazard based on the cuttings volume boundary equation, which comprises the following steps: S10 calibrating the normal cuttings volume of the working location to be determined; S20 arranging boreholes at multiple measuring points of the working location to be determined, and measuring the actual cuttings volume of the boreholes at each measuring point at different borehole depths, while recording the dynamic effect phenomena occurring during the borehole drilling process and the corresponding borehole depths; S30 calculating the cuttings powder rate index corresponding to different borehole depth-to-heading height ratios of the boreholes at each measuring point; S40 determining the cuttings powder rate index boundary equation; S50 determining the area types corresponding to each cuttings powder rate index at different borehole depth-to-heading height ratios; S60 comprehensively determining the impact hazard of the working location according to the cuttings powder rate indices of the boreholes at each measuring point at different borehole depth-to-heading height ratios. The present invention can effectively improve the accuracy of determining the impact hazard by the cuttings method and reduce the possibility of misjudgment.

Description

Technical Field

[0001] The present invention belongs to the field of mine dynamic disaster monitoring and early warning, and specifically relates to a method for determining impact hazard based on a drilling cuttings volume limit equation. Background Technique

[0002] With the increase of coal mining depth, rock burst disasters occur frequently, seriously threatening the safety of people's lives and property. The drilling cuttings method is a method for determining impact hazard by constructing drill holes at the working site and judging the impact hazard according to the amount of drilling cuttings discharged during the drilling process and its variation law and related dynamic effects. The theoretical and experimental research on the drilling cuttings method began in the 1960s. Petukhov considered the swelling phenomenon in the inelastic deformation zone around the drill hole, introduced a loosening coefficient, and obtained the relationship between the drilling cuttings volume and the coal body stress based on the Mohr-Coulomb strength criterion. Brona and Katsuhiko Sugawara calculated the radius of the inelastic zone according to the Kastner equation or the modified Fenner formula, and finally obtained the relationship between the total drilling cuttings volume and the coal body stress. Zhao Benjun et al. considered the strain softening property of the coal body and the additional drilling cuttings volume generated by inelastic deformation, and obtained the functional relationship between the coal body stress and the drilling cuttings volume. With the efforts of a series of coal workers, the national standard for the drilling cuttings method has been formulated in China, and the drilling cuttings method is used as a method for determining impact hazard and a means for testing the effect of danger removal.

[0003] The drilling cuttings method uses the drilling powder rate index to determine the impact hazard of the working site. However, the drilling powder rate index involves the measurement of the normal drilling cuttings volume, and the normal drilling cuttings volume needs to be measured in an area without mining and geological structure influence. Due to the complex geological and mining conditions, it is difficult to accurately measure, resulting in a large error in the drilling powder rate index and a low accuracy of determining impact hazard by the drilling cuttings method.

[0004] Therefore, it is necessary to develop a method for determining impact hazard that weakens the influence of the normal drilling cuttings volume to improve the accuracy of determining impact hazard by the drilling cuttings method. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a method for determining impact hazard based on a drilling cuttings volume limit equation for the measurement error of the normal drilling cuttings volume. The drilling cuttings volume limit equation is obtained by regression fitting of the actual drilling cuttings volume, and it is mutually complementary with the drilling powder rate index to jointly determine the impact hazard of the working site, so as to improve the accuracy of determining impact hazard by the drilling cuttings method.

[0006] To solve the above technical problem, the technical solution adopted by the present invention is: a method for determining impact hazard based on a drilling cuttings volume limit equation, including the following steps:

[0007] S10 Calibrate the normal drilling cuttings volume of the working site to be determined;

[0008] At k measuring points of the working location to be determined, boreholes are respectively arranged, and the actual drill cuttings volume a at different borehole depths j of the boreholes at each measuring point is measured ij , where i is the measuring point serial number, and at the same time, the dynamic effect phenomena occurring during the borehole drilling process and the corresponding borehole depths are recorded;

[0009] S30 According to the actual drill cuttings volume a ij and the normal drill cuttings volume, the drill powder rate index corresponding to different borehole depth-to-heading height ratios of the boreholes at each measuring point is calculated;

