Roadway anchor rod cooperative anti-interference strength dynamic evaluation method

Abstract

A dynamic evaluation method for the cooperative disturbance resistance strength of roadway anchor bolts is proposed, which uses a borehole inspection instrument or ultrasonic detection equipment to determine the boundary depth of the plastic deformation zone of the surrounding rock after roadway excavation. D p Based on historical data of mining intensity and real-time mine pressure monitoring results, the critical resistance depth was obtained. D r ; Measure the physical installation length of the anchor bolt from the tunnel wall to the end of the borehole. L ; Calculate the length safety margin ratio α Corrected effective anti-disturbance length L e Based on the coupling effect of the length safety margin ratio and the exposure ratio, the disturbance sensitivity level is comprehensively assessed; and the disturbance resistance reduction factor is selected based on the disturbance sensitivity level. K r ; Calculate the effective active support strength P e ;when P e ≥ P d If the disturbance sensitivity level is Level I or II, the current support scheme is deemed qualified; if the disturbance sensitivity level is Level III or... P e < P d If the current support scheme is deemed unqualified, the anchor bolt parameters need to be redesigned or the support structure strengthened. This method can accurately evaluate the cooperative disturbance resistance strength of roadway anchor bolts.

Description

Technical Field

[0001] This invention belongs to the field of coal mine roadway support technology, specifically relating to a dynamic evaluation method for the cooperative anti-disturbance strength of roadway anchor bolts. Background Technology

[0002] Rock bolt support technology is a core means of controlling surrounding rock in modern coal mine roadways, and its reliability directly affects the safety and efficiency of underground operations. Especially under deep mining conditions, high ground pressure and strong mining disturbances lead to a sharp deterioration in the stability of the surrounding rock, making the rock bolt support system the first line of defense against roadway deformation and instability. Current methods for evaluating support strength rely excessively on engineering experience and analogy, and are mainly based on the single indicator of preload. They lack a quantitative understanding of the synergistic mechanism between rock bolt length, spatial location, and the depth of surrounding rock disturbance, making it difficult to meet the needs of accurate and dynamic assessment of the rock bolt's anti-disturbance support strength under complex geological conditions.

[0003] Specifically, in the existing evaluation of support strength, the initial tension applied by the anchor bolt is generally regarded as the core metric for support effectiveness. This single-index orientation has revealed significant defects in practice: when anchor bolts of different lengths reach the same tension, the system judges that their support capabilities are equivalent. However, downhole observations have confirmed that there are order-of-magnitude differences in their timeliness in maintaining the stability of the surrounding rock and their ability to resist dynamic loads. This difference stems from two neglected mechanical mechanisms: (1) the effective range of the stress field is limited: the constraint stress formed by the short anchor bolt only acts on the shallow surface layer and cannot build a continuous bearing structure in the deep part of the surrounding rock, resulting in weak deformation reserve; (2) the integrity of the anchoring system is reduced: due to spatial limitations, the entire length of the short anchor bolt is more easily exposed to the action domain of mining disturbance waves, and the rock-bolt interface undergoes progressive damage under cyclic loads, eventually triggering a chain reaction of anchor failure. The above defects cause the roadway to lose its stability control capability under strong mining disturbance. Therefore, it is urgent to provide a dynamic evaluation method for the collaborative disturbance resistance strength of roadway anchor bolts. Summary of the Invention

[0004] To address the problems existing in the prior art, this invention provides a dynamic evaluation method for the collaborative disturbance resistance strength of roadway anchor bolts. This method is simple to implement and has low implementation costs. Based on the spatial matching relationship between the total length of the anchor bolts and the depth of surrounding rock disturbance, and combined with the damage characteristics of the plastic zone, it corrects the support strength, enabling accurate evaluation of the collaborative disturbance resistance strength of roadway anchor bolts. It can effectively solve the problem of systemic failure caused by the location disadvantage of short anchor bolts, and provide a scientific and quantitative dynamic decision-making tool for deep roadway support design.

