Early warning and handling method for water inrush of deep and long tunnel

Abstract

The invention discloses a deep and long tunnel water inrush early warning and disposal method, and relates to the technical field of deep and long tunnel water inrush construction.The deep and long tunnel water inrush early warning and disposal method comprises the steps that infrared water detection equipment is arranged on the tunnel face and the side wall of a tunnel, infrared reflection signals are transmitted and received, and the position, the water content and the flow direction of underground water are recognized; generating underground water distribution data; the data is compared with a preset risk threshold value, when the underground water pressure is larger than or equal to 1.5 MPa or the water content is larger than or equal to 30%, it is judged that the area is a high-risk area, and the area is marked with a red flickering icon in a three-dimensional visual interface; a drainage hole is drilled in the high-risk area, a PVC drainage pipe with a filter screen is arranged in the drainage hole, and underground water is drained to the water collecting well; then a concrete reinforcing layer is sprayed around the drainage holes; and monitoring the pressure of the underground water after drainage in real time, and if the pressure is not reduced to 1.0 MPa or below, densifying the drainage hole and thickening the reinforcing layer to realize accurate early warning and rapid disposal of the water inrush risk.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of deep long tunnel water inrush construction, in particular to a deep long tunnel water inrush early warning and disposal method. BACKGROUND

[0002] With the rapid development of infrastructure construction, deep long tunnel projects are increasingly widely used in mountainous areas of transportation, water conservancy and hydropower, etc. In the process of tunnel construction, the detection and control of groundwater have always been the key technical link to ensure construction safety. The traditional groundwater detection method has gone through the development path from physical drilling to geological radar, and then to infrared detection technology, with continuously improved detection accuracy and efficiency. At the same time, the tunnel water inrush early warning technology has gradually developed from single manual patrol to intelligent monitoring system integrating multiple sensors, providing an important guarantee for tunnel construction safety.

[0003] However, the existing technology still has obvious deficiencies in practical application: first, the comparison and determination standard of infrared detection data and risk threshold is not accurate enough, which is easy to miss or misjudge; second, the parameters of drainage hole arrangement (such as hole diameter, hole depth, spacing) lack systematic quantitative standards, resulting in unstable drainage effect; third, the proportioning and spraying process of the concrete reinforcement layer cannot dynamically match the actual groundwater pressure change, making it difficult to guarantee the reinforcement effect; fourth, there is a lack of continuous monitoring and emergency response mechanism for pressure change after drainage, which cannot take remedial measures in time when the initial disposal effect is not good. These problems restrict the reliability and practicality of deep long tunnel water inrush early warning and disposal technology. SUMMARY

[0004] The main purpose of the present application is to provide a deep long tunnel water inrush early warning and disposal method, which aims to dispose the water inrush risk of deep long tunnel and improve construction safety.

[0005] To achieve the above purpose, the deep long tunnel water inrush early warning and disposal method provided by the present application comprises: Infrared water detection equipment is arranged at the tunnel face and side wall, infrared beams are emitted and reflected signals are received by using the infrared water detection equipment, the existence position, water content and flow direction of groundwater are identified according to the signal intensity and frequency difference, and groundwater distribution data is formed; The groundwater distribution data is compared with the preset water inrush risk threshold, if the groundwater pressure of any region is ≥1.5MPa or the water content is ≥30% volume ratio, it is determined as a high risk area; The high risk area position is marked through a three-dimensional visualization interface, and a red flashing icon and pressure value are superimposed and displayed; Drainage holes are drilled in the high-risk area, and PVC drainage pipes with filters are installed in the drainage holes to divert groundwater to a collection well; wherein the diameter of the drainage holes is 50mm to 80mm, and the depth of the drainage holes is 1.2 to 1.5 times the diameter of the tunnel. A reinforced concrete layer is sprayed around the drainage hole; wherein the concrete is mixed in the following proportions by mass: cement: sand: aggregate: quick-setting agent = 1:2:3:0.05, and the thickness of the reinforced concrete layer is ≥10cm. Real-time monitoring of groundwater pressure changes after drainage; if the groundwater pressure does not drop below 1.0 MPa, the density of the drainage holes is increased to 2 to 3 per square meter, and the concrete reinforcement layer is sprayed to a thickness of ≥15 cm.

[0006] In one embodiment, the step of arranging infrared water detection equipment at the tunnel face and sidewalls, using the infrared water detection equipment to emit infrared beams and receive reflected signals, and identifying the location, water content, and flow direction of groundwater based on differences in signal strength and frequency to form groundwater distribution data includes: An infrared water detection device is arranged every 5m along the longitudinal direction of the tunnel. Each set of infrared water detection devices includes one device at the center of the tunnel face and one device on each of the two side walls. The infrared water detection device emits infrared pulse signals at a frequency of 10kHz to 15kHz and collects the reflected signals every 30 seconds. The collected reflection signals are filtered to remove reflection noise from the rock interface, and the signals in the frequency range of 8kHz to 12kHz are retained for groundwater identification. When the water content is ≥25% in three consecutive samples from the same location, a data anomaly marker is triggered.

[0007] In one embodiment, the drilling angle of the drainage hole is perpendicular to the tunnel wall by ±10°, and the hole spacing is 1 / 10 to 1 / 5 of the length of the high-risk area.

[0008] In one embodiment, the inner diameter of the PVC drainage pipe is 30mm to 50mm, and the outer wall of the PVC drainage pipe is wrapped with permeable geotextile to filter mud and sand with a particle size ≤0.5mm.

[0009] In one embodiment, the permeable geotextile comprises 90% polypropylene fiber and 10% carbon fiber by weight.

[0010] In one embodiment, after drilling drainage holes in the high-risk area, installing PVC drainage pipes with filters inside the drainage holes, and diverting groundwater to a collection well, the method for early warning and handling of water inrush in deep and long tunnels further includes: A pressure sensor is installed at the outlet of the drain hole to monitor the drainage flow rate in real time. If the drainage flow rate is ≥5L / min for 10 minutes, the standby drain pump will be automatically started. The power of the drain pump is calculated to be 1.5kW for every 100L / min flow rate.

