High-stress water-rich soft rock multi-source monitoring construction parameter dynamic determination method

Abstract

The application relates to the technical field of underground engineering construction safety and surrounding rock control, in particular to a high-stress water-rich soft rock multi-source monitoring construction parameter dynamic determination method. In the high-stress water-rich soft rock multi-source monitoring construction parameter dynamic determination method, water disaster indexes and surrounding rock deformation indexes in the construction process of high-stress water-rich soft rock are jointly included in the construction parameter determination process, the construction parameters are determined without relying on the surrounding rock grade or construction experience, the pertinence and adaptability of the construction parameter determination are improved. The current construction cycle or monitoring period is comprehensively judged through a water disaster risk index and a deformation risk index, the water-rich state of the working face, water discharge persistence, soft rock softening degree, surrounding rock deformation development and anchor rod anchor cable stress change can be reflected at the same time, and the water inrush, mud gushing, floor bulging, working face extrusion and support failure risks can be identified in time.

Description

Technical Field

[0001] This application relates to the field of underground engineering construction safety and surrounding rock control technology, and in particular to a method for dynamically determining construction parameters of high-stress, water-rich soft rock through multi-source monitoring. Background Technology

[0002] As underground engineering projects gradually extend to deeper levels, the problems of surrounding rock deformation and water hazards during construction in high-stress, water-rich soft rock are becoming increasingly prominent. This type of surrounding rock typically has characteristics such as low strength, well-developed fissures, easy softening upon contact with water, and significant rheological deformation. Under construction disturbances, it is prone to phenomena such as face extrusion, side convergence, roof subsidence, floor bulging, and rapid increase in stress on anchor bolts and cables. At the same time, groundwater entering the soft rock further weakens the surrounding rock strength, exacerbating the risks of surrounding rock deformation, floor bulging, and support failure.

[0003] Current construction methods typically employ measures such as advance water exploration, advance water discharge, advance grouting, short-cut construction, anchor mesh and shotcrete support, anchor cable reinforcement, and bottom plate sealing for control. However, the excavation advance, excavation step distance, advance water control range, grouting parameters, support parameters, and bottom plate control parameters largely rely on engineering experience for determination. This makes it difficult to reflect dynamic changes on-site, such as water pressure at the tunnel face, water output, the state of mud and water discharge from the borehole, changes in grouting pressure, deformation of the surrounding rock, and stress on anchor bolts and cables. This seriously affects the safety of underground engineering construction in high-stress, water-rich soft rock.

[0004] Therefore, there is a need to provide an improved technical solution that addresses the shortcomings of the existing technology. Summary of the Invention

[0005] The purpose of this application is to provide a method for dynamically determining construction parameters for multi-source monitoring of high-stress, water-rich soft rock, so as to solve or alleviate the problems existing in the above-mentioned prior art.

[0006] To achieve the above objectives, this application provides the following technical solution: A method for dynamically determining construction parameters for multi-source monitoring of high-stress, water-rich soft rock, the method comprising the following steps: Step 1: During the construction of underground engineering projects in high-stress, water-rich, soft rock, obtain multiple water hazard indicators and multiple deformation indicators within the current construction cycle or monitoring cycle. Step 2: Dimensionless processing is performed on multiple water hazard indicators. Based on the degree of impact of each water hazard indicator on construction safety, a weighted calculation is performed on the dimensionless water hazard indicators to obtain the water hazard risk index R for the current construction cycle or monitoring period. w ; Step 3: Perform dimensionless processing on multiple deformation indices. Based on the degree of influence of each deformation index on the stability of the surrounding rock and the safety of the support, perform weighted calculation on the dimensionless deformation indices to obtain the deformation risk index R for the current construction cycle or monitoring cycle. d ; Step 4: Establish a comprehensive construction risk index R c The correspondence between risk levels and water hazard risk index R; w and deformation risk index R d Determine the comprehensive construction risk index R for the current construction cycle or monitoring cycle. c To determine the risk level of the current construction cycle or monitoring cycle; Step 5, based on the current comprehensive construction risk index R c Determine the current construction control parameters; Step 6: Carry out the current construction according to the construction parameters determined in Step 5, and continue to collect water hazard indicators and surrounding rock deformation indicators during the construction process. Repeat Steps 1-5 to calculate the comprehensive construction risk index R. c Updates and adjustments will be made to subsequent construction parameters.