[0005] To achieve the above objectives, the present invention provides a method for dynamic evaluation of the cooperative anti-disturbance strength of roadway anchor bolts, comprising the following steps;

[0006] Step 1: Conduct on-site surveys of key parameters to obtain the critical anti-interference depth and physical installation length;

[0007] S11: Use borehole inspection equipment or ultrasonic testing equipment to determine the boundary depth of the plastic deformation zone of the surrounding rock after tunnel excavation. D p ;

[0008] S12: Based on historical data of mine mining intensity and real-time mine pressure monitoring results, the critical disturbance resistance depth is obtained according to formula (1). D r ;

[0009] D r = K p × D p (1);

[0010] In the formula, K p This is the amplification factor for the impact of mining activities, with a value range of 1.2 to 1.5;

[0011] S13: Actual measured physical installation length of the anchor bolt from the tunnel wall to the end of the borehole. L ;

[0012] Step 2: Disturbance risk classification and disturbance immunity quantification;

[0013] S21: Calculate the length safety margin ratio according to formula (2) α ;

[0014] α=L / D r (2);

[0015] S22: Corrected effective anti-interference length L e When the anchor bolt is completely within the plastic zone, i.e. L ≤ D p At that time, the effective anti-interference length is obtained according to formula (3). L e When the anchor bolt passes through the plastic zone and enters the stable rock layer, that is... L > D p At that time, the effective anti-interference length is obtained according to formula (4). L e ;

[0016] L e = L × K d (3);

[0017] In the formula, Kd This is the reduction factor for the plastic zone;

[0018] L e = D p +0.5×( L-D p (4);

[0019] S23: Calculate the pole disturbance exposure ratio according to formula (5) or ;

[0020] or =( L-L e ) / L ×100% (5);

[0021] In the formula, ( L-L e () represents the length of the high-disturbance exposed section;

[0022] S24: Based on the length safety margin ratio α With exposure ratio or The coupling effect is used to comprehensively assess the disturbance sensitivity level;

[0023] when α ≥1.5 and or ≤15%, classified as Level I risk; when 1.2≤ α <1.5% or 15% < or ≤30%, classified as Level II risk; when α <1.2 or or >30%, classified as Level III risk;

[0024] Step 3: Dynamic adjustment of support strength and engineering decision-making;

[0025] S31: Select the anti-disturbance reduction factor based on the disturbance sensitivity level K r ;

[0026] When the risk level is Level I, take K r =1.0, no intensity reduction is applied; when it is a Level II risk, take... K r =0.75~0.95, K r Value varies with exposure ratio or Increases and decreases linearly; when the risk level is III, take K r =0.4~0.7, K r Value as a percentage of safety margin αDecrease in a step-like manner;

[0027] S32: Calculate the effective active support strength according to formula (6). P e ;

[0028] P e = T × K r (6);

[0029] In the formula, T The measured preload applied during anchor bolt installation;

[0030] S33: Safety assessment of the support system;

[0031] when P e ≥ P d Furthermore, if the disturbance sensitivity level is Level I or II, the current support scheme is deemed qualified; among which, P d Design the support strength for the tunnel;

[0032] If the disturbance sensitivity level is Level III or P e < P d If the current support scheme is deemed unqualified, the anchor bolt parameters need to be redesigned or the support structure strengthened.

[0033] As a preferred option, in step S12 of step one, the amplification factor of mining impact is determined by combining the coal seam mining depth and the intensity of mine pressure manifestation. K p The specific process is as follows:

[0034] In mines with a mining depth greater than 700m and subjected to intense mining, [the following is taken]: K p =1.5; In moderately active mines with a mining depth between 500 and 700 m, take K p =1.35; In weakly active mines with a mining depth of less than 500m, take... K p =1.2.

[0035] As a preferred option, in step S22 of step two, the plastic zone reduction coefficient is differentially assigned based on the structural integrity of the roof rock mass. K d The specific process is as follows:

[0036] When the roof rock mass is relatively fractured, take K d=0.6; when the top plate has relatively well-developed cracks but has not reached the fractured state, take K d =0.7; when the top plate is complete, take K d =0.8.