[0010] S40 According to the maximum and minimum values of the actual drill cuttings volume at different borehole depths of each measuring point, taking the borehole depth as the independent variable, and taking the maximum and minimum values of the actual drill cuttings volume as the dependent variables respectively, a drill cuttings volume limit equation is calculated by self-fitting, and it is converted into a drill powder rate index limit equation with the drill powder rate index as the dependent variable and the borehole depth-to-heading height ratio as the independent variable;

[0011] S50 According to the drill powder rate index limit equation, and in combination with the drill powder rate index index, determine the area type corresponding to each drill powder rate index at different borehole depth-to-heading height ratios:

[0012] If the drill powder rate index is both greater than the value corresponding to the drill powder rate index upper limit equation and greater than the drill powder rate index index, it is determined as an area with impact hazard;

[0013] If the drill powder rate index is both less than the value corresponding to the drill powder rate index upper limit equation and less than the drill powder rate index index; then it is determined as an area without impact hazard;

[0014] If the drill powder rate index is between the value corresponding to the drill powder rate index upper limit equation and the drill powder rate index index, it is determined as a potentially dangerous area of impact;

[0015] S60 According to the drill powder rate index of the boreholes at each measuring point at different borehole depth-to-heading height ratios, comprehensively determine the impact hazard of the working location.

[0016] In the step S10, the specific method for calibrating the normal drill cuttings volume c j of the working location to be determined is as follows:

[0017] Arrange multiple boreholes in the area without mining disturbance and geological structure influence corresponding to the working location to be determined, the borehole depth reaches the original rock stress area, measure the drill cuttings volume per meter at each borehole depth of each borehole and calculate the average value, and take the average value of the drill cuttings volume per meter at each borehole depth as the normal drill cuttings volume c j at different borehole depths of the working location to be determined.

[0018] In the step S30, the calculation formula of the drill powder rate index is:

[0019] t ij =aij / c j ;

[0020] wherein, t ij represents the drill cuttings rate index corresponding to the i-th measurement point, a ij represents the actual drill cuttings amount corresponding to the i-th measurement point at the borehole depth of j, c j represents the normal drill cuttings amount at the borehole depth of j.

[0021] In the step S40, the method for fitting the upper limit equation of the drill cuttings amount is as follows: for each borehole depth j, 1 ≤ j ≤ m, where m represents the maximum borehole depth; respectively take the maximum values of the actual drill cuttings amounts of the existing k measurement points at each borehole depth to obtain the maximum values of the drill cuttings amounts corresponding to different borehole depths, that is:

[0022] a max1 = max{a 11 , a 21 ,..., a k1}

[0023] a max2 = max{a 12 , a 22 ,..., a k2}

[0024] ……

[0025] a maxj = max{a 1j , a 2j ,..., a kj}

[0026] ……

[0027] a maxm = max{a 1m , a 2m ,..., a km}

[0028] Taking the borehole depths (1, 2, …… j, ……, m) as independent variables and the corresponding maximum values of the actual drill cuttings amounts (a max1 , a max2 , …… a maxj , ……, a maxm ) as dependent variables, perform multiple fittings through various equations, and take the fitting equation when R 2 reaches the maximum value as the upper limit equation of the drill cuttings amount, that is:

[0029] A maxj = g1(j);

[0030] wherein, g1 represents the upper limit function of the drill cuttings amount, A maxjIndicates the upper limit value of the drill cuttings volume.

[0031] In the step S40, the method for fitting the lower limit equation of the drill cuttings volume is as follows: for each drilling depth j, where 1 ≤ j ≤ m, the minimum value of the drill cuttings volume at this drilling depth of the existing k measurement points is taken respectively to obtain the minimum value of the drill cuttings volume corresponding to different drilling depths.

[0032] a min1 = min{a 11 , a 21 ,..., a k1}

[0033] a min2 = min{a 12 , a 22 ,..., a k2}

[0034] ……

[0035] a minj = min{a 1j , a 2j ,..., a kj}

[0036] ……

[0037] a minm = min{a 1m , a 2m ,..., a km}

[0038] Perform multiple fittings on the drilling depth and the corresponding minimum value of the drill cuttings volume, and take the fitting relationship formula when the R 2 is the maximum as the lower limit equation of the drill cuttings volume, that is:

[0039] A minj = g2(j);

[0040] Among them, g2 represents the upper limit function of the drill cuttings volume, and A minj represents the lower limit value of the drill cuttings volume.