[0007] In the above-described method for dynamically determining construction parameters for multi-source monitoring of high-stress, water-rich soft rock, preferably, the multiple water hazard indicators include advanced borehole water pressure, water output per unit time, borehole water output attenuation rate, borehole mud-bearing water output status, and grouting pressure variation characteristics.

[0008] In the above-described method for dynamically determining construction parameters of high-stress, water-rich soft rock through multi-source monitoring, preferably, the deformation indices include the extrusion amount at the working face, the convergence amount of the two sidewalls, the settlement amount of the roof, the bulging amount of the floor, the bulging rate of the floor, and the stress growth rate of the anchor bolts or anchor cables.

[0009] In the above-described method for dynamically determining construction parameters for multi-source monitoring of high-stress, water-rich soft rock, preferably, the dimensionless processing includes two cases. For positive indicators where higher values ​​indicate higher risk, the following method is used for dimensionless processing: ; For contrarian indicators where larger values ​​correspond to lower risk, the following method is used for dimensionless processing: ; In the formula, X i Let X be the i-th measured index. i ′ represents the dimensionless index value, all of which are in the range of 0 to 1; X i,min and X i,max These are the minimum and maximum values ​​corresponding to the i-th indicator, respectively.

[0010] The method for dynamically determining construction parameters for multi-source monitoring of high-stress, water-rich soft rock, as described above, preferably includes the water hazard risk index R. w The calculation formula is: ; In the formula, A′ is the pre-drilling water pressure after dimensionless processing; B′ is the water output per unit time after dimensionless processing; η q ′ represents the borehole water attenuation rate after dimensionless processing. A smaller borehole water attenuation rate indicates stronger continuous water-rich fracture recharge and a higher risk of water damage. Therefore, (1-η) is used. q C′ is the water attenuation risk item in the water hazard risk index; C′ is the borehole mud-bearing water state index after dimensionless processing; D′ is the grouting pressure change characteristic index after dimensionless processing; a1, a2, a3, a4, and a5 are the weighting coefficients corresponding to the working face or advanced borehole water pressure, water output per unit time, water attenuation risk item, borehole mud-bearing water state, and grouting pressure change characteristic, respectively, and satisfy: a1+a2+a3+a4+a5=1.

[0011] The above-described method for dynamically determining construction parameters for multi-source monitoring of high-stress, water-rich soft rock, preferably includes the deformation risk index R. d The calculation formula is: ; In the formula, E′ is the extrusion amount of the tunnel face after dimensionless treatment, F′ is the convergence amount of the two sides after dimensionless treatment, G′ is the subsidence amount of the roof after dimensionless treatment, H′ is the bulging amount of the bottom plate after dimensionless treatment, I′ is the bulging rate of the bottom plate after dimensionless treatment, and J′ is the force growth rate of the anchor bolt or anchor cable after dimensionless treatment; b1, b2, b3, b4, b5, and b6 are the weight coefficients of the corresponding indicators, and satisfy: b1+b2+b3+b4+b5+b6=1.

[0012] The above-described method for dynamically determining construction parameters for multi-source monitoring of high-stress, water-rich soft rock, preferably includes the comprehensive construction risk index R. c The calculation formula is: ; In the formula: R c R is a comprehensive construction risk index. w R is the flood risk index. d It is the deformation risk index; and R w and R d All are dimensionless index values ​​in the range of 0 to 1.

[0013] The above-mentioned method for dynamically determining construction parameters for multi-source monitoring of high-stress, water-rich soft rock preferably sets three risk thresholds: a first risk threshold T1, a second risk threshold T2, and a third risk threshold T3, where T1 < T2 < T3. When R c When the risk level is less than T1, the current construction cycle or monitoring cycle is determined to be low-risk. When T1≤R c When the risk level is less than T2, the current construction cycle or monitoring cycle is determined to be at a medium risk level. When T2≤R c When the risk level is <T3, the current construction cycle or monitoring cycle is determined to be high-risk. When R c When the risk level is ≥T3, the current construction cycle or monitoring cycle is determined to be at an extremely high risk level.

