An exhaust shaft excavation support and ventilation dust removal integrated construction method

Abstract

The application discloses a kind of exhaust shaft excavation support and ventilation dust removal integrated construction method, it is related to pumped storage power station engineering construction technical field, the method includes construction preparation and scheme design, side slope pretreatment and passive protection, layered excavation and synchronous ventilation dust removal, synchronous support construction and dust control, monitoring and dynamic adjustment, process acceptance and finishing step, by configuring intelligent sensing monitoring terminal and with ventilation dust removal system, construction equipment control system linkage, realize excavation, support, ventilation dust removal Collaborative work and intelligent control.The application solves the problems of traditional construction process separation, serious dust pollution, insufficient side slope stability and other problems, has the characteristics of short construction period, high safety factor, good dust control effect, good engineering quality, and realizes digital management of the whole construction process, can provide technical reference for similar projects, applicable to pumped storage power station exhaust shaft and other underground engineering construction.

Description

Technical Field

[0001] This invention relates to the field of pumped storage power station construction technology, specifically to an integrated construction method for ventilation shaft excavation, support, ventilation, and dust removal. Background Technology

[0002] As a core regulating facility in the new power system, pumped storage power stations face numerous technical challenges in the construction of their underground powerhouse caverns and ventilation shafts. Ventilation shafts are characterized by large excavation diameters, deep depths, and high requirements for slope stability. Traditional construction methods separate excavation, support, and ventilation / dust removal processes: on the one hand, after slope excavation, subsequent processes cannot proceed until support work is completed, leading to extended construction periods and increased susceptibility to collapse risks due to geological conditions; on the other hand, the large amounts of dust generated during excavation are difficult to remove quickly, affecting the health of construction workers and reducing construction efficiency. Existing ventilation systems are mostly single-function designs, unable to coordinate with the excavation and support processes, resulting in poor dust control.

[0003] In existing technologies, wet sprayed concrete construction suffers from problems such as high rebound rate and serious waste of resources. Furthermore, the ventilation system lacks targeted optimization, making it difficult to adapt to the complex spatial structure of the exhaust shaft. The dust transport pattern is unclear, resulting in low dust removal efficiency.

[0004] Therefore, we propose an integrated construction method for ventilation shaft excavation and support with ventilation and dust removal. Summary of the Invention

[0005] The purpose of this invention is to provide an integrated construction method for ventilation shaft excavation, support, ventilation, and dust removal, which solves the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: an integrated construction method for excavation, support, ventilation, and dust removal of exhaust shafts, comprising the following steps:

[0007] Step 1: Construction preparation and scheme design. Conduct a detailed geological survey of the ventilation shaft construction area and complete technical and safety briefings. Configure integrated construction equipment with intelligent sensor monitoring terminals and related construction materials. Optimize the ventilation network layout based on CFD numerical simulation technology and link the intelligent sensor monitoring terminals with the ventilation and dust removal system and the construction equipment control system.

[0008] Step 2: Slope pretreatment and passive protection. The slope is cleared manually from top to bottom, and the settlement displacement and rock stress at the top of the slope are monitored in real time through intelligent sensor monitoring terminals. A passive protection net with a height of 5m and a protection energy level of not less than 750KJ is installed at the top of the slope, and stress sensors are set at key nodes. A water interception ditch is excavated below the passive protection net and a water level sensor is installed. The water interception ditch is made of C25W6F50 concrete and an expansion joint with a width of 10mm is set every 12m. The joint is filled with closed-cell foam board.

[0009] Step 3: Layered excavation and simultaneous ventilation and dust removal. Excavation is carried out in two stages from top to bottom using excavators and manual labor. The first stage excavation height is 3m, and the second stage excavation height is 7m. The excavation height of each layer is controlled at 3-4m with a 0.3-0.5m protective layer reserved. During the excavation process, intelligent sensor monitoring terminals collect dust concentration data in real time. The ventilation and dust removal system automatically adjusts the fan power and suction power of the dust collection device according to the data to ensure that the dust concentration at the working surface is ≤10mg / m³. The excavated soil and rock are transported to the designated spoil disposal site by dump trucks. The transport vehicles are equipped with GPS positioning and dust monitoring devices, and the transport roads are regularly watered to reduce dust.