[0011] In one embodiment, the step of spraying a concrete reinforcement layer around the drainage hole includes: Before spraying the concrete reinforcement layer, fiberglass anchors with a length of 1.5m to 2m are inserted at a spacing of 0.5m*0.5m to form a reinforcement zone; wherein, the fiberglass anchors comprise 60% epoxy resin matrix and 40% fiberglass by weight.

[0012] In one embodiment, the method for early warning and handling of water inrush in deep and long tunnels further includes: real-time monitoring of groundwater pressure changes after drainage; if the groundwater pressure does not drop below 1.0 MPa, increasing the density of drainage holes to 2-3 per square meter; and supplementing the process by spraying the concrete reinforcement layer to a thickness ≥15 cm. Distributed fiber optic sensors are used to monitor the strain of the concrete layer. If the strain value is ≥200με, a reinforcement alarm for the reinforcement layer is triggered. During reinforcement, additional concrete with sprayed accelerator added to areas with excessive strain is added to increase the amount of concrete to 0.07 parts by weight, and the anchor rods are densified to a spacing of 0.3m*0.3m.

[0013] In one embodiment, before the step of arranging infrared water detection equipment at the tunnel face and sidewalls, using the infrared water detection equipment to emit infrared beams and receive reflected signals, and identifying the location, water content, and flow direction of groundwater based on differences in signal strength and frequency to form groundwater distribution data, the method for early warning and handling of water inrush in deep and long tunnels further includes: Gravity-based seepage monitors were installed on the tunnel arch. When the burial depth of the gravity-type seepage monitor is ≤50m, the preset water inrush risk threshold is 3L / (m²). 2 h); When the burial depth of the gravity-type seepage monitor is greater than 50m, the preset water inrush risk threshold decreases by 0.5L / (m) for every 10m increase in burial depth. 2 h) Calculation.

[0014] In one embodiment, the step of marking high-risk areas using a 3D visualization interface and displaying them with flashing red icons and pressure values ​​overlaid includes: The collected data on the location, water content, and flow direction of the groundwater are converted into GIS-compatible GeoJSON format and mapped to the tunnel's three-dimensional coordinate system. A BIM model is created based on CAD format drawings of tunnel design, and a hybrid 3D model is generated by overlaying groundwater data. In the three-dimensional model, pressure values ​​are represented by a gradient from red to blue; where red represents a pressure value ≥1.5MPa and blue represents a pressure value ≤0.5MPa. The direction of water flow is represented by dynamic arrows, and the length of the arrows is proportional to the flow velocity.

[0015] The technical solution of this invention establishes a high-risk area determination standard based on a clear numerical threshold (groundwater pressure ≥ 1.5 MPa or water content ≥ 30% by volume) by deploying infrared water detection equipment on the tunnel face and sidewalls and using the difference in signal strength and frequency to identify groundwater distribution data. This effectively solves the problem of missed or false judgments caused by inaccurate determination standards in existing technologies. Furthermore, the invention uses a three-dimensional visualization interface to mark the location of high-risk areas with flashing red icons and pressure values, transforming abstract detection data into intuitive visual information and avoiding the problems of information delays and misunderstandings in traditional manual inspections. Simultaneously, by specifying the drainage hole diameter as 50mm–80mm and the hole depth as 1.2–1.5 times the tunnel diameter, and combining this with a PVC drainage pipe with a filter, the invention overcomes the problem of drainage effect caused by the lack of quantitative standards in the layout of drainage holes in existing technologies. The technology addresses the instability inherent in existing technologies. Furthermore, it employs a precise mix ratio of cement, sand, aggregate, and accelerator (1:2:3:0.05) and controls the sprayed concrete reinforcement layer to a thickness ≥10cm. This solves the problem of insufficient dynamic matching between the reinforcement layer mix ratio and groundwater pressure changes in current technologies. More importantly, by real-time monitoring of groundwater pressure changes after drainage, and automatically triggering an emergency response mechanism to increase the density of drainage holes to 2-3 per square meter and supplement the sprayed concrete reinforcement layer to a thickness ≥15cm when the pressure has not dropped below 1.0MPa, a dynamic closed-loop system of pressure feedback and treatment adjustment has been established. This compensates for the shortcomings of existing technologies, such as the lack of continuous monitoring and emergency response mechanisms, and the inability to promptly remedy unsatisfactory initial treatment results. This fundamentally improves the systematicness, accuracy, and practicality of early warning and treatment technologies for water inrush in deep and long tunnels, providing a more reliable technical guarantee for tunnel construction safety. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0017] Figure 1 This is a flowchart illustrating an embodiment of the method for early warning and handling of water inrush in deep and long tunnels provided by the present invention.

[0018] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0020] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0021] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0022] With the rapid development of infrastructure construction, deep and long tunnel engineering is increasingly widely used in mountainous transportation, water conservancy and hydropower, and other fields. During tunnel construction, groundwater detection and control has always been a key technical aspect ensuring construction safety. Traditional groundwater detection methods have evolved from physical drilling to ground-penetrating radar, and then to infrared detection technology, with continuously improving detection accuracy and efficiency. Simultaneously, tunnel water inrush early warning technology has also gradually developed from simple manual inspections to intelligent monitoring systems integrating multiple sensors, providing crucial protection for tunnel construction safety.

[0023] However, existing technologies still have significant shortcomings in practical applications: First, the comparison criteria between infrared detection data and risk thresholds are not precise enough, easily leading to missed or false alarms; second, the parameters for drainage hole layout (such as hole diameter, depth, and spacing) lack systematic quantitative standards, resulting in unstable drainage effects; third, the mix proportions and spraying processes of the concrete reinforcement layer fail to dynamically match actual groundwater pressure changes, making it difficult to guarantee the reinforcement effect; and fourth, there is a lack of continuous monitoring and emergency response mechanisms for pressure changes after drainage, making it impossible to take timely remedial measures when the initial treatment is ineffective. These problems restrict the reliability and practicality of early warning and treatment technologies for water inrush in deep and long tunnels.