[0041] When the boundary equation of the drill cuttings volume is obtained by self-fitting calculation, the fitting equations include linear, exponential, and logarithmic equations.

[0042] The boundary equation of the drill powder rate index transformed according to the boundary equation of the drill cuttings volume is:

[0043] B max (n) = g1(h·n) / c j ;

[0044] B min (n) = g1(h·n) / c j ;

[0045] Among them, B max (n) and B min (n) respectively represent the upper limit value and the lower limit value of the drill powder rate index at the hole depth-to-roadway height ratio n. g1 and g2 respectively represent the upper limit functions of the drill cuttings amount, h represents the roadway height of the working face, n represents the hole depth-to-roadway height ratio, and n = h / j.

[0046] Compared with the prior art, the present invention has the following beneficial effects: By fitting the actual drill cuttings amount data and combining it with the drill powder rate index index to refine the zoning, the influence brought by the measurement error of the normal drill cuttings amount is weakened, the accuracy of determining the impact risk by the drill cuttings method can be effectively improved, and the possibility of misjudgment can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 It is a schematic flow chart of a method for determining impact risk based on a drill cuttings amount limit equation provided by an embodiment of the present invention;

[0048] Figure 2 It is a schematic diagram of the impact risk zoning obtained in an embodiment of the present invention;

[0049] Figure 3 It is the impact risk determination result obtained in an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0050] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0051] As Figure 1 shown, an embodiment of the present invention provides a method for determining impact risk based on a drill cuttings amount limit equation, including the following steps:

[0052] S10 Calibrate the normal drill cuttings amount of the working location to be determined.

[0053] Specifically, the specific method for calibrating the normal drill cuttings amount c j is as follows:

[0054] Arrange a plurality of drill holes in the area without mining disturbance and geological structure influence corresponding to the working location to be determined. The drill hole depth reaches the original rock stress area. Measure the drill cuttings amount per meter at each drill hole depth of each drill hole and calculate the average value. Take the average value of the drill cuttings amount per meter at each drill hole depth as the normal drill cuttings amount c j of the working location to be determined.

[0055] In this process, first, more than 5 borehole measuring points are arranged in the normal stress area of the working point to be determined, the cuttings volume per meter of each borehole is measured and recorded, and finally, the average value of the cuttings volume per meter is calculated based on the cuttings volume per meter at the corresponding borehole depths of each borehole, and the normal cuttings volume per meter c of this working location is obtained. j It should be noted that the measurement result of the normal cuttings volume is only applicable to the corresponding working location. When obvious changes occur in the geological conditions within this working location, it is necessary to re-calibrate the normal cuttings volume.

[0056] At k measuring points in the working location to be determined, boreholes are respectively arranged, and the actual cuttings volume a of the boreholes at each measuring point at different borehole depths j is measured. ij Here, i is the measuring point serial number, and at the same time, the dynamic effect phenomena occurring during the borehole drilling process and the corresponding borehole depths are recorded. Among them, the dynamic effect refers to phenomena such as weak drilling suction and drill jamming occurring during the borehole construction process.

[0057] Among them, on the premise of ensuring safety, the boreholes should be arranged at locations where impact hazards may occur according to the speculation. The recommended borehole spacing and monitoring time are shown in Table 1, and the borehole spacing and monitoring time are appropriately adjusted according to the pre-evaluated impact hazard level and geological conditions of the working location to be measured.

[0058] Table 1 Recommended monitoring parameters of borehole cuttings method

[0059]

[0060] S30 Calculate the corresponding drill powder rate index of the boreholes at each measuring point at different ratios of borehole depth to roadway height according to the actual cuttings volume a ij and the normal cuttings volume.