[0014] The preferred method for dynamically determining construction parameters for multi-source monitoring of high-stress, water-rich soft rock, as described above, is to determine the overall construction control mode within the current construction cycle or monitoring cycle based on the comprehensive construction risk level. When the overall construction risk level is low, conventional construction, conventional advance water exploration and drainage, conventional support and conventional closed control mode are adopted. When the overall construction risk level is medium risk, a construction control mode is adopted that includes shortening the advance, strengthening advance water exploration and drainage, early support closure, and local drainage treatment. When the overall construction risk level is high, a construction control mode is adopted, which includes short advance, enhanced advanced grouting or water-blocking grouting, accelerated support closure, early control of the bottom plate, and reinforcement of anchor bolts and cables. When the overall construction risk level is extremely high, normal construction shall be suspended and measures such as advance water drainage and pressure reduction, face sealing, advance water blocking grouting, bottom corner locking, temporary sealing of the bottom slab, or reinforcement of support shall be taken. Construction shall be resumed after the overall construction risk is reduced.

[0015] In the above-mentioned method for dynamically determining construction parameters of high-stress, water-rich soft rock through multi-source monitoring, preferably, during the construction process, when there is continuous water inrush and mud surge, instability of the working face, rapid bulging of the bottom plate, obvious damage to the support structure, uncontrolled grouting, or a continuous increase in the deformation rate of the surrounding rock, the current construction cycle or monitoring cycle is directly judged as an extremely high risk level, and construction is suspended, and reinforced support measures are taken.

[0016] Compared with the closest prior art, the technical solution of this application has the following beneficial effects: In this method for dynamically determining construction parameters for multi-source monitoring of high-stress, water-rich soft rock, water hazard indicators and surrounding rock deformation indicators during the construction process of high-stress, water-rich soft rock are incorporated into the process of determining construction parameters. This avoids relying solely on the surrounding rock grade or construction experience to determine construction parameters, thereby improving the pertinence and adaptability of the determination of construction parameters.

[0017] By comprehensively judging the current construction cycle or monitoring cycle through the water hazard risk index and deformation risk index, it can simultaneously reflect the water-rich state of the working face, the continuity of water discharge, the degree of softening of soft rock when exposed to water, the development of surrounding rock deformation, and the stress changes of anchor bolts and cables. This is conducive to timely identification of risks such as water inrush, mudslide, bottom plate bulging, working face extrusion, and support failure.

[0018] Based on the comprehensive construction risk level, the tunneling advance, excavation step distance, advanced water control parameters, advanced grouting parameters, support parameters, and bottom plate control parameters are dynamically determined to enable timely implementation of measures such as short advance, strong water control, rapid support, and early closure under high-risk conditions, thereby improving the construction safety of underground engineering in high-stress, water-rich soft rock.

[0019] Finally, water hazard indicators and surrounding rock deformation indicators are collected in real time during construction to enable dynamic correction of construction parameters, allowing the construction parameters to be dynamically adjusted according to the water hazard status and the development of surrounding rock deformation. Attached Figure Description

[0020] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. Wherein: Figure 1 This is a flowchart illustrating a method for dynamically determining construction parameters for multi-source monitoring of high-stress, water-rich soft rock according to some embodiments of this application. Figure 2 This is a schematic diagram illustrating the risk level and construction parameter adjustment of the determination method provided according to some embodiments of this application. Detailed Implementation

[0021] The present application will now be described in detail with reference to the accompanying drawings and embodiments. Various examples are provided by way of interpretation and not by way of limitation. In fact, those skilled in the art will recognize that modifications and variations can be made to the present application without departing from the scope or spirit thereof. For example, a feature represented or described as part of one embodiment may be used in another embodiment to produce yet another embodiment. Therefore, it is desirable that the present application encompass such modifications and variations that fall within the scope of the appended claims and their equivalents.

[0022] In the following description, the terms "first / second / third" are used only to distinguish similar objects and do not represent a specific order of objects. It is understood that "first / second / third" may be interchanged in a specific order or sequence where permitted, so that the embodiments of this application described herein can be implemented in an order other than that illustrated or described herein.

[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. The terminology used herein is for the purpose of describing embodiments of this disclosure only and is not intended to limit this disclosure.