[0024] To address this technical problem, this invention proposes a method for early warning and handling of water inrush in deep and long tunnels.

[0025] Please see Figure 1 In one embodiment of the present invention, the method for early warning and handling of water inrush in deep and long tunnels includes: S10, infrared water detection equipment is installed on the tunnel face and sidewalls. The infrared water detection equipment emits infrared beams and receives reflected signals. The location, water content and flow direction of groundwater are identified based on the difference in signal strength and frequency, thus forming groundwater distribution data. S20, compare the groundwater distribution data with the preset water inrush risk threshold. If any area is found to have a groundwater pressure ≥1.5MPa or a water content ≥30% of the volume, it is determined to be a high-risk area. S30 uses a 3D visualization interface to mark the location of high-risk areas, which are displayed with flashing red icons and pressure values ​​overlaid. S40, Drainage holes are drilled in the high-risk area, and PVC drainage pipes with filters are installed in the drainage holes to divert groundwater to a collection well; wherein, the diameter of the drainage holes is 50mm to 80mm, and the depth of the drainage holes is 1.2 to 1.5 times the diameter of the tunnel. S50, spray a concrete reinforcement layer around the drainage hole; wherein the concrete is mixed in the following proportions by mass: cement: sand: aggregate: quick-setting agent = 1:2:3:0.05, and the spray thickness of the concrete reinforcement layer is ≥10cm. S60, monitor the change in groundwater pressure after drainage in real time. If the groundwater pressure does not drop below 1.0 MPa, increase the density of the drainage holes to 2 to 3 per square meter, and supplement the concrete reinforcement layer to a thickness of ≥15 cm.

[0026] In practical applications, infrared water detection equipment can be understood as a detection device based on the principle of infrared reflection. Its main function is to obtain groundwater information by analyzing the differences in the infrared reflection characteristics of different media. For example, it can adapt to different geological conditions by adjusting the infrared emission frequency and receiving sensitivity, or it can use a multi-band infrared combination detection method to improve signal discrimination ability, thereby achieving accurate identification of the location, water content, and flow direction of groundwater.

[0027] Furthermore, the preset water inrush risk threshold can be understood as a set of reference standards for judging the level of water inrush risk, and its setting is based on engineering measured data and empirical statistics. For example, the threshold range can be dynamically adjusted by simulating the variation law of groundwater pressure and water content under different geological conditions, or a risk assessment model for different regions can be established by combining historical construction data, thereby ensuring the objectivity and accuracy of the judgment results.

[0028] Specifically, a 3D visualization interface can be understood as a technical means of transforming abstract data into intuitive graphics. Its core lies in presenting key information through a combination of colors, icons, and numerical values. For example, a heat map can be used to display the distribution of groundwater pressure, or the length and direction of dynamic arrows can be used to represent the speed and direction of water flow, thereby helping construction personnel quickly grasp the status of risk areas.

[0029] Furthermore, the design parameters of drainage holes, such as the selection of hole diameter and depth, need to comprehensively consider the characteristics of the tunnel structure and the flow characteristics of groundwater. For example, the relationship between water flow rate and surrounding rock stability under different hole diameters can be tested experimentally, or the hole depth ratio can be optimized according to the tunnel diameter and surrounding rock type, thereby ensuring the stability and safety of drainage effect.

[0030] The mix design of reinforced concrete layers requires balancing factors such as material strength, workability, and setting time. For example, the initial setting time of concrete can be controlled by adjusting the amount of accelerator added, or a combination of aggregates with different particle sizes can be used to improve the compactness of the concrete, thereby meeting the actual construction requirements.

[0031] The innovation of this application lies in its integration of a full-process mechanism encompassing detection, assessment, early warning, handling, and dynamic response, which systematically improves the accuracy and reliability of water inrush risk management. Compared to existing technologies, which suffer from imprecise assessment criteria, lack of quantitative standards for drainage hole layout, and insufficient matching between reinforcement layers and groundwater pressure changes, this application effectively solves these technical challenges through clearly defined numerical thresholds, scientific parameter design, and a dynamic feedback mechanism. This provides more reliable technical support for water inrush early warning and handling in deep and long tunnel construction.

[0032] The working principle of this embodiment is as follows: Infrared water detection equipment is deployed at the tunnel face and sidewalls. By emitting infrared beams and receiving reflected signals, and utilizing the differences in the infrared reflection characteristics of different media, the location, water content, and flow direction of groundwater are identified, thereby generating groundwater distribution data. This process effectively avoids the inaccurate judgment problem caused by noise interference in traditional methods, providing a reliable data foundation for subsequent risk assessment. Furthermore, the generated groundwater distribution data is compared with a preset water inrush risk threshold. If any area is found to have a groundwater pressure ≥1.5MPa or a water content ≥30% by volume, it is determined to be a high-risk area. This judgment mechanism sets specific numerical thresholds based on engineering measured data, ensuring that risk identification is neither overly conservative nor overly simplistic, significantly improving the scientific nature and operability of the judgment criteria.

[0033] After identifying high-risk areas, their locations are marked using a 3D visualization interface, displayed with a flashing red icon and pressure values ​​superimposed. This dual-indication mechanism intuitively conveys early warning information, enabling construction personnel to quickly locate high-risk areas and understand pressure status, thereby enhancing decision support capabilities. Subsequently, drainage holes are drilled in the high-risk areas, with PVC diversion pipes equipped with filters installed inside, diverting groundwater to a collection well. The diameter of the drainage holes is limited to 50mm–80mm, and the hole depth is 1.2–1.5 times the tunnel diameter. This design not only ensures the unobstructed flow of water and structural stability but also optimizes drainage coverage. Furthermore, the filter design effectively intercepts sediment, preventing pipe blockage and ensuring the stability and sustainability of the drainage treatment.