[0061] In the said step S30, the calculation formula of the drill powder rate index is:

[0062] t ij = a ij / c j ; (1)

[0063] Among them, t ij represents the drill powder rate index corresponding to the i-th measuring point, a ij represents the actual cuttings volume corresponding to the i-th measuring point at the borehole depth of j, and c j represents the normal cuttings volume at the borehole depth of j.

[0064] Among them, the ratio of borehole depth to roadway height n is the ratio of the borehole depth j to the roadway height h, that is, n = j / h, and the drill powder rate index is the ratio of the actual cuttings volume a ij to the normal cuttings volume c j , that is, a ij / c jThe drill powder rate index indicators for different ratios of borehole depth to roadway height are shown in Table 2.

[0065] Table 2 Drill powder rate index indicators for evaluating the impact risk at the working site

[0066]

[0067] S40 Based on the maximum and minimum values of the actual drill cuttings at each measuring point under different borehole depths, taking the borehole depth as the independent variable and the maximum and minimum values of the actual drill cuttings as the dependent variables respectively, self-fitting calculation is carried out to obtain the drill cutting amount limit equation, and it is transformed into a drill powder rate index limit equation with the drill powder rate index as the dependent variable and the ratio of borehole depth to roadway height as the independent variable.

[0068] The following introduces the method for fitting the upper limit equation and lower limit equation of the drill cutting amount.

[0069] Assume that the maximum borehole depth is m, then the drill cutting amount data of the i-th measuring point can be expressed as: [a i1 , a i2 ,..., a im .

[0070] For each borehole depth j, 1 ≤ j ≤ m, respectively take the maximum values of the actual drill cuttings at the existing k measuring points under each borehole depth to obtain the maximum values of the drill cuttings corresponding to different borehole depths, that is:

[0071] a max1 =max{a 11 , a 21 ,..., a k1}; (2)

[0072] a max2 =max{a 12 , a 22 ,..., a k2}; (3)

[0073] ……

[0074] a maxj =max{a 1j , a 2j ,..., a kj}; (4)

[0075] ……

[0076] a maxm =max{a 1m , a 2m ,..., a km}; (5)

[0077] Taking the drilling depth (1, 2, …… j, ……, m) as the independent variable (j), and the corresponding maximum actual drill cuttings amount (a max1 , a max2 , …… a maxj , ……, a maxm ) as the dependent variable, that is, a maxj = f1(j). Perform linear, exponential, logarithmic and other equation fittings on the relationship between the two, and take the fitting equation when the R 2 reaches the maximum value as the upper limit equation of the drill cuttings amount, that is:

[0078] A maxj = g1(j); (6)

[0079] Among them, g1 represents the upper limit function of the drill cuttings amount, and A maxj represents the upper limit value of the drill cuttings amount.

[0080] Similarly, for each drilling depth j, 1 ≤ j ≤ m, respectively take the minimum value of the drill cuttings amount of the existing k measurement points at this drilling depth, and obtain the minimum value of the drill cuttings amount corresponding to different drilling depths, that is:

[0081] a min1 = min{a 11 , a 21 , ..., a k1}; (7)

[0082] a min2 = min{a 12 , a 22 , ..., a k2}; (8)

[0083] ……

[0084] a minj = min{a 1j , a 2j , ..., a kj}; (9)

[0085] ……

[0086] a minm = min{a 1m , a 2m , ..., a km}; (10)

[0087] Taking the drilling depth (1, 2, …… j, ……, m) as the independent variable (j), and the corresponding minimum actual drill cuttings amount (a min1 , a min2 , …… a minj , ……, a minm)As the dependent variable, there is a minj = f2(j), and various equations such as linear, exponential, and logarithmic equations are used to fit the relationship between the two, and the fitting equation when taking the maximum value of R 2 is used as the upper limit equation of the drill cuttings amount, that is:

[0088] A minj = g2(j); (11)

[0089] Among them, g2 represents the upper limit function of the drill cuttings amount, and A minj represents the lower limit value of the drill cuttings amount.