[0010] Step 4: Synchronous support construction and dust control. Immediately after the excavation of each layer, φ25, L=6m cement mortar anchors are installed at 2m×2m intervals, with 10cm exposed. Stress sensors are installed at the tail of the anchors. Simultaneously, φ50, L=5m drainage holes are installed at 4m×4m intervals. DN40PE drainage pipes with L=2m and an upward inclination of 10° are inserted inside. The pipe body and inner end are wrapped with geotextile. φ8 steel mesh is laid, with φ12 keel steel bars. The steel mesh is welded and fixed to the anchors. C30 concrete with rebound-reducing nano-composite admixture is sprayed to a thickness of 10cm. During the spraying operation, the spraying pressure of the wet spraying machine and the parameters of the ventilation system are automatically adjusted according to the dust concentration data.

[0011] Step 5: Monitoring and dynamic adjustment. The slope displacement, rock stress, anchor bolt force, concrete curing environment, dust concentration, and ventilation parameters are continuously monitored 24 hours a day. The intelligent sensor monitoring terminal collects data every 5 minutes and uploads it to the control platform in real time. The control platform analyzes the data and links with relevant systems to adjust parameters or issue early warnings.

[0012] Step Six: Process Acceptance and Completion. Each process is subject to a three-inspection system. A quality traceability report is generated by combining the data collected by the intelligent monitoring system throughout the process. A full-process construction data report is submitted during the overall acceptance.

[0013] In a preferred embodiment of the present invention, the intelligent sensing and monitoring terminal integrates temperature and humidity, dust concentration, rock stress, and water level sensors.

[0014] In a preferred embodiment of the present invention, the intercepting ditch is 1m wide and 1.05m high on the outer side, with φ12 steel bars arranged horizontally at 200mm intervals and φ8 steel bars arranged longitudinally at 200mm intervals.

[0015] In a preferred embodiment of the present invention, the spacing between the steel mesh is 20cm×20cm, and the spacing between the reinforcing bars is 2m×2m.

[0016] In a preferred embodiment of the present invention, the anchor rod is drilled using a Gaozan LX200 drilling rig, and grouting is performed using a GYZ-4D screw-type integrated grouting machine. The grouting pressure is controlled at 0.3-0.5 MPa, and the insertion length of the anchor rod body is not less than 95% of the design length.

[0017] In a preferred embodiment of the present invention, in step five, the horizontal displacement warning value is 2-3 mm / d of daily deformation rate and 20-30 mm of cumulative displacement, and the control value is 3-5 mm / d of daily deformation rate and 30-50 mm of cumulative displacement. The vertical displacement warning value is 1-2 mm / d of daily deformation rate and 10-15 mm of cumulative displacement, and the control value is 2-3 mm / d of daily deformation rate and 15-20 mm of cumulative displacement.

[0018] In a preferred embodiment of the present invention, the ventilation system is equipped with a high-power fan at the top of the shaft and dust suction ports are arranged at the excavation face to ensure that the wind speed at the working face is ≥0.5m / s.

[0019] In a preferred embodiment of the present invention, during the concrete curing process, when the humidity of the curing environment is detected to be below 60%, the spray curing device is activated.

[0020] In a preferred embodiment of the present invention, when the dust concentration exceeds 8 mg / m³, the ventilation and dust removal system automatically starts the backup fan and increases the dust suction power.

[0021] In a preferred embodiment of the present invention, the integrated construction equipment further includes an excavator, a screw air compressor, and a total station.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0023] This invention integrates excavation, support, and ventilation / dust removal processes into a unified, collaborative design, incorporating intelligent sensing and monitoring technologies with multi-system linkage. This achieves a deep fusion of layered excavation and synchronous support, real-time dust removal, and intelligent monitoring. This not only significantly shortens the construction cycle and avoids the risk of collapse caused by prolonged slope exposure, but also enables precise control of construction parameters through real-time data support, improving construction safety and project quality. Based on CFD numerical simulation-optimized ventilation network layout, combined with real-time dust concentration feedback from the intelligent monitoring system, the ventilation / dust removal system can automatically and adaptively adjust its operating status, forming a comprehensive dust control system that effectively reduces construction dust pollution and protects the health of construction workers. Simultaneously, intelligent monitoring... The system's real-time monitoring of key parameters such as rock mass stress and anchor bolt stress can provide early warnings of potential support risks and prevent support structure failure. The addition of a rebound-reducing nano-composite admixture to the shotcrete, combined with optimized anchor bolt construction techniques and steel mesh laying methods, reduces the rebound rate of wet-mixed shotcrete, improving the stability and durability of the support structure. Furthermore, the intelligent monitoring system's real-time monitoring of the concrete curing environment and dynamic adjustment of curing measures further ensures that the concrete strength meets standards and guarantees excellent project quality. Intelligent sensing monitoring and multi-system linkage technology enable digital and visual management of the entire construction process, significantly improving construction management efficiency and allowing managers to monitor the construction status in real time and address problems promptly. Attached Figure Description