[0034] Simultaneously, a reinforced concrete layer was sprayed around the drainage holes. The concrete mix ratio by weight was cement:sand:aggregate:accelerator = 1:2:3:0.05, with a spray thickness ≥10cm. This mix ratio balanced the concrete's strength, workability, and setting speed. The precise addition of the accelerator ensured rapid formation of the supporting structure, while the required thickness provided sufficient compressive strength, effectively suppressing surrounding rock deformation and resolving the issue of insufficient dynamic matching between the reinforced layer and groundwater pressure. Groundwater pressure changes were monitored in real time after drainage. If the pressure did not drop below 1.0MPa, the density of drainage holes was increased to 2-3 per square meter, and a reinforced concrete layer was added to a thickness ≥15cm. This established a closed-loop mechanism for pressure feedback and treatment adjustment, dynamically optimizing drainage density and reinforcement strength based on actual pressure changes. This avoided the rigidity of fixed-parameter treatment and ensured timely reinforcement when the initial treatment did not meet expectations, fundamentally improving the continuous monitoring and emergency response system.

[0035] In an embodiment of the present invention, the step of arranging infrared water detection equipment at the tunnel face and sidewalls, using the infrared water detection equipment to emit infrared beams and receive reflected signals, and identifying the location, water content, and flow direction of groundwater based on differences in signal strength and frequency to form groundwater distribution data includes: S11, a set of infrared water detection equipment is arranged every 5m along the longitudinal direction of the tunnel. Each set of infrared water detection equipment includes one unit at the center of the tunnel face and one unit on each of the two side walls. S12, the infrared water detection device emits infrared pulse signals with a frequency of 10kHz~15kHz, and collects the reflected signal once every 30 seconds; S13, the collected reflection signal is filtered to remove the reflection noise from the rock interface and retain the signal in the frequency range of 8kHz~12kHz for groundwater identification. S14. When the water content is ≥25% in three consecutive samples from the same location, a data anomaly marker is triggered.

[0036] Specifically, infrared water detection equipment refers to a device that detects groundwater by emitting infrared beams of a specific frequency and receiving the reflected signals. It can employ sensors based on photodiode arrays or detectors based on the pyroelectric effect. The emission of infrared pulse signals at a frequency of 10kHz to 15kHz ensures the signal can effectively penetrate rock strata and has high resolution, aiming to improve detection accuracy and dynamic response capabilities. Filtering refers to the process of removing interference signals using digital signal processing techniques, which can be implemented through bandpass filters or wavelet transform algorithms. The aim is to improve the signal-to-noise ratio and enhance the identification of groundwater characteristics. Data anomaly labeling refers to the operation of marking collected data when specific conditions are met. This can be implemented through setting threshold judgment logic or statistical analysis methods, aiming to reduce false alarm rates and improve the reliability of risk area identification.

[0037] In detail, the above scheme optimizes the layout of infrared water detection equipment, placing one set of equipment every 5 meters along the tunnel's longitudinal direction, and one set at the center of the tunnel face and on each of the two side walls. This achieves comprehensive coverage of key areas of the tunnel, avoiding blind spots. Simultaneously, by setting the infrared pulse signal transmission frequency to 10kHz~15kHz and periodically collecting reflected signals at 30-second intervals, the scheme ensures signal penetration and real-time performance, enabling timely detection of groundwater changes. Furthermore, by filtering the collected reflected signals to remove noise from rock interface reflections and retaining effective signals of 8kHz~12kHz, the signal-to-noise ratio is significantly improved, enhancing the accuracy of groundwater feature identification. Finally, when three consecutive data collections at the same location show a water content ≥25%, a data anomaly marker is triggered. This continuous detection mechanism effectively reduces the possibility of false alarms from single anomalies, ensuring the reliability and stability of anomaly event determination.

[0038] The above technical solution solves the problem of missed or false detections caused by insufficient data collection accuracy when deploying infrared water detection equipment at the tunnel face and sidewalls, and significantly improves the accuracy and reliability of groundwater detection.

[0039] In an embodiment of the present invention, the drilling angle of the drainage hole is perpendicular to the tunnel wall by ±10°, and the hole spacing is 1 / 10 to 1 / 5 of the length of the high-risk area.

[0040] The drilling angle refers to the range of angular deviation between the axis of the drainage hole and the normal to the tunnel wall. It can be precisely controlled using a laser guide in conjunction with an angle sensor to ensure the drilling direction is essentially perpendicular to the tunnel wall, preventing excessive angular deviation that could lead to poor drainage or damage to the hole wall structure. The hole spacing is the distance between the center points of adjacent drainage holes. It can be determined by measuring and marking based on the actual length of the high-risk area, ensuring uniform and comprehensive drainage hole distribution and avoiding insufficient drainage or resource waste due to improper spacing.

[0041] Specifically, the above-mentioned solution optimizes the layout of drainage holes by limiting specific parameters for drilling angle and hole spacing, thus solving the problem of unstable drainage effect caused by missing parameters in existing technologies. The drilling angle is limited to ±10° perpendicular to the tunnel wall. This range ensures that the drainage holes can effectively guide groundwater outflow while avoiding potential damage to the hole wall structure caused by excessive angles. The hole spacing is set to 1 / 10 to 1 / 5 of the length of the high-risk zone. This dynamic adjustment method allows for the reasonable distribution of drainage holes according to the size of the risk zone, ensuring drainage effect while improving construction efficiency. In addition, the above parameter settings, combined with groundwater distribution data generated by infrared water detection equipment, can more accurately locate high-risk areas, thereby improving the reliability and practicality of the overall water inrush early warning and response system.

[0042] In an embodiment of the present invention, the inner diameter of the PVC drainage pipe is 30mm to 50mm, and the outer wall of the PVC drainage pipe is wrapped with permeable geotextile to filter mud and sand with a particle size ≤0.5mm.