[0090] Specifically, according to equations (6) and (11), divide both sides of the equation by the normal drill cuttings amount c per meter j , and then use the hole depth - roadway height ratio n = j / h, and it can be transformed into a functional relationship between the drill powder rate index and the hole depth - roadway height ratio, that is, the drill powder rate index limit equation is obtained as:

[0091] B max (n) = g1(h·n) / c j ; (12)

[0092] B min (n) = g1(h·n) / c j ; (13)

[0093] Among them, B max (n) and B min (n) respectively represent the upper limit value and the lower limit value of the drill powder rate index under the hole depth - roadway height ratio n, g1 and g2 respectively represent the upper limit function of the drill cuttings amount, h represents the roadway height of the working face, and n represents the hole depth - roadway height ratio.

[0094] S50 Determine the area type corresponding to each drill powder rate index under different hole depth - roadway height ratios according to the drill powder rate index limit equation and in combination with the drill powder rate index index.

[0095] If the drill powder rate index is both greater than the value corresponding to the drill powder rate index upper limit equation and greater than the drill powder rate index index, that is: t ij > B max (n), and t ij > t, then it is determined as an area with impact risk;

[0096] If the drill powder rate index is both less than the value corresponding to the drill powder rate index upper limit equation and less than the drill powder rate index index, that is:

[0097] t ij < B min (n), and t ij < t, then it is determined as an area without impact risk;

[0098] If the drill powder rate index is between the value corresponding to the upper limit equation of the drill powder rate index and the drill powder rate index index, that is: min{B min (n), t} < t ij <max{B min (n), t}, it is determined as a potential impact hazard area;

[0099] S60 comprehensively determines the impact hazard of the working face according to the drill powder rate index of the boreholes at each measuring point under different hole depth - roadway height ratios.

[0100] Specifically, the impact hazard of the working face can be determined according to conservative or radical situations: when being more conservative, the drill powder rate index is determined as having an impact hazard in both the impact - hazard area and the potential impact - hazard area, and is determined as having no impact hazard only in the no - impact - hazard area; when being more radical, the drill powder rate index is determined as having no impact hazard in both the no - impact - hazard area and the potential impact - hazard area, and is determined as having an impact hazard only in the impact - hazard area or when there are dynamic effects such as sticking or sucking of the drill.

[0101] The following takes the transportation roadway of the 3208 working face in a certain mine as the working face to be determined to specifically illustrate the specific implementation method of the impact hazard determination method of the present invention. The specific steps are as follows:

[0102] Step 1: Measure the normal drill cuttings amount in the area without mining influence and geological structure influence near the working face. The measurement method is: near the working face in the area not affected by mining and excavation, a borehole is arranged every 10 - 30 m, and the borehole depth reaches the original rock stress area; five measuring points are sequentially selected, and the mass of the drill cuttings discharged per meter of the borehole at each of the five measuring points is recorded, and their average value is obtained. The normal drill cuttings amount at each depth is 2.4 kg / m.

[0103] Step 2: Construct boreholes at the working face to measure the actual drill cuttings amount. The measurement method is: at the two sides of the roadway 20 m behind the driving face of the transportation roadway of the 3208 working face, it is monitored once a week on average along with the driving. The daily driving footage is 1 - 3 m, that is, the average borehole spacing is 14 m. The borehole is in the middle of the roadway height, parallel to the bedding plane, perpendicular to the coal wall, the drill bit diameter is Φ42 mm, and the hole depth is 15 m. The actual drill cuttings amount at this working face is obtained, as shown in Table 3.

[0104] Table 3 Actual drill cuttings amount per meter of the driving face of the transportation roadway of the 3208 working face

[0105]

[0106] Step 3: According to the actual drill cuttings amount a ij and the normal drill cuttings amount c j , the drill powder rate index at different hole depth - roadway height ratios is obtained.

[0107] The roadway height of the driving face in the 3208 working face transportation roadway is 4.6 m. Referring to Table 2, the corresponding drilling depths when the drill powder rate index indicators are 1.5 and 3 are: 4.6×1.5 = 6.9 m, 4.6×3 = 13.8 m. The drill powder rate index at different ratios of drilling depth to roadway height is shown in Table 4.