[0024] In the description of this application, the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," and "bottom," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and do not require that this application be constructed and operated in a specific orientation, and therefore should not be construed as limiting this application. The terms "connected," "linked," and "set up" used in this application should be interpreted broadly. For example, they can refer to fixed connections or detachable connections; direct connections or indirect connections through intermediate components; wired connections, radio connections, or wireless communication signal connections. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0025] The present application will now be described in detail with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in the embodiments of the present application can be combined with each other.

[0026] According to specific embodiments of this application, such as Figure 1-2 As shown, this application provides a method for dynamically determining construction parameters for multi-source monitoring of high-stress, water-rich soft rock. The method includes the following steps: Step 1: During the construction of underground engineering projects in high-stress, water-rich, soft rock, obtain multiple water hazard indicators and multiple deformation indicators within the current construction cycle or monitoring period.

[0027] Step 2: Dimensionless processing is performed on multiple water hazard indicators. Based on the degree of impact of each water hazard indicator on construction safety, a weighted calculation is performed on the dimensionless water hazard indicators to obtain the water hazard risk index R for the current construction cycle or monitoring period. w In this embodiment, the water hazard risk index R w The water hazard risk index R is calculated by weighting multiple dimensionless water hazard indicators to make the water hazard risk index R... w It can characterize the degree of development of water-rich fissures in front of the tunnel face and in the shallow surrounding rock, water pressure status, water outflow continuity, slurry diffusion status, and the risk of water-rich soft rock softening when exposed to water.

[0028] Step 3: Perform dimensionless processing on multiple deformation indices. Based on the degree of influence of each deformation index on the stability of the surrounding rock and the safety of the support, perform weighted calculation on the dimensionless deformation indices to obtain the deformation risk index R for the current construction cycle or monitoring cycle. dIn this embodiment, the deformation risk index R d The deformation risk index R is calculated by weighting multiple dimensionless deformation indices to make the deformation risk index R... d It can characterize the risks of face extrusion, side convergence, roof subsidence, floor bulging, and stress increase of anchor bolts or cables during construction in high-stress, water-rich soft rock.

[0029] Step 4: Establish a comprehensive construction risk index R c The correspondence between risk levels and water hazard risk index R; w and deformation risk index R d Determine the comprehensive construction risk index R for the current construction cycle or monitoring cycle. c This is to determine the risk level of the current construction cycle or monitoring cycle.

[0030] Step 5, based on the current comprehensive construction risk index R c Determine the current construction control parameters; in this embodiment, the construction parameters include tunneling advance, excavation step distance, length of advance water release hole, advance water control range, advance grouting length, grouting pressure, grouting volume, support lag distance, initial spraying closure time, bottom plate closure distance, anchor bolt and cable length, anchor bolt and cable spacing, anchor bolt and cable preload, bottom plate drainage parameters, bottom corner locking parameters, temporary support parameters, and suspension of construction or reinforcement treatment methods.

[0031] Step 6: Carry out the current construction according to the construction parameters determined in Step 5, and continue to collect water hazard indicators and surrounding rock deformation indicators during the construction process. Repeat Steps 1-5 to calculate the comprehensive construction risk index R. c Updates and adjustments will be made to subsequent construction parameters.

[0032] In this method for dynamically determining construction parameters for multi-source monitoring of high-stress, water-rich soft rock, water hazard indicators and surrounding rock deformation indicators during the construction process of high-stress, water-rich soft rock are incorporated into the process of determining construction parameters. This avoids relying solely on the surrounding rock grade or construction experience to determine construction parameters, thereby improving the pertinence and adaptability of the determination of construction parameters.

[0033] By comprehensively judging the current construction cycle or monitoring cycle through the water hazard risk index and deformation risk index, it can simultaneously reflect the water-rich state of the working face, the continuity of water discharge, the degree of softening of soft rock when exposed to water, the development of surrounding rock deformation, and the stress changes of anchor bolts and cables. This is conducive to timely identification of risks such as water inrush, mudslide, bottom plate bulging, working face extrusion, and support failure.

[0034] Based on the comprehensive construction risk level, the tunneling advance, excavation step distance, advanced water control parameters, advanced grouting parameters, support parameters, and bottom plate control parameters are dynamically determined to enable timely implementation of measures such as short advance, strong water control, rapid support, and early closure under high-risk conditions, thereby improving the construction safety of underground engineering in high-stress, water-rich soft rock.