[0024] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0025] Figure 1 This is a flowchart of an integrated construction method for ventilation shaft excavation, support, ventilation, and dust removal according to the present invention. Detailed Implementation

[0026] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0027] Example

[0028] The ventilation shaft in this embodiment is the underground powerhouse cavern of a pumped storage power station project. The ventilation shaft has an excavation diameter of 7.5m and a total height of approximately 92m. The exposed strata in the project area are mainly the Lower Cretaceous Xishantou Formation (K1x), containing conglomerate lithic crystal tuff and lithic crystal tuff, with some welded tuff (weakly welded), and locally interbedded with tuffaceous siltstone and grayish-green and grayish-purple breccia tuff. The Quaternary overburden is mainly composed of residual slope deposits (Q4edl), alluvial deposits (Q4pl+dl), and artificial deposits (Q4s). The thickness of the residual deposits is generally 0.4–1.0m, the thickness of the alluvial deposits is 1.0–2.5m, and the thickness of the artificial deposits revealed by boreholes is 21.10m.

[0029] The power station has a total installed capacity of 1200MW (4×300MW). After completion, it will undertake tasks such as peak shaving, valley filling, and energy storage for the Zhejiang power grid. As an important supporting facility for the power station, the construction quality of the ventilation shaft directly affects the overall operational safety and stability of the power station. This project adopts the integrated construction method of this invention.

[0030] Construction preparation and scheme design

[0031] On-site survey and technical briefing: A professional survey team was formed to conduct precise surveying and layout of the construction area using a total station. Combined with geological drilling data, the distribution of strata lithology, geological structure, and groundwater occurrence were clarified, and a detailed survey report was generated. Technical briefings were conducted with the construction, design, supervision, and construction parties, focusing on clarifying the slope excavation ratio of 1:0.75, support structure parameters, ventilation and dust control requirements, and key safety control points, ensuring that construction personnel fully understand the construction standards.

[0032] Equipment and material preparation:

[0033] Integrated construction equipment configuration: excavator, boom drilling rig, wet spraying machine, screw air compressor, ventilation and dust removal system (including 2 high-power fans and 4 dust collection devices), intelligent sensor monitoring terminal (20 units, integrating temperature, humidity, dust concentration, rock stress, and water level sensors), 1 GYZ-4D screw grouting machine, 2 300kw diesel generators, rebar processing equipment (automatic rebar straightening and cutting machine, rebar cutting machine, GW45 rebar bending machine), and dump truck.

[0034] Construction material preparation: 90m³ of C30 shotcrete, 96m³ of C25W6F50 intercepting ditch concrete, 226 φ25 cement mortar anchor rods (6m long each), 5.86t of φ8 steel mesh, 4.82t of φ12 keel steel bars, 513㎡ of passive protection netting (protection energy level 750KJ), 114m of DN40PE drainage pipe, rebound-reducing nano-composite admixture, closed-cell foam board, geotextile, etc. All materials were inspected and qualified before entering the site. Cement, steel bars and other major materials are provided with quality certificates, and admixtures are provided with performance test reports.

[0035] Collaborative Design of Ventilation, Dust Suppression, and Intelligent Monitoring Systems: Based on CFD numerical simulation technology, a three-dimensional airflow coupling model of the exhaust shaft is constructed to simulate dust transport patterns at different construction stages and optimize the ventilation network layout. Two high-power fans (1500 m³ / h each) are installed at the top of the shaft, and four dust extraction ports (adjustable suction range 0.3-0.8 MPa) are arranged around the excavation face, forming a two-way ventilation mode of "top air supply + excavation face dust extraction" to ensure an air velocity ≥0.5 m / s at the working face. The intelligent sensor monitoring terminal is linked with the ventilation and dust suppression system and the construction equipment control system via a wireless local area network to build a remote control platform, enabling real-time data transmission, automatic equipment control, and anomaly warning functions.