[0037] As a preferred embodiment, in step S24 of step two, when α <1.0 and or If the risk level is greater than 40%, it is classified as Level IV risk.

[0038] As a preferred option, in step S33 of step three, if the disturbance sensitivity level is level IV, the real-time alarm module of the roadway support system is triggered. Simultaneously, an emergency response plan including anchor bolt length supplementation is generated, and the emergency response plan must ensure the physical length of the anchor bolts. L 锚杆 ≥1.5 D r At the same time, it is necessary to ensure L e ≥0.8 D r .

[0039] This invention provides a dynamic evaluation method for the collaborative disturbance resistance strength of roadway anchor bolts. The method is based on a spatial matching mechanism between the total length of the anchor bolt and the depth of surrounding rock disturbance. It determines the boundary depth of the plastic zone of the surrounding rock through field measurements and defines the critical disturbance resistance depth in conjunction with mining intensity. The method innovatively introduces the concepts of length safety margin ratio and effective disturbance resistance length, quantifying the actual anchoring effectiveness of the anchor bolt traversing the plastic zone. It establishes a bolt disturbance exposure ratio model to accurately characterize the range of sections affected by strong mining. A disturbance sensitivity level classification system (low risk / medium risk / high risk / extremely high risk) is constructed using the above parameters, and a disturbance resistance reduction coefficient is dynamically selected accordingly. Finally, the measured pre-tightening force is multiplied by this coefficient to obtain the effective active support strength, achieving support qualification judgment and parameter optimization decision-making. This invention focuses on the synergistic disturbance resistance mechanism of anchor bolt length and preload, and for the first time establishes a two-factor coupling theory of spatial anchoring effectiveness, breaking through the cognitive limitations of the traditional "preload-only" evaluation system. It proposes a spatial disturbance resistance depth theory, revealing that the vulnerability of short anchor bolts is essentially due to insufficient effective anchoring depth by quantifying the spatial positional relationship between the anchor bolt end and the disturbance source. A disturbance exposure ratio model is established to accurately characterize the range of sections affected by strong mining, providing early warning of overall disturbance failure risk. A dynamic correction system for support strength is constructed, coupling the length safety margin and the disturbance exposure ratio into a grading index to achieve scientific reduction of support strength. Ultimately, a full-process dynamic evaluation method of "survey-grading-correction-decision" is formed, providing theoretical tools and engineering guidelines for deep tunnel support design.

[0040] Compared with the prior art, the present invention has the following advantages:

[0041] 1) Establish a spatial matching theory between anchor length and disturbance resistance depth; break through the limitations of the traditional single preload evaluation system, and for the first time incorporate the spatial matching relationship between the total anchor length and the critical disturbance resistance depth of the surrounding rock into the core of support strength evaluation. By quantifying the effective anchoring performance of anchors crossing the plastic zone, the systemic failure mechanism of short anchors due to positional disadvantage is revealed, providing a scientific basis for support design.

[0042] 2) Construct a dynamic classification system for disturbance risk based on two factors; innovatively couple the length safety margin ratio and the disturbance exposure ratio as two parameters to establish a three-level disturbance sensitivity level (low / medium / high / extremely high risk), accurately characterize the failure risk range of anchor bolts affected by strong mining, realize the quantitative classification and early warning of the support system's anti-disturbance capability, and significantly improve the comprehensiveness and timeliness of risk identification.

[0043] 3) An anchoring performance correction method based on surrounding rock damage characteristics is proposed; based on the differential weighted plastic zone reduction coefficient of the roof rock mass integrity, the effective disturbance length is dynamically corrected according to the strategy of correcting the interface damage of fractured rock mass and reducing the weakening of intact rock mass, thus solving the common problem of traditional methods ignoring the influence of surrounding rock damage on the weakening of anchoring interface.