[0035] Finally, water hazard indicators and surrounding rock deformation indicators are collected in real time during construction to enable dynamic correction of construction parameters, allowing the construction parameters to be dynamically adjusted according to the water hazard status and the development of surrounding rock deformation.

[0036] This method is applicable to underground engineering construction in high-stress, water-rich soft rock, and can provide dynamic determination basis for parameters such as tunneling advance, excavation step distance, advance water exploration and drainage, advance grouting, support closure, bottom slab closure, and anchor bolt and cable support.

[0037] Multiple water hazard indicators include pre-drilling water pressure, water output per unit time, borehole water attenuation rate, borehole mud-bearing water output status, and grouting pressure variation characteristics. In this embodiment, the pre-drilling water pressure is measured by water pressure sensors arranged in pre-exploration holes, drainage holes, grouting holes, or dedicated pressure measuring holes on the working face; the water output per unit time is measured by flow meters installed in the borehole opening, drainage pipeline, or roadway drainage ditch; the borehole water output attenuation rate is determined based on the change in borehole water output per unit time during continuous monitoring; the borehole mud-bearing water output state is determined based on the turbidity of the water output from the borehole opening, the mud and sand content, mud and sand inrush, borehole collapse, or borehole diameter reduction; the grouting pressure change characteristics include the grouting pressure rise rate, grouting pressure stability value, grouting pressure drop phenomenon, and pressure change corresponding to unit grouting volume, which are measured by grouting pipeline pressure sensors, grouting pump pressure recording devices, or grouting flow monitoring devices, and are used to determine the grout diffusion range, the degree of connectivity of water-rich fissures, and the water-blocking reinforcement effect.

[0038] Multiple deformation indicators include face extrusion, sidewall convergence, roof subsidence, floor bulge, floor bulge rate, and anchor bolt or cable force growth rate. In this embodiment, face extrusion is obtained by measuring with a laser rangefinder, 3D laser scanner, total station, photogrammetry device, or contact displacement gauge; sidewall convergence is obtained by measuring with a roadway cross-section convergence monitoring device, distance sensor, or convergence meter; roof subsidence is obtained by measuring with a roof separation meter, roof displacement gauge, or roadway cross-section scanning device; floor bulge is obtained by measuring with a floor displacement gauge, roof and floor convergence monitoring device, or cross-section scanning device; floor bulge rate is determined based on the difference in floor bulge between adjacent monitoring times and the monitoring time interval; anchor bolt or cable force growth rate is determined based on the difference in anchor bolt or cable force between adjacent monitoring times and the monitoring time interval.

[0039] Dimensionless processing includes two cases.

[0040] For positive indicators where higher values ​​indicate higher risk, the following method is used for dimensionless processing: ; For contrarian indicators where larger values ​​correspond to lower risk, the following method is used for dimensionless processing: ; In the formula, X i Let X be the i-th measured index. i ′ represents the dimensionless index value, all of which are in the range of 0 to 1; X i,min and X i,max These are the minimum and maximum values ​​corresponding to the i-th indicator. In this embodiment, the minimum and maximum values ​​corresponding to the i-th indicator are determined based on engineering design parameters, historical on-site monitoring data, test results, or construction safety control requirements; when the dimensionless result is less than 0, it is taken as 0, and when the dimensionless result is greater than 1, it is taken as 1, so that the values ​​of each indicator are all within the range of 0 to 1.

[0041] Flood Risk Index R w The calculation formula is: ; In the formula, A′ is the pre-drilling water pressure after dimensionless processing; B′ is the water output per unit time after dimensionless processing; η q ′ represents the borehole water attenuation rate after dimensionless processing. A smaller borehole water attenuation rate indicates stronger continuous water-rich fracture recharge and a higher risk of water damage. Therefore, (1-η) is used. q C′ is the water attenuation risk item in the water hazard risk index; C′ is the borehole mud-bearing water state index after dimensionless processing; D′ is the grouting pressure change characteristic index after dimensionless processing; a1, a2, a3, a4, and a5 are the weighting coefficients corresponding to the working face or advanced borehole water pressure, water output per unit time, water attenuation risk item, borehole mud-bearing water state, and grouting pressure change characteristic, respectively, and satisfy: a1+a2+a3+a4+a5=1.