[0036] III. Slope Pretreatment and Passive Protection

[0037] Manual slope clearing: Professional construction personnel remove weeds, rocks, and unstable rocks from the slope surface from top to bottom. During the clearing process, two intelligent sensor monitoring terminals are used to monitor the settlement displacement at the top of the slope and the rock mass stress, with monitoring data uploaded to the control platform every 5 minutes. If signs of crack development are found in the local rock mass, slope clearing is immediately suspended, and small machinery is used in conjunction with manual prying to remove the unstable rocks. Construction resumes after the hazard is eliminated, ensuring that there is no risk of collapse during the slope clearing process.

[0038] Passive protection net installation: A passive protection net, 5m high, is installed at the top of the slope according to design requirements. It is fixed with φ25 anchor bolts (anchor bolt spacing of 2m). Stress sensors are installed at four key stress nodes of the net to monitor its stress state in real time (the maximum allowable stress value is 50MPa). After installation, a stability test is conducted by manually pulling the edges of the net to ensure it is firmly fixed and free from loosening.

[0039] Interception Ditch Construction: An interception ditch will be excavated below the passive protection netting. The ditch will be 1m wide and 1.05m high on the outer side. An excavator will be used to outline the ditch, followed by manual trimming. During excavation, the slope of the trench will be controlled at 1:0.3 to avoid over-excavation or under-excavation. The reinforcement of the interception ditch will consist of transverse φ12 steel bars (spaced 200mm) and longitudinal φ8 steel bars (spaced 200mm). C25W6F50 concrete can only be poured after the reinforcement is tied and approved by the supervisor. An expansion joint (10mm wide) will be installed every 12m, filled with closed-cell foam board to ensure a good seal. Three water level sensors will be installed in the middle section and at both ends of the interception ditch to monitor the drainage status in real time. When the water level exceeds the design elevation by 5cm, the control platform will automatically issue an early warning, prompting the dredging of the drainage channel.

[0040] IV. Layered Excavation and Simultaneous Ventilation and Dust Removal

[0041] Staged excavation construction: Excavation is carried out in two stages from top to bottom using excavators and manual labor. The first stage excavation height is 3m, and the second stage excavation height is 7m. The excavation height of each layer is controlled at 3-4m, and a 0.3-0.5m protective layer is reserved for manual slope trimming. Before excavation, the outline of the excavation boundary is marked with lime according to the survey and layout marks. During the excavation process, the excavator operates in layers along the outline to avoid excessive disturbance to the slope rock mass. Manual labor is responsible for trimming the slope surface to ensure that the slope ratio meets the design requirement of 1:0.75.

[0042] Intelligent control of ventilation and dust removal during excavation: During excavation operations, the ventilation and dust removal system and intelligent sensor monitoring terminal are activated, and the terminal collects real-time dust concentration data at the excavation surface. When the dust concentration is ≤8mg / m³, the ventilation and dust removal system operates according to normal parameters (fan power 60%, suction power of the dust collection device 0.3MPa); when the dust concentration exceeds 8mg / m³, the control platform automatically instructs the ventilation and dust removal system to start the backup fan, and simultaneously increases the suction power of the dust collection device to 0.5-0.8MPa until the dust concentration drops below 10mg / m³. During construction, the wind speed field distribution is monitored in real time through the control platform to ensure that the wind speed at the working face is always maintained between 0.5-1.0m / s, effectively suppressing dust diffusion.

[0043] Slag Transportation: The excavated soil and rock are transported by excavator to a temporary stockpile area at the bottom of the slope (approximately 30 square meters), and then loaded onto dump trucks by loaders and transported to a designated spoil disposal site (approximately 2 kilometers from the construction area). Transport vehicles are equipped with GPS positioning and dust monitoring devices. A control platform monitors the transport route and vehicle dust levels in real time. The transport roads are watered every 2 hours (using water trucks at a spraying intensity of 2 L / m²) to prevent secondary dust pollution.