[0108] Table 4 Drill powder rate index at different ratios of drilling depth to roadway height

[0109]

[0110] Step 4: Calculate the drill cuttings amount limit equation by self-fitting according to the actual drill cuttings amount. The calculation method is: for each drilling depth, take the maximum value of the drill cuttings amount at different measuring points at this drilling depth, that is:

[0111] a max8 = max{2.2, 2.3, 2.1, 2.5, 2.8, 2.4, 2.2, 2.6, 2.6, 2.6, 2.5, 2.5} = 2.8;

[0112] a max8 = max{2.2, 2.3, 2.1, 2.5, 2.8, 2.4, 2.2, 2.6, 2.6, 2.6, 2.5, 2.5} = 2.8;

[0113] a max9 = max{2, 2.5, 3.4, 2.3, 3.7, 2.6, 2.8, 2.5, 2.3, 3, 2.8, 2.8} = 3.7; ......

[0115] a max15 = max{4.5, 4.3, 5.4, 4.6, 5.6, 4, 3.9, 5.1, 4.6, 3.5, 5.7, 4.2} = 5.7;

[0116] Thus, the relationship between the maximum value of the drill cuttings amount and the drilling depth at different drilling depths is obtained:

[0117] A maxj = f1(j); (14)

[0118] Perform linear, exponential, logarithmic, etc. fitting on this relationship respectively, and the results are shown in Table 5.

[0119] Table 5 R values of different fitting methods 2

[0120]

[0121] Take the relationship formula when R 2 reaches the maximum value, which is the drill cuttings amount upper limit equation:

[0122] A maxj = 0.40j - 0.22; (15)

[0123] Similarly, the lower limit equation of the drill cuttings amount can be obtained:

[0124] A minj = 1.05e 0.08j ; (16)

[0125] Transform the boundary equation into the form of the drill powder rate index and the ratio of hole depth to roadway height:

[0126] B max (n) = 0.77(j / h) - 0.09; (17)

[0127] B min (n) = 0.44e 0.37(j / h) ; (18)

[0128] Step Five: Refine the rock burst danger area according to the boundary equation and in combination with the drill powder rate index. The results are as Figure 2 shown, where the pink area is the area with rock burst danger, the yellow area is the potential rock burst danger area, and the blue area is the area without rock burst danger.

[0129] Step Six: Determine the rock burst danger of the working place according to the conservative or radical situation. As Figure 3 known, there are individual measuring points in the area with rock burst danger, and there are weak phenomena of drill sticking and drill jamming during the drilling construction process, accompanied by weak sounds. Therefore, it is determined that there is rock burst danger at this working place.

[0130] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for determining impact hazard based on the cuttings volume boundary equation, characterized in that, Including the following steps: S10 Calibrate the normal drill cuttings volume at the working location to be determined; At k measuring points at the work location to be determined, boreholes are respectively arranged, and the actual drill cuttings amount of each borehole at different borehole depths j is measured a ij , i is the measuring point serial number, and at the same time, the dynamic effect phenomena occurring during the borehole drilling process and the corresponding borehole depths are recorded; S30 Calculate the drill powder rate index corresponding to the boreholes at each measuring point at different hole depth-to-roadway height ratios according to the actual drill cuttings volume a ij and the normal drill cuttings volume; S40 According to the maximum and minimum values of the actual drill cuttings volume at each measuring point at different drilling depths, taking the drilling depth as the independent variable and the maximum and minimum values of the actual drill cuttings volume as the dependent variables respectively, self-fittingly calculate the drill cuttings volume limit equation, and convert it into a drill powder rate index limit equation with the drill powder rate index as the dependent variable and the hole depth to roadway height ratio as the independent variable; S50 According to the drill powder rate index limit equation and in combination with the drill powder rate index index, determine the area type corresponding to each drill powder rate index at different hole depth to roadway height ratios: If the drill powder rate index is both greater than the value corresponding to the upper limit equation of the drill powder rate index and greater than the drill powder rate index index, it is determined as an area with impact danger; If the drill powder rate index is both less than the value corresponding to the upper limit equation of the drill powder rate index and less than the drill powder rate index index, it is determined as an area without impact danger; If the drill powder rate index is between the value corresponding to the upper limit equation of the drill powder rate index and the drill powder rate index index, it is determined as a potentially dangerous area for impact; S60 According to the drill powder rate index of the drill holes at each measuring point at different hole depth to roadway height ratios, comprehensively determine the impact hazard of the working location.