[0044] 4) Achieve dynamic optimization decision-making for support strength; dynamically select the anti-disturbance reduction coefficient by the disturbance sensitivity level, and correct the measured pre-tightening force to the effective active support strength, forming a full-process decision chain of "exploration-grading-correction-judgment", which not only ensures the support reliability of roadways with strong disturbance, but also avoids the waste of resources caused by over-support, and provides technical support for safe and efficient mining in deep mines.

[0045] This method is simple to implement and has low implementation costs. Based on the spatial matching relationship between the total length of the anchor bolt and the depth of the surrounding rock disturbance, it combines the damage characteristics of the plastic zone to correct the support strength. It can achieve an accurate evaluation of the cooperative anti-disturbance strength of the roadway anchor bolts, effectively solve the problem of systemic failure caused by the location disadvantage of short anchor bolts, and provide a scientific and quantitative dynamic decision-making tool for the design of deep roadway support. Attached Figure Description

[0046] Figure 1 This is a flowchart of the present invention. Detailed Implementation

[0047] like Figure 1 As shown, the present invention provides a dynamic evaluation method for the cooperative anti-disturbance strength of roadway anchor bolts, including the following steps;

[0048] Step 1: Conduct on-site surveys of key parameters to obtain the critical anti-interference depth and physical installation length;

[0049] S11: Use borehole inspection equipment or ultrasonic testing equipment to determine the boundary depth of the plastic deformation zone of the surrounding rock after tunnel excavation.D p Boundary depth D p The critical depth at which plastic failure occurs due to damage to the surrounding rock during tunneling;

[0050] S12: Based on historical data of mine mining intensity and real-time mine pressure monitoring results, the critical disturbance resistance depth is obtained according to formula (1). D r Critical Disturbance Immunity Depth D r It is the minimum safety threshold to ensure that the anchor bolt system is protected from mining disturbances during the mining process;

[0051] D r = K p × D p (1);

[0052] In the formula, K p This is the amplification factor for the impact of mining activities, with a value range of 1.2 to 1.5;

[0053] S13: Actual measured physical installation length of the anchor bolt from the tunnel wall to the end of the borehole. L ;

[0054] Step 2: Disturbance risk classification and disturbance immunity quantification;

[0055] S21: Calculate the length safety margin ratio according to formula (2) α ; length safety margin ratio α Characterizes the coverage capability of the total length of the anchor bolt to the critical disturbance resistance depth;

[0056] α=L / D r (2);

[0057] S22: Corrected effective anti-interference length L e Effective anti-interference length L e This reflects the actual effective anchorage length of the anchor bolt within the plastic zone of the surrounding rock due to interface damage; when the anchor bolt is completely within the plastic zone, i.e. L ≤ D p At that time, the effective anti-interference length is obtained according to formula (3). L e When the anchor bolt passes through the plastic zone and enters the stable rock layer, that is... L > D p At that time, the effective anti-interference length is obtained according to formula (4). Le The effective anti-interference length L e This reflects the reduction characteristics of anchoring efficiency within the stable region;

[0058] L e = L × K d (3);

[0059] In the formula, K d This is the reduction factor for the plastic zone;

[0060] L e = D p +0.5×( L-D p (4);

[0061] S23: Calculate the pole disturbance exposure ratio according to formula (5) or Proportion of pole disturbance exposure or Characterizes the proportion of sections where anchor bolts are affected by strong mining;

[0062] or =( L-L e ) / L ×100% (5);

[0063] In the formula, ( L-L e () represents the length of the high-disturbance exposed section, indicating the actual failure risk section length of the anchor bolt located in the high-disturbance zone (plastic zone or stress fluctuation zone);

[0064] S24: Based on the length safety margin ratio α With exposure ratio or The coupling effect is used to comprehensively assess the disturbance sensitivity level;

[0065] when α ≥1.5 and or ≤15%, classified as Level I risk, indicating that the anchor bolt has sufficient length safety reserve and the proportion of the disturbed section is low; when 1.2≤ α <1.5% or 15% < or ≤30%, classified as Level II risk, with simultaneous warnings of insufficient length safety margin or excessively high proportion of disturbed segments; when α <1.2 or or If the failure rate is greater than 30%, it is classified as a Level III risk, indicating that the anchor bolts have a significant potential for failure.