[0044] V. Synchronous Support Construction and Dust Control

[0045] Anchor Bolt Construction: Anchor bolt construction should be completed within 24 hours after each layer of excavation. First, use a Gaozan LX200 drilling rig to drill holes at the designed locations (2m x 2m spacing), with a hole diameter of 42mm. The drilling direction should be as perpendicular as possible to the main structural plane of the rock strata, with an allowable deviation of ±15mm. After drilling, use high-pressure air to remove dust from the holes, ensuring they are clean and free of debris. Use a GYZ-4D screw-type grouting machine for grouting, controlling the grouting pressure at 0.3-0.5 MPa. Insert the grouting pipe 5-10cm from the bottom of the hole, and slowly and evenly pull it out as cement mortar is injected. Immediately insert a φ25 cement mortar anchor bolt, ensuring the bolt insertion length is not less than 95% of the designed length (i.e., not less than 5.7m). If no mortar flows out of the hole, pull out the bolt and re-grout. Install a stress sensor at the end of every 10 anchor bolts to monitor the anchor bolt's stress state in real time, ensuring uniform stress distribution (design maximum allowable stress 30MPa).

[0046] Drainage hole construction: Drainage hole construction is carried out simultaneously with anchor bolt construction. The drainage holes have a diameter of φ50, a length of 5m, and a spacing of 4m×4m. After drilling, impurities are cleaned from the holes, and DN40PE drainage pipes with a length of 2m and an upward inclination of 10° are inserted. The pipe body and inner end are wrapped with geotextile (to prevent silt blockage) to ensure smooth drainage. Based on the water level sensor data in the intercepting ditch, if drainage is found to be obstructed in a certain area, the density of drainage holes in that area is adjusted in a timely manner or high-pressure water is used for dredging.

[0047] Reinforcing mesh installation and shotcrete support: After the anchor bolts are installed, lay φ8 reinforcing mesh (20cm x 20cm spacing) and φ12 reinforcing bars (2m x 2m spacing). The reinforcing mesh is welded to the anchor bolts, with welding points spaced no more than 50cm apart to ensure a secure connection. Before shotcreting C30 concrete, manually remove loose soil, gravel, and debris from the surface to be sprayed. Use a GYP-9D hydraulic wet shotcrete machine to spray concrete (10cm thickness). Add a rebound-reducing nano-composite admixture (0.8% of the cementitious material mass) to the concrete to balance pumpability and sprayability, reducing the concrete rebound rate to below 15%. During shotcreting, the intelligent monitoring system automatically adjusts the wet shotcrete machine's spraying pressure (0.4-0.6Mpa) and ventilation system parameters based on dust concentration data to reduce dust diffusion during spraying. The spraying sequence is from top to bottom, concave to convex, ensuring uniform concrete coverage without voids.

[0048] VI. Monitoring and Dynamic Adjustment

[0049] Comprehensive intelligent monitoring: Twenty intelligent sensor monitoring terminals continuously monitor slope displacement, rock stress, anchor bolt stress, concrete curing environment (temperature and humidity), dust concentration, and ventilation parameters 24 hours a day. Monitoring data is uploaded to the control platform every 5 minutes, generating dynamic change curves. Specifically, the warning value for horizontal slope displacement is a daily deformation rate of 2-3 mm / d and a cumulative displacement of 20-30 mm, while the control value is a daily deformation rate of 3-5 mm / d and a cumulative displacement of 30-50 mm; the warning value for vertical displacement is a daily deformation rate of 1-2 mm / d and a cumulative displacement of 10-15 mm, while the control value is a daily deformation rate of 2-3 mm / d and a cumulative displacement of 15-20 mm; the warning value for anchor bolt stress is 25 MPa, and the control value is 30 MPa; the concrete curing environment temperature is controlled between 5-35℃, and the humidity is not lower than 60%; the dust concentration control value is 10 mg / m³.

[0050] Multi-system coordinated adjustment: The control platform comprehensively analyzes monitoring data. When the slope displacement approaches the warning value, it automatically prompts a halt to construction and pushes reinforcement suggestions (such as increasing the density of anchor bolts, adding steel mesh, etc.). When the dust concentration is abnormal, the ventilation and dust removal system automatically adjusts the fan power and suction power of the dust collection device. When the humidity of the concrete curing environment is below 60%, an early warning is issued and the spray curing device is automatically activated (spray intensity 1L / ㎡・h). When the anchor bolt stress exceeds the warning value, construction personnel are promptly notified to inspect the support structure and take reinforcement measures. During construction, dedicated personnel are assigned to maintain the monitoring equipment to ensure its normal operation and the accuracy and reliability of the monitoring data.