[0043] Specifically, PVC drainage pipes refer to a pipe structure used to guide the flow of groundwater. They can be made of rigid polyvinyl chloride (PVC) material, which has good corrosion resistance and mechanical strength. The inner diameter is set in the range of 30mm to 50mm to ensure sufficient water flow while avoiding efficiency problems caused by excessively large or small sizes. Permeable geotextile is a woven fabric material with filtering functions. It can be made of polypropylene or polyester fibers and its main function is to intercept sediment particles, preventing them from entering the drainage pipe and causing blockages.

[0044] In detail, the above-mentioned solution effectively solves the problem of sediment blockage by limiting the specific structure and filtration mechanism of the PVC drainage pipe, thereby improving the reliability and stability of the drainage system. The defined inner diameter range ensures that the drainage pipe can accommodate sufficient water flow while maintaining a high flow velocity, preventing sediment accumulation due to excessively low flow rates. The introduction of permeable geotextile provides a physical filtration layer, enabling precise control of the filtration level and intercepting sediment particles with a diameter not exceeding 0.5mm, thus maintaining the smoothness of the drainage process. Furthermore, this solution, combined with the drainage hole layout in the aforementioned high-risk areas and subsequent concrete reinforcement technology, forms a complete water inrush response system, significantly improving the overall effectiveness of groundwater management during tunnel construction.

[0045] The above technical solutions not only solved the problem of easy blockage in the diversion pipes, but also achieved efficient and stable groundwater diversion through reasonable parameter design and material selection, providing an important guarantee for the safety of deep and long tunnel construction.

[0046] In an embodiment of the present invention, the permeable geotextile comprises 90% polypropylene fiber and 10% carbon fiber by weight.

[0047] Specifically, permeable geotextile refers to a composite material used for filtering sediment, which can be achieved by using different proportions of fiber combinations. Among them, polypropylene fibers provide good permeability and filtration capacity, ensuring that sediment particles with a diameter ≤0.5mm are effectively intercepted; at the same time, the addition of 10% carbon fiber enhances the mechanical strength and corrosion resistance of the geotextile, making it less prone to damage in high-pressure drainage environments and extending its service life.

[0048] In detail, the above solution addresses the issues of incomplete filtration of sediment and easy material damage by optimizing the composition ratio of the permeable geotextile. The specific combination of polypropylene fiber and carbon fiber ensures both filtration efficiency and improved material durability. In practical applications, wrapping this permeable geotextile around the outer wall of the PVC drainage pipe effectively filters sediment, preventing drainage system malfunctions caused by insufficient filtration or material failure. Furthermore, this material combination can adapt to complex underground environments and maintain stable performance during long-term use, thereby enhancing the reliability of the entire drainage system.

[0049] In an embodiment of the present invention, after drilling drainage holes in the high-risk area, installing PVC drainage pipes with filters in the drainage holes, and diverting groundwater to a collection well, the method for early warning and handling of water inrush in deep and long tunnels further includes: S401, a pressure sensor is installed at the outlet of the drain hole to monitor the drainage flow rate in real time. If the drainage flow rate is ≥5L / min for 10 minutes, the standby drain pump will be automatically started. The power of the drain pump is calculated to be 1.5kW for every 100L / min flow rate.

[0050] Specifically, a pressure sensor is a device that can detect fluid pressure and convert it into a measurable signal. It can be implemented using pressure sensing elements based on different principles, such as piezoresistive, capacitive, or strain gauge types. In practical applications, the pressure sensor must be installed in close proximity to the drain outlet to accurately collect real-time flow data from the drainage point. Drainage flow rate refers to the volume of groundwater passing through the drain outlet per unit time, which can be calculated using the pressure value detected by the pressure sensor and fluid mechanics formulas. Automatic start-up refers to the process by which the system automatically triggers equipment operation based on preset conditions. This can be achieved through a programmable logic controller (PLC) or a microcontroller control system, aiming to reduce manual intervention and improve emergency response speed.

[0051] In detail, in the above scheme, a pressure sensor, as a key component, is placed at the drain outlet to collect real-time drainage flow data. When the drainage flow rate reaches or exceeds 5 L / min and lasts for 10 minutes, the system determines it to be in an abnormal state and triggers the start-up mechanism of the backup drainage pump. This judgment logic effectively avoids false start-ups caused by short-term flow fluctuations by setting both a flow rate threshold and a duration condition. The power configuration of the backup drainage pump is precisely matched according to the drainage flow rate, based on a calculation rule of 1.5 kW for every 100 L / min flow rate, ensuring that the pump performance is adapted to actual needs. This design not only optimizes drainage efficiency but also avoids energy waste.

[0052] Building upon this foundation, the aforementioned solution significantly improves the timeliness and reliability of water inrush early warning and response by introducing real-time monitoring and automatic control mechanisms. The placement of pressure sensors allows for continuous tracking of drainage flow data, while the automatic activation mechanism provides emergency response capabilities without manual intervention. Especially in cases of poor initial drainage or excessive flow, the rapid intervention of backup drainage pumps effectively reduces the risk of water inrush, thus compensating for the lack of emergency response mechanisms in existing technologies. Furthermore, this solution, combined with the aforementioned infrared water detection equipment, drainage hole layout, and concrete reinforcement layers, forms a more comprehensive water inrush early warning and response system, further enhancing the safety of tunnel construction.

[0053] In an embodiment of the present invention, the step of spraying a concrete reinforcement layer around the drainage hole includes: S51, before spraying the concrete reinforcement layer, fiberglass anchors with a length of 1.5m to 2m are inserted at a spacing of 0.5m*0.5m to form a reinforcement zone; wherein, the fiberglass anchors comprise 60% epoxy resin matrix and 40% fiberglass by weight.

[0054] Specifically, fiberglass anchors are composite anchors made of epoxy resin matrix and fiberglass. They can be prepared using different proportions of epoxy resin and fiberglass to improve the anchor's strength and corrosion resistance. In practical applications, the amount of accelerator added refers to the proportion of accelerator added to the concrete. This can be achieved by adjusting the type and dosage of the accelerator to control the concrete's setting speed and thus quickly form a protective layer. Anchoring agent refers to the material used to fix the anchor. It can be a mixture of various components, such as a combination of silicate cement, expanding agent, and water-reducing agent, to ensure the anchor's firmness and stability.