[0042] Deformation Risk Index R d The calculation formula is: ; In the formula, E′ is the extrusion amount of the tunnel face after dimensionless treatment, F′ is the convergence amount of the two sides after dimensionless treatment, G′ is the subsidence amount of the roof after dimensionless treatment, H′ is the bulging amount of the bottom plate after dimensionless treatment, I′ is the bulging rate of the bottom plate after dimensionless treatment, and J′ is the force growth rate of the anchor bolt or anchor cable after dimensionless treatment; b1, b2, b3, b4, b5, and b6 are the weight coefficients of the corresponding indicators, and satisfy: b1+b2+b3+b4+b5+b6=1.

[0043] In this embodiment, the weighting coefficient a i b i It can be determined based on engineering experience, analytic hierarchy process (AHP), entropy weighting method, expert weighting method, historical monitoring data inversion, or construction feedback correction results.

[0044] Comprehensive construction risk index R c The calculation formula is: ; In the formula: R c R is a comprehensive construction risk index. w R is the flood risk index. d It is the deformation risk index; and R w and R d All values ​​are dimensionless indices ranging from 0 to 1. In this embodiment, the comprehensive construction risk index R... c It is used to characterize the combined effect of water hazard risk and surrounding rock deformation risk within the current construction cycle or monitoring period, and serves as the basis for determining the comprehensive construction risk level of the current construction cycle or monitoring period and current or subsequent construction parameters.

[0045] Three risk thresholds are set: a first risk threshold T1, a second risk threshold T2, and a third risk threshold T3, where T1 < T2 < T3.

[0046] When R c When the risk level is less than T1, the current construction cycle or monitoring cycle is determined to be at a low risk level.

[0047] When T1≤R c When the risk level is less than T2, the current construction cycle or monitoring cycle is determined to be at a medium risk level.

[0048] When T2≤R c When the risk level is less than T3, the current construction cycle or monitoring cycle is determined to be at a high risk level.

[0049] When R c When the risk level is ≥T3, the current construction cycle or monitoring cycle is determined to be at an extremely high risk level.

[0050] The overall construction control mode for the current construction cycle or monitoring period is determined based on the comprehensive construction risk level. When the comprehensive construction risk level is low, conventional construction, conventional advance water exploration and drainage, conventional support, and conventional closed-loop control modes are adopted. Among them, conventional construction, conventional advance water exploration and drainage, conventional support, and conventional closed-loop control modes can be selected with appropriate construction parameters according to the usual construction specifications. There are no restrictions on the specific construction parameters here.

[0051] When the overall construction risk level is medium risk, a construction control mode is adopted that shortens the advance advance, strengthens advance water exploration and drainage, advances support closure, and local drainage treatment. In this medium risk mode, compared with the conventional construction mode, the advance advance advance advance advance advance advance advance water exploration and drainage range, length and frequency are appropriately increased, and the support closure and local drainage treatment are faster.

[0052] When the overall construction risk level is high, a construction control mode is adopted, which includes short advance grouting, enhanced pre-grouting or water-blocking grouting, accelerated support closure, early control of the bottom slab, and reinforcement of anchor bolts and cables. In this high-risk mode, compared with the medium-risk mode, the construction advance is shorter, the support closure is faster, and support measures such as pre-grouting or water-blocking grouting, early control of the bottom slab, and reinforcement of anchor bolts and cables are added.

[0053] When the overall construction risk level is extremely high, normal construction is suspended, and measures such as advance water drainage and pressure reduction, face sealing, advance water-blocking grouting, corner locking, temporary slab sealing, or reinforced support are implemented. Construction resumes only after the overall construction risk level has decreased. In the case of extremely high risk, construction is suspended entirely, and reinforced support measures that improve the construction risk level are implemented. Construction resumes only after the overall construction risk level has decreased.

[0054] During construction, if continuous water inrush and mud inrush, face instability, rapid bulging of the base plate, significant damage to the support structure, uncontrolled grouting, or a continuous increase in the deformation rate of the surrounding rock occur, the current construction cycle or monitoring period will be directly classified as an extremely high-risk level, and construction will be suspended, with reinforced support measures implemented. In this embodiment, if one or more of the following abnormal conditions are detected: water inrush, mud inrush, sand inrush, continuous increase in borehole water output, continuous increase in borehole water pressure, increased mud and water output from the borehole, sudden drop in grouting pressure, difficulty in establishing grouting pressure, abnormal increase in unit grouting volume, sudden increase in face extrusion, sudden increase in the convergence rate of the two sides, sudden increase in the roof settlement rate, sudden increase in the bulging rate of the base plate, or sudden increase in the rate of increase in anchor bolt or anchor cable stress, the comprehensive construction risk level of the current construction cycle or monitoring period will be raised by one level, and corresponding risk level handling measures will be implemented.

[0055] If the water hazard risk index decreases while the deformation risk index increases after construction, the pre-control water intensity should be maintained or reduced, and the anchor bolt and cable support density should be increased, the support lag distance shortened, or the bottom plate closed in advance. If the water hazard risk index increases while the deformation risk index decreases, the number of pre-exploration and drainage holes should be increased, the pre-grouting length extended, or the water-blocking grouting intensity increased. If both the water hazard risk index and the deformation risk index increase, normal construction should be suspended and comprehensive reinforcement treatment carried out.

[0056] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for dynamically determining construction parameters for multi-source monitoring of high-stress, water-rich soft rock, characterized in that, The determination method includes the following steps: Step 1: During the construction of underground engineering projects in high-stress, water-rich, soft rock, obtain multiple water hazard indicators and multiple deformation indicators within the current construction cycle or monitoring cycle. Step 2: Dimensionless processing is performed on multiple water hazard indicators. Based on the degree of impact of each water hazard indicator on construction safety, a weighted calculation is performed on the dimensionless water hazard indicators to obtain the water hazard risk index R for the current construction cycle or monitoring period. w ; Step 3: Perform dimensionless processing on multiple deformation indices. Based on the degree of influence of each deformation index on the stability of the surrounding rock and the safety of the support, perform weighted calculation on the dimensionless deformation indices to obtain the deformation risk index R for the current construction cycle or monitoring cycle. d ; Step 4: Establish a comprehensive construction risk index R c The correspondence between risk levels and water hazard risk index R; w and deformation risk index R d Determine the comprehensive construction risk index R for the current construction cycle or monitoring cycle. c To determine the risk level of the current construction cycle or monitoring cycle; Step 5, based on the current comprehensive construction risk index R c Determine the current construction control parameters; Step 6: Carry out the current construction according to the construction parameters determined in Step 5, and continue to collect water hazard indicators and surrounding rock deformation indicators during the construction process. Repeat Steps 1-5 to calculate the comprehensive construction risk index R. c Updates and adjustments will be made to subsequent construction parameters.

2. The method for dynamically determining construction parameters for multi-source monitoring of high-stress, water-rich soft rock according to claim 1, characterized in that, The water hazard indicators include advanced borehole water pressure, water output per unit time, borehole water output attenuation rate, borehole mud-bearing water output status, and grouting pressure variation characteristics.

3. The method for dynamically determining construction parameters for multi-source monitoring of high-stress, water-rich soft rock according to claim 2, characterized in that, The deformation indices include the extrusion amount at the working face, the convergence amount at both sides, the subsidence amount at the top plate, the bulging amount at the bottom plate, the bulging rate at the bottom plate, and the rate of force increase of the anchor bolts or anchor cables.

4. The method for dynamically determining construction parameters for multi-source monitoring of high-stress, water-rich soft rock according to claim 3, characterized in that, The dimensionless processing includes two cases; For positive indicators where higher values ​​indicate higher risk, the following method is used for dimensionless processing: ； For contrarian indicators where larger values ​​correspond to lower risk, the following method is used for dimensionless processing: ； In the formula, X i Let X be the i-th measured index. i ′ represents the dimensionless index value, all of which are in the range of 0 to 1; X i,min and X i,max These are the minimum and maximum values ​​corresponding to the i-th indicator, respectively.