[0051] VII. Process Acceptance and Finishing

[0052] Sub-project acceptance: Each process strictly adheres to the "three-inspection system" (self-inspection by the construction team, mutual inspection by the project department, and acceptance by the supervisor). After passing the self-inspection, the construction team submits a self-inspection report; the project department organizes mutual inspections, focusing on whether the process quality meets design requirements and whether the monitoring data is normal; after passing the mutual inspection, the report is submitted to the supervisor for acceptance. The supervisory engineer conducts acceptance through on-site testing and review of documents (including intelligent monitoring data reports), etc. Only after the acceptance is passed and the supervisor signs the acceptance opinion can the next process begin. For example, during the acceptance of anchor bolt construction, an anchor bolt pull-out test is used to test the anchoring force (design anchoring force ≥150KN), with a random sampling rate of 5%, and all sampled results must meet the requirements; during the acceptance of shotcrete, the core drilling method is used to test the concrete strength (design strength ≥30MPa), while simultaneously checking the concrete thickness and appearance quality, ensuring there are no defects such as exposed reinforcement or cracks.

[0053] Overall Acceptance and Completion: After all construction is completed, the construction, surveying, design, supervision, construction, and monitoring units will conduct an overall acceptance inspection. The inspection will cover slope stability, support structure quality, drainage effect, operation of the ventilation and dust removal system, and the completeness of construction documentation. The construction unit will submit a full-process construction data report, quality traceability report, sub-item project acceptance records, material qualification certificates, and other documents. After acceptance, temporary facilities at the construction site will be dismantled, construction waste will be cleaned up, and the site and surrounding environment will be thoroughly cleaned, ensuring that the work is completed, materials are removed, and the site is clean.

[0054] This embodiment, through the integrated construction method of the present invention, achieves coordinated operation and intelligent control of ventilation shaft excavation, support, ventilation and dust removal. No safety accidents occurred during the construction process. The daily deformation rate of horizontal slope displacement was ≤2mm / d, and the cumulative displacement was ≤18mm. The daily deformation rate of vertical displacement was ≤1.5mm / d, and the cumulative displacement was ≤12mm, all within the warning value range. The dust concentration at the work site was consistently controlled below 10mg / m³, effectively protecting the health of construction personnel. The rebound rate of shotcrete was reduced to below 15%, saving construction materials. The project quality reached excellent standards.

[0055] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or basic characteristics. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

[0056] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A construction method integrating excavation, support, ventilation, and dust removal for exhaust shafts, characterized in that: The methods and steps include the following: Step 1: Construction preparation and scheme design. Conduct a detailed geological survey of the ventilation shaft construction area and complete technical and safety briefings. Configure integrated construction equipment with intelligent sensor monitoring terminals and related construction materials. Optimize the ventilation network layout based on CFD numerical simulation technology and link the intelligent sensor monitoring terminals with the ventilation and dust removal system and the construction equipment control system. Step 2: Slope pretreatment and passive protection. The slope is cleared manually from top to bottom, and the settlement displacement and rock stress at the top of the slope are monitored in real time through intelligent sensor monitoring terminals. A passive protection net with a height of 5m and a protection energy level of not less than 750KJ is installed at the top of the slope, and stress sensors are set at key nodes. A water interception ditch is excavated below the passive protection net and a water level sensor is installed. The water interception ditch is made of C25W6F50 concrete and an expansion joint with a width of 10mm is set every 12m. The joint is filled with closed-cell foam board. Step 3: Layered excavation and simultaneous ventilation and dust removal. Excavation is carried out in two stages from top to bottom using excavators and manual labor. The first stage excavation height is 3m, and the second stage excavation height is 7m. The excavation height of each layer is controlled at 3-4m with a 0.3-0.5m protective layer reserved. During the excavation process, intelligent sensor monitoring terminals collect dust concentration data in real time. The ventilation and dust removal system automatically adjusts the fan power and suction power of the dust collection device according to the data to ensure that the dust concentration at the working surface is ≤10mg / m³. The excavated soil and rock are transported to the designated spoil disposal site by dump trucks. The transport vehicles are equipped with GPS positioning and dust monitoring devices, and the transport roads are regularly watered to reduce dust. Step 4: Synchronous support construction and dust control. Immediately after the excavation of each layer, φ25, L=6m cement mortar anchors are installed at 2m×2m intervals, with 10cm exposed. Stress sensors are installed at the tail of the anchors. Simultaneously, φ50, L=5m drainage holes are installed