[0055] In detail, during the process of shotcreting the reinforcement layer around the drainage holes, a reinforcement zone is first formed by inserting fiberglass anchors. These anchors not only provide additional support but also significantly enhance the overall performance of the reinforcement zone through their high strength and corrosion resistance. Subsequently, an initial layer of concrete is shotcreted into the reinforcement zone, with a quick-setting agent added at a rate of 0.08 parts by weight, enabling rapid formation of a protective layer to prevent groundwater erosion. The remaining thickness is shotcreted after 24 hours, allowing the concrete to fully cure and avoiding structural defects that might result from a single-stage shotcrete application. Furthermore, the installation process of the fiberglass anchors includes precise drilling diameter, injection of a specific type of anchoring agent, and grouting under high pressure to ensure anchoring strength. The exposed ends of the anchors are welded to the reinforcing mesh to further integrate the reinforcement structure and prevent displacement. These steps work together to form a stable and durable reinforcement layer that effectively copes with changes in groundwater pressure, solving the problem of easy failure of reinforcement layers caused by the lack of systematic anchor support and staged shotcreting processes in existing technologies.

[0056] The above technical solutions significantly improve the overall stability and compressive strength of the reinforcement layer, providing an important guarantee for tunnel construction safety.

[0057] In an embodiment of the present invention, after real-time monitoring of groundwater pressure changes after drainage, if the groundwater pressure does not drop below 1.0 MPa, the density of the drainage holes is increased to 2 to 3 per square meter, and the concrete reinforcement layer is sprayed to a thickness ≥15 cm. Following this step, the method for early warning and handling of water inrush in deep and long tunnels further includes: S601 uses distributed fiber optic sensors to monitor the strain of the concrete layer. If the strain value is ≥200με, a reinforcement layer strengthening alarm is triggered. For S602, during reinforcement, additional concrete with sprayed accelerator added to areas with excessive strain is added to increase the amount of concrete to 0.07 parts by weight, and the anchor rods are densified to a spacing of 0.3m*0.3m.

[0058] Among them, distributed fiber optic sensors refer to fiber optic sensing devices capable of continuously monitoring structural strain. These sensors can be implemented using fiber optic sensors based on Brillouin scattering or Raman scattering principles, aiming to acquire real-time strain data of the concrete layer and promptly detect potential deformation risks. Concrete with an increased accelerator content of 0.07 parts by mass refers to specially proportioned concrete where the accelerator ratio is increased to accelerate concrete setting. This can be achieved by adjusting the type and dosage of the accelerator, aiming to rapidly enhance the strength of the reinforced layer and meet emergency reinforcement needs. Anchor bolt spacing reduced to 0.3m x 0.3m refers to a technical measure that provides stronger support by reducing the spacing between anchor bolts. This can be achieved by optimizing the anchor bolt arrangement, aiming to effectively suppress concrete layer deformation.

[0059] Specifically, the above technical solution addresses the issue of excessive strain in the concrete layer after supplementary treatment by introducing strain monitoring and dynamic reinforcement mechanisms. First, distributed fiber optic sensors are deployed within the reinforced concrete layer to continuously and in real-time acquire strain data. When the monitored strain value reaches or exceeds 200 με, the system automatically triggers a reinforcement alarm, indicating the need for reinforcement operations. Subsequently, in areas with excessive strain, the construction team adds 0.07 parts by weight of sprayed accelerator to the concrete to rapidly enhance the strength of the reinforcement layer. Simultaneously, by increasing the spacing of the anchor bolts to 0.3m x 0.3m, stronger support is provided, effectively suppressing deformation of the concrete layer. This series of measures ensures the stability and safety of the reinforcement layer under high-pressure conditions.

[0060] Furthermore, the above-mentioned solution, combined with the aforementioned techniques of increasing the density of drainage holes and supplementing the thickness of the concrete reinforcement layer through spraying, forms a more comprehensive risk control system. By monitoring strain changes in real time and implementing targeted reinforcement, not only is the reliability of the reinforcement layer improved, but the overall safety of the treatment plan is also significantly enhanced.

[0061] In an embodiment of the present invention, before the step of arranging infrared water detection equipment at the tunnel face and sidewalls, using the infrared water detection equipment to emit infrared beams and receive reflected signals, and identifying the location, water content, and flow direction of groundwater based on differences in signal strength and frequency to form groundwater distribution data, the method for early warning and handling of water inrush in deep and long tunnels further includes: P10, a gravity-type seepage monitor is installed on the tunnel arch; P20, when the burial depth of the gravity-type seepage monitor is ≤50m, the preset water inrush risk threshold is 3L / (m²). 2 h); P30, when the burial depth of the gravity-type seepage monitor is >50m, the preset water inrush risk threshold is reduced by 0.5L / (m) for every 10m increase in burial depth. 2 h) Calculation.

[0062] Specifically, a gravity-based seepage monitor is a device that assesses groundwater activity by measuring seepage flow rate. It can be implemented using a flowmeter-based sensor or a pressure-sensitive seepage monitoring device. Its purpose is to provide additional environmental parameters, compensating for the limitations of relying solely on infrared detection and providing a more comprehensive basis for risk assessment. The preset inrush risk threshold refers to a risk assessment standard that is dynamically adjusted according to different burial depths. It can be optimized based on geological conditions and construction experience to ensure the accuracy of the assessment results.

[0063] In detail, after deploying gravity-based seepage monitors in the tunnel arch, these monitors can capture seepage data in real time, using this data as a crucial basis for risk assessment. For shallower burial depths, a fixed threshold establishes a benchmark reference value, ensuring the stability of risk assessment under low-pressure environments. For deeper burial depths, a dynamic threshold adjustment method considers the geological characteristics of increased groundwater pressure at deeper depths, allowing the threshold to adapt to different depth conditions and avoiding misjudgments or omissions due to changes in burial depth. This depth-based dynamic adjustment mechanism, combined with detection data from infrared water detection equipment, significantly improves the accuracy and reliability of risk assessment.