[0066] Step 3: Dynamic adjustment of support strength and engineering decision-making;

[0067] S31: Select the anti-disturbance reduction factor based on the disturbance sensitivity level K r ;

[0068] When the risk level is Level I, take K r =1.0, no intensity reduction is applied; when it is a Level II risk, take... K r =0.75~0.95, K r Value varies with exposure ratio or Increases and decreases linearly; when the risk level is III, take K r =0.4~0.7, K r Value as a percentage of safety margin α Decrease in a step-like manner;

[0069] S32: The measured preload applied during anchor bolt installation. T Multiply by the disturbance rejection reduction factor K r The effective active support strength is calculated according to formula (6). P e Effective active support strength P e This reflects the actual support strength after adjustment for disturbance risk;

[0070] P e = T × K r (6);

[0071] In the formula, T The measured preload applied during anchor bolt installation;

[0072] S33: Safety assessment of the support system;

[0073] when P e ≥ P d Furthermore, if the disturbance sensitivity level is Level I or II, the current support scheme is deemed qualified; among which, P d Design the support strength for the tunnel;

[0074] If the disturbance sensitivity level is Level III or P e < P d If the current support scheme is deemed unqualified, the anchor bolt parameters need to be redesigned or the support structure strengthened.

[0075] As a preferred option, in step S12 of step one, the amplification factor of mining impact is determined by combining the coal seam mining depth and the intensity of mine pressure manifestation. K p The specific process is as follows:

[0076] In mines with a mining depth greater than 700m and subjected to intense mining, [the following is taken]: K p =1.5; In moderately active mines with a mining depth between 500 and 700 m, take K p =1.35; In weakly active mines with a mining depth of less than 500m, take... K p =1.2.

[0077] As a preferred option, in step S22 of step two, the plastic zone reduction coefficient is differentially assigned based on the structural integrity of the roof rock mass. K d The specific process is as follows:

[0078] When the roof rock mass is relatively fractured, take K d =0.6, reflecting the high damage rate of the anchorage interface caused by strong fractures; when the top plate fractures are relatively developed but have not reached the fractured state, take K d =0.7, corresponding to the influence of moderately developed bedding fractures; when the top plate is intact, take K d =0.8, which characterizes anchoring performance with low damage.

[0079] As a preferred embodiment, in step S24 of step two, when α <1.0 and or If the risk level is greater than 40%, it is classified as Level IV risk.

[0080] As a preferred option, in step S33 of step three, if the disturbance sensitivity level is level IV, the real-time alarm module of the roadway support system is triggered. Simultaneously, an emergency response plan including anchor bolt length supplementation is generated, and the emergency response plan must ensure the physical length of the anchor bolts. L 锚杆 ≥1.5 D r That is, the physical length of the anchor bolt L To increase to more than 1.5 times the critical immunity depth, while ensuring L e ≥0.8 D r That is, the effective anti-interference length. L e The depth should be no less than 0.8 times the critical disturbance resistance depth to ensure that the core anchoring section is located in stable rock strata.