2. The impact hazard determination method based on the cuttings volume boundary equation according to claim 1, characterized in that, In the step S10, calibrate the normal drill cuttings volume at the work location to be determined c j The specific method is as follows: Arrange multiple boreholes in the area without mining disturbance and geological structure influence corresponding to the work location to be determined. The depth of the boreholes reaches the virgin stress area. Measure the cuttings per meter at each borehole depth of each borehole and calculate the average value. Take the average value of the cuttings per meter at each borehole depth as the normal cuttings volume at different borehole depths of the work location to be determined c j 。 3. The impact hazard determination method based on the cuttings volume boundary equation according to claim 1, characterized in that, In the step S30, the calculation formula of the drill powder rate index is: t ij = a ij / c j ， Among them, t ij represents the drill powder rate index corresponding to the i-th measurement point, a ij represents the actual drill cuttings volume corresponding to the i-th measurement point at the borehole depth of j ，c j represents the normal drill cuttings volume at the borehole depth of j.

4. The impact hazard determination method based on the cuttings volume boundary equation according to claim 1, characterized in that, In the step S40, the method for fitting the upper limit equation of the drill cuttings amount is as follows: for each drilling depth j , 1 ≤ j ≤ m , where m represents the maximum drilling depth; respectively take the maximum values of the actual drill cuttings amounts of the existing k measuring points at each drilling depth to obtain the maximum values of the drill cuttings amounts corresponding to different drilling depths, that is: a max1 = max{ a 11 , a 21 , ..., a k1} a max2 = max{ a 12 , a 22 , ..., a k2} …… a maxj = max{ a 1j , a 2j , ..., a kj} …… a maxm = max{ a 1m , a 2m , ..., a km} Take the drilling depth j as the independent variable, and the corresponding maximum actual drill cuttings volume a maxj as the dependent variable. Conduct multiple fittings through various equations, and take R 2 the fitting equation at the maximum value as the upper limit equation of the drill cuttings volume, that is: A maxj = g 1( j )； Among them, g 1 represents the upper limit function of the drill cuttings volume, and A maxj represents the upper limit value of the drill cuttings volume.

5. A method for determining the impact hazard based on the cuttings volume limit equation according to claim 1, characterized in that, In the step S40, the method for fitting the lower limit equation of the drill cuttings volume is as follows: for each drilling depth j , 1 ≤ j ≤ m , respectively take the minimum values of the drill cuttings volume at the existing k measuring points at this drilling depth, and obtain the minimum values of the drill cuttings volume corresponding to different drilling depths. a min1 =min{ a 11 , a 21 , ..., a k1} a min2 = min{ a 12 , a 22 , ..., a k2} …… a minj = min{ a 1j , a 2j , ..., a kj} …… a minm = min{ a 1m , a 2m , ..., a km} Perform multiple fittings on the drilling depth and the corresponding minimum value of the drill cuttings amount, and take R 2 the fitting relation formula at the maximum value as the lower limit equation of the drill cuttings amount, that is: A minj = g 2( j )； wherein, g2 represents the upper limit function of the drill cuttings amount, A minj represents the lower limit value of the drill cuttings amount.

6. A method for determining the impact hazard based on the cuttings volume boundary equation according to claim 3 or 4, characterized in that When self-fittingly calculating the drill cuttings volume limit equation, the fitting equation includes linear, exponential, and logarithmic equations.

7. A method for determining impact hazard based on the cuttings volume boundary equation according to claim 1, characterized in that, The drill powder rate index limit equation obtained by converting according to the drill cuttings volume limit equation is: B max （ n ）= g 1( h · n ) / c j ； B min （ n ）= g 1( h · n ) / c j ； Among them, B max ( n ) and B min ( n ) respectively represent the upper limit value and the lower limit value of the drill powder rate index at the n drill powder rate index, g 1 and g 2 respectively represent the upper limit function of the drill cuttings amount, h represents the roadway height of the working face, n represents the hole depth to roadway height ratio, n = h / j.

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