[0064] Furthermore, the aforementioned solution addresses the inaccuracy of risk assessment in existing technologies by introducing a gravity-based seepage monitor and a dynamically adjusted threshold. First, the seepage data provided by the gravity-based seepage monitor complements the detection data from the infrared water detection equipment, thus constructing a more comprehensive risk assessment system. Second, the design based on dynamically adjusted thresholds at burial depth fully considers changes in geological characteristics and the construction environment, making the assessment criteria more scientific and reasonable. Overall, this combined approach not only improves the accuracy of risk assessment but also enhances the practicality and reliability of early warning and response technologies for water inrush in deep and long tunnels.

[0065] In an embodiment of the present invention, the step of marking high-risk areas using a three-dimensional visualization interface and displaying them with flashing red icons and pressure values ​​overlaid includes: S61, the collected data on the location of groundwater, water content and flow direction are converted into GIS-compatible GeoJSON format and mapped to the tunnel's three-dimensional coordinate system; S62, Based on the CAD format drawings of the tunnel design, a BIM model is created, and groundwater data is overlaid to generate a hybrid 3D model; S63, in the three-dimensional model, the pressure value is represented by a gradient color from red to blue; wherein, red represents a pressure value ≥1.5MPa, blue represents a pressure value ≤0.5MPa, the direction of water flow is represented by a dynamic arrow, and the length of the arrow is proportional to the flow velocity.

[0066] Specifically, the location of groundwater refers to the specific distribution area of ​​groundwater detected by infrared water detection equipment, which can be achieved using a gridded partitioning method. Water content refers to the proportion of groundwater per unit volume, which can be quantified using signal strength analysis algorithms. Water flow direction refers to the movement trend of groundwater, which can be determined using vector field analysis methods. The purpose of introducing these parameters is to ensure the comprehensiveness and accuracy of the detection data, thereby providing reliable basic data for subsequent 3D visualization.

[0067] In practical applications, data standardization refers to the process of normalizing raw pressure values ​​to eliminate the influence of different dimensions, facilitating unified comparison and visualization. Dynamic updating refers to the operation of periodically synchronizing infrared water detection equipment data and refreshing the 3D model to ensure that the visualization interface can reflect real-time changes in groundwater dynamics. Coordinate system alignment in GIS data conversion refers to the technique of mapping local coordinate system data to the global coordinate system, which can be achieved through the CPⅢ measurement network of tunnel construction control points. Data interpolation refers to using mathematical methods to fill data gaps between discrete detection points, which can be achieved by using the inverse distance weighting method (IDW) to generate a continuous pressure distribution surface. Structural layering in BIM model construction refers to dividing the display layers according to geological and engineering structural characteristics to enhance the readability and usability of the model. Risk overlay refers to visually displaying high-risk areas through a semi-transparent overlay layer, with the transparency inversely proportional to the risk level to highlight key areas. Flow direction calculation in dynamic arrow generation refers to determining the water flow direction based on vector synthesis results, which can be achieved using the right-hand rule. Velocity mapping refers to calculating the arrow length using a formula and limiting the maximum value to avoid visual clutter and clearly express water flow dynamics.

[0068] In detail, the above technical solution achieves real-time and intuitive marking of high-risk areas through a series of refined steps. First, the collected groundwater data is converted into the GIS-compatible GeoJSON format and mapped to a three-dimensional coordinate system. This process ensures data standardization and accurate positioning, avoiding positioning errors caused by format incompatibility. Second, a BIM model is built based on the tunnel design CAD drawings and overlaid with groundwater data, forming a comprehensive visualization model that allows for intuitive display of risk areas. In the three-dimensional model, pressure values ​​are represented by a red-to-blue gradient, and dynamic arrows indicate water flow direction. This design not only intuitively displays the pressure gradient but also reflects the dynamics of water flow in real time. Data standardization and dynamic updating steps further enhance the accuracy and real-time nature of visualization, solving the problem of untimely data updates in traditional methods. Coordinate system alignment and data interpolation steps in GIS data conversion compensate for the deficiencies of discrete point data, improving the continuity of visualization. Structural layering and risk overlay steps in BIM model construction enhance the understanding of geological structures and the ability to identify risks. Flow direction calculation and velocity mapping steps in dynamic arrow generation ensure the accuracy of arrow direction and length, making water flow dynamics clearly discernible. Overall, these steps work together to form a precise, real-time, and intuitive 3D visualization system that effectively assists in construction decision-making.

[0069] The above technical solution solves the problems of inaccurate data conversion, untimely updates, and unintuitive representation in existing visualization interfaces, significantly improving the accuracy and efficiency of construction decision-making. Furthermore, combining this solution with the aforementioned methods for early warning and handling of water inrush in deep and long tunnels further enhances the reliability and practicality of the overall technical system.

[0070] The above description is merely an exemplary embodiment of the present invention and does not limit the scope of protection of the present invention. Any equivalent structural transformations made based on the technical concept of the present invention and the contents of the specification and drawings of the present invention, or direct / indirect applications in other related technical fields, are included within the scope of protection of the present invention.