[0081] This invention provides a dynamic evaluation method for the collaborative disturbance resistance strength of roadway anchor bolts. The method is based on a spatial matching mechanism between the total length of the anchor bolt and the depth of surrounding rock disturbance. It determines the boundary depth of the plastic zone of the surrounding rock through field measurements and defines the critical disturbance resistance depth in conjunction with mining intensity. The method innovatively introduces the concepts of length safety margin ratio and effective disturbance resistance length, quantifying the actual anchoring effectiveness of the anchor bolt traversing the plastic zone. It establishes a bolt disturbance exposure ratio model to accurately characterize the range of sections affected by strong mining. A disturbance sensitivity level classification system (low risk / medium risk / high risk / extremely high risk) is constructed using the above parameters, and a disturbance resistance reduction coefficient is dynamically selected accordingly. Finally, the measured pre-tightening force is multiplied by this coefficient to obtain the effective active support strength, achieving support qualification judgment and parameter optimization decision-making. This invention focuses on the synergistic disturbance resistance mechanism of anchor bolt length and preload, and for the first time establishes a two-factor coupling theory of spatial anchoring effectiveness, breaking through the cognitive limitations of the traditional "preload-only" evaluation system. It proposes a spatial disturbance resistance depth theory, revealing that the vulnerability of short anchor bolts is essentially due to insufficient effective anchoring depth by quantifying the spatial positional relationship between the anchor bolt end and the disturbance source. A disturbance exposure ratio model is established to accurately characterize the range of sections affected by strong mining, providing early warning of overall disturbance failure risk. A dynamic correction system for support strength is constructed, coupling the length safety margin and the disturbance exposure ratio into a grading index to achieve scientific reduction of support strength. Ultimately, a full-process dynamic evaluation method of "survey-grading-correction-decision" is formed, providing theoretical tools and engineering guidelines for deep tunnel support design.

[0082] Compared with the prior art, the present invention has the following advantages:

[0083] 1) Establish a spatial matching theory between anchor length and disturbance resistance depth; break through the limitations of the traditional single preload evaluation system, and for the first time incorporate the spatial matching relationship between the total anchor length and the critical disturbance resistance depth of the surrounding rock into the core of support strength evaluation. By quantifying the effective anchoring performance of anchors crossing the plastic zone, the systemic failure mechanism of short anchors due to positional disadvantage is revealed, providing a scientific basis for support design.

[0084] 2) Construct a dynamic classification system for disturbance risk based on two factors; innovatively couple the length safety margin ratio and the disturbance exposure ratio as two parameters to establish a three-level disturbance sensitivity level (low / medium / high / extremely high risk), accurately characterize the failure risk range of anchor bolts affected by strong mining, realize the quantitative classification and early warning of the support system's anti-disturbance capability, and significantly improve the comprehensiveness and timeliness of risk identification.

[0085] 3) An anchoring performance correction method based on surrounding rock damage characteristics is proposed; based on the differential weighted plastic zone reduction coefficient of the roof rock mass integrity, the effective disturbance length is dynamically corrected according to the strategy of correcting the interface damage of fractured rock mass and reducing the weakening of intact rock mass, thus solving the common problem of traditional methods ignoring the influence of surrounding rock damage on the weakening of anchoring interface.

[0086] 4) Achieve dynamic optimization decision-making for support strength; dynamically select the anti-disturbance reduction coefficient by the disturbance sensitivity level, and correct the measured pre-tightening force to the effective active support strength, forming a full-process decision chain of "exploration-grading-correction-judgment", which not only ensures the support reliability of roadways with strong disturbance, but also avoids the waste of resources caused by over-support, and provides technical support for safe and efficient mining in deep mines.

[0087] This method is simple to implement and has low implementation costs. Based on the spatial matching relationship between the total length of the anchor bolt and the depth of the surrounding rock disturbance, it combines the damage characteristics of the plastic zone to correct the support strength. It can achieve an accurate evaluation of the cooperative anti-disturbance strength of the roadway anchor bolts, effectively solve the problem of systemic failure caused by the location disadvantage of short anchor bolts, and provide a scientific and quantitative dynamic decision-making tool for the design of deep roadway support.