5. The method for dynamically determining construction parameters for multi-source monitoring of high-stress, water-rich soft rock according to claim 3, characterized in that, The water hazard risk index R w The calculation formula is: ； In the formula, A′ is the pre-drilling water pressure after dimensionless processing; B′ is the water output per unit time after dimensionless processing. η q ′ represents the borehole water attenuation rate after dimensionless processing. A smaller borehole water attenuation rate indicates stronger continuous water-rich fracture recharge and a higher risk of water damage. Therefore, (1-η) is used. q C′ is the water attenuation risk item in the water hazard risk index; C′ is the borehole mud-bearing water state index after dimensionless processing; D′ is the grouting pressure change characteristic index after dimensionless processing; a1, a2, a3, a4, and a5 are the weighting coefficients corresponding to the working face or advanced borehole water pressure, water output per unit time, water attenuation risk item, borehole mud-bearing water state, and grouting pressure change characteristic, respectively, and satisfy: a1+a2+a3+a4+a5=1.

6. The method for dynamically determining construction parameters for multi-source monitoring of high-stress, water-rich soft rock according to claim 5, characterized in that, The deformation risk index R d The calculation formula is: ； In the formula, E′ is the extrusion amount of the tunnel face after dimensionless treatment, F′ is the convergence amount of the two sides after dimensionless treatment, G′ is the subsidence amount of the roof after dimensionless treatment, H′ is the bulging amount of the bottom plate after dimensionless treatment, I′ is the bulging rate of the bottom plate after dimensionless treatment, and J′ is the force growth rate of the anchor bolt or anchor cable after dimensionless treatment; b1, b2, b3, b4, b5, and b6 are the weight coefficients of the corresponding indicators, and satisfy: b1+b2+b3+b4+b5+b6=1.

7. The method for dynamically determining construction parameters for multi-source monitoring of high-stress, water-rich soft rock according to claim 6, characterized in that, The comprehensive construction risk index R c The calculation formula is: ； In the formula: R c R is a comprehensive construction risk index. w R is the flood risk index. d It is the deformation risk index; and R w and R d All are dimensionless index values ​​in the range of 0 to 1.

8. The method for dynamically determining construction parameters for multi-source monitoring of high-stress, water-rich soft rock according to claim 7, characterized in that, Three risk thresholds are set: a first risk threshold T1, a second risk threshold T2, and a third risk threshold T3, where T1 < T2 < T3; When R c When the risk level is less than T1, the current construction cycle or monitoring cycle is determined to be low-risk. When T1≤R c When the risk level is less than T2, the current construction cycle or monitoring cycle is determined to be at a medium risk level. When T2≤R c When the risk level is <T3, the current construction cycle or monitoring cycle is determined to be high-risk. When R c When the risk level is ≥T3, the current construction cycle or monitoring cycle is determined to be at an extremely high risk level.

9. The method for dynamically determining construction parameters for multi-source monitoring of high-stress, water-rich soft rock according to claim 8, characterized in that, Determine the overall construction control mode within the current construction cycle or monitoring cycle based on the comprehensive construction risk level; When the overall construction risk level is low, conventional construction, conventional advance water exploration and drainage, conventional support and conventional closed control mode are adopted. When the overall construction risk level is medium risk, a construction control mode is adopted that includes shortening the advance, strengthening advance water exploration and drainage, early support closure, and local drainage treatment. When the overall construction risk level is high, a construction control mode is adopted, which includes short advance, enhanced advanced grouting or water-blocking grouting, accelerated support closure, early control of the bottom plate, and reinforcement of anchor bolts and cables. When the overall construction risk level is extremely high, normal construction shall be suspended and measures such as advance water drainage and pressure reduction, face sealing, advance water blocking grouting, bottom corner locking, temporary sealing of the bottom slab, or reinforcement of support shall be taken. Construction shall be resumed after the overall construction risk is reduced.

10. The method for dynamically determining construction parameters for multi-source monitoring of high-stress, water-rich soft rock according to claim 9, characterized in that, During construction, if there are continuous water and mud inrushes, instability of the working face, rapid bulging of the bottom plate, obvious damage to the support structure, uncontrolled grouting, or a continuous increase in the deformation rate of the surrounding rock, the current construction cycle or monitoring cycle will be directly judged as an extremely high risk level, and construction will be suspended and support measures will be taken.

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