Claims

1. A method for early warning and handling of water inrush in deep and long tunnels, characterized in that, The methods for early warning and handling of water inrush in deep and long tunnels include: Infrared water detection equipment is installed at the tunnel face and sidewalls. The infrared water detection equipment emits infrared beams and receives reflected signals. The location, water content and flow direction of groundwater are identified based on the differences in signal strength and frequency, thus forming groundwater distribution data. The groundwater distribution data is compared with a preset water inrush risk threshold. If any area is found to have a groundwater pressure ≥1.5MPa or a water content ≥30% of the volume, it is determined to be a high-risk area. High-risk areas are marked using a 3D visualization interface and displayed with flashing red icons and pressure values ​​overlaid. Drainage holes are drilled in the high-risk area, and PVC drainage pipes with filters are installed in the drainage holes to divert groundwater to a collection well; wherein the diameter of the drainage holes is 50mm to 80mm, and the depth of the drainage holes is 1.2 to 1.5 times the diameter of the tunnel. A reinforced concrete layer is sprayed around the drainage hole; wherein the concrete is mixed in the following proportions by mass: cement: sand: aggregate: quick-setting agent = 1:2:3:0.05, and the thickness of the reinforced concrete layer is ≥10cm. Real-time monitoring of groundwater pressure changes after drainage; if the groundwater pressure does not drop below 1.0 MPa, the density of the drainage holes is increased to 2 to 3 per square meter, and the concrete reinforcement layer is sprayed to a thickness of ≥15 cm.

2. The method for early warning and handling of water inrush in deep and long tunnels as described in claim 1, characterized in that, The steps of arranging infrared water detection equipment at the tunnel face and sidewalls, emitting infrared beams and receiving reflected signals using the infrared water detection equipment, and identifying the location, water content, and flow direction of groundwater based on differences in signal strength and frequency to form groundwater distribution data include: An infrared water detection device is arranged every 5m along the longitudinal direction of the tunnel. Each set of infrared water detection devices includes one device at the center of the tunnel face and one device on each of the two side walls. The infrared water detection device emits infrared pulse signals at a frequency of 10kHz to 15kHz and collects the reflected signals every 30 seconds. The collected reflection signals are filtered to remove reflection noise from the rock interface, and the signals in the frequency range of 8kHz to 12kHz are retained for groundwater identification. When the water content is ≥25% in three consecutive samples from the same location, a data anomaly marker is triggered.

3. The method for early warning and handling of water inrush in deep and long tunnels as described in claim 1, characterized in that, The drilling angle of the drainage holes is perpendicular to the tunnel wall by ±10°, and the hole spacing is 1 / 10 to 1 / 5 of the length of the high-risk area.

4. The method for early warning and handling of water inrush in deep and long tunnels as described in claim 3, characterized in that, The inner diameter of the PVC drainage pipe is 30mm to 50mm, and the outer wall of the PVC drainage pipe is wrapped with permeable geotextile to filter mud and sand with a particle size ≤0.5mm.

5. The method for early warning and handling of water inrush in deep and long tunnels as described in claim 4, characterized in that, The permeable geotextile comprises 90% polypropylene fiber and 10% carbon fiber by weight.

6. The method for early warning and handling of water inrush in deep and long tunnels as described in any one of claims 1 to 5, characterized in that, Following the steps of drilling drainage holes in the high-risk area, installing PVC drainage pipes with filters inside the drainage holes, and diverting groundwater to a collection well, the method for early warning and handling of water inrush in deep and long tunnels further includes: A pressure sensor is installed at the outlet of the drain hole to monitor the drainage flow rate in real time. If the drainage flow rate is ≥5L / min for 10 minutes, the standby drain pump will be automatically started. The power of the drain pump is calculated to be 1.5kW for every 100L / min flow rate.

7. The method for early warning and handling of water inrush in deep and long tunnels as described in any one of claims 1 to 5, characterized in that, The step of spraying a concrete reinforcement layer around the drainage hole includes: Before spraying the concrete reinforcement layer, fiberglass anchors with a length of 1.5m to 2m are inserted at a spacing of 0.5m*0.5m to form a reinforcement zone; wherein, the fiberglass anchors comprise 60% epoxy resin matrix and 40% fiberglass by weight.

8. The method for early warning and handling of water inrush in deep and long tunnels as described in any one of claims 1 to 5, characterized in that, The method for early warning and handling of water inrush in deep and long tunnels includes real-time monitoring of groundwater pressure changes after drainage. If the groundwater pressure does not drop below 1.0 MPa, the density of the drainage holes is increased to 2 to 3 per square meter. Following the step of spraying the concrete reinforcement layer to a thickness ≥15 cm, the method further includes: Distributed fiber optic sensors are used to monitor the strain of the concrete layer. If the strain value is ≥200με, a reinforcement alarm for the reinforcement layer is triggered. During reinforcement, additional concrete with sprayed accelerator added to areas with excessive strain is added to increase the amount of concrete to 0.07 parts by weight, and the anchor rods are densified to a spacing of 0.3m*0.3m.

9. The method for early warning and handling of water inrush in deep and long tunnels as described in any one of claims 1 to 5, characterized in that, Before the step of arranging infrared water detection equipment at the tunnel face and sidewalls, using the infrared water detection equipment to emit infrared beams and receive reflected signals, and identifying the location, water content, and flow direction of groundwater based on differences in signal strength and frequency to form groundwater distribution data, the method for early warning and handling of water inrush in deep and long tunnels also includes: Gravity-based seepage monitors were installed on the tunnel arch. When the burial depth of the gravity-type seepage monitor is ≤50m, the preset water inrush risk threshold is 3L / (m²). 2 h); When the burial depth of the gravity-type seepage monitor is greater than 50m, the preset water inrush risk threshold is reduced by 0.5L / (m²) for every additional 10m of burial depth. 2 h) Calculation.

10. The method for early warning and handling of water inrush in deep and long tunnels as described in any one of claims 1 to 5, characterized in that, The steps involved in marking high-risk areas using a 3D visualization interface and displaying them with flashing red icons and pressure values ​​overlaid include: The collected data on the location, water content, and flow direction of the groundwater are converted into GIS-compatible GeoJSON format and mapped to the tunnel's three-dimensional coordinate system. A BIM model is created based on CAD format drawings of tunnel design, and a hybrid 3D model is generated by overlaying groundwater data. In the three-dimensional model, pressure values ​​are represented by a gradient from red to blue; where red represents a pressure value ≥1.5MPa and blue represents a pressure value ≤0.5MPa. The direction of water flow is represented by dynamic arrows, and the length of the arrows is proportional to the flow velocity.

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