Claims

1. A dynamic evaluation method for the cooperative disturbance resistance strength of roadway anchor bolts, characterized in that, Includes the following steps; Step 1: Conduct on-site surveys of key parameters to obtain the critical anti-interference depth and physical installation length; S11: Use borehole inspection equipment or ultrasonic testing equipment to determine the boundary depth of the plastic deformation zone of the surrounding rock after tunnel excavation. D p ; S12: Based on historical data of mining intensity and real-time mine pressure monitoring results, the critical disturbance resistance depth is obtained according to formula (1). D r ; D r = K p × D p （1）； In the formula, K p This is the amplification factor for the impact of mining activities, with a value range of 1.2 to 1.5; S13: Actual measured physical installation length of the anchor bolt from the tunnel wall to the end of the borehole. L ; Step 2: Disturbance risk classification and disturbance immunity quantification; S21: Calculate the length safety margin ratio according to formula (2) α ; α=L / D r （2）； S22: Corrected effective anti-interference length L e When the anchor bolt is completely within the plastic zone, i.e. L ≤ D p At that time, the effective anti-interference length is obtained according to formula (3). L e When the anchor bolt passes through the plastic zone and enters the stable rock layer, that is... L > D p At that time, the effective anti-interference length is obtained according to formula (4). L e ; L e = L × K d （3）； In the formula, K d This is the reduction factor for the plastic zone; L e = D p +0.5×（ L-D p ） （4）； S23: Calculate the pole disturbance exposure ratio according to formula (5) η ; η =（ L-L e ） / L ×100% （5）； In the formula, ( L-L e () represents the length of the high-disturbance exposed section; S24: Based on the length safety margin ratio α With exposure ratio η The coupling effect is used to comprehensively assess the disturbance sensitivity level; when α ≥1.5 and η ≤15%, classified as Level I risk; When 1.2≤ α <1.5% or 15% < η ≤30%, classified as Level II risk; when α <1.2 or η >30%, classified as Level III risk; Step 3: Dynamic adjustment of support strength and engineering decision-making; S31: Select the anti-disturbance reduction factor based on the disturbance sensitivity level K r ; When the risk level is Level I, take K r =1.0, no strength reduction is applied; When the risk level is Level II, take K r =0.75~0.95, K r Value varies with exposure ratio η Increases and decreases linearly; when the risk level is III, take K r =0.4~0.7, K r Value as a percentage of safety margin α Decrease in a step-like manner; S32: Calculate the effective active support strength according to formula (6). P e ; P e = T × K r （6）； In the formula, T The measured preload applied during anchor bolt installation; S33: Safety assessment of the support system; when P e ≥ P d Furthermore, if the disturbance sensitivity level is Level I or II, the current support scheme is deemed qualified; among which, P d Design the support strength for the tunnel; If the disturbance sensitivity level is Level III or P e < P d If the current support scheme is deemed unqualified, the anchor bolt parameters need to be redesigned or the support structure strengthened.

2. The method for dynamic evaluation of the cooperative anti-disturbance strength of roadway anchor bolts according to claim 1, characterized in that, In step S12 of step one, the amplification factor of mining impact is determined by combining the coal seam mining depth and the intensity of mine pressure manifestation. K p The specific process is as follows: In mines with a mining depth greater than 700m and subjected to intense mining, [the following is taken]: K p =1.5; In moderately active mines with a mining depth between 500 and 700 m, take K p =1.35; In weakly active mines with a mining depth of less than 500m, take... K p =1.

2.

3. A dynamic evaluation method for the cooperative anti-disturbance strength of roadway anchor bolts according to claim 1 or 2, characterized in that, In step S22 of step two, the plastic zone reduction coefficient is differentially assigned based on the structural integrity of the roof rock mass. K d The specific process is as follows: When the roof rock mass is relatively fractured, take K d =0.6; when the top plate has relatively well-developed cracks but has not reached the fractured state, take K d =0.7; when the top plate is complete, take K d =0.

8.

4. The method for dynamic evaluation of the cooperative anti-disturbance strength of roadway anchor bolts according to claim 3, characterized in that, In step two, S24, when α <1.0 and η If the risk level is greater than 40%, it is classified as Level IV risk.

5. The method for dynamic evaluation of the cooperative anti-disturbance strength of roadway anchor bolts according to claim 4, characterized in that, In step S33 of step three, if the disturbance sensitivity level is level IV, the real-time alarm module of the roadway support system is triggered. At the same time, an emergency response plan including anchor bolt length supplementation is generated, and the emergency response plan needs to ensure the physical length of the anchor bolts. L 锚杆 ≥1.5 D r At the same time, it is necessary to ensure L e ≥0.8 D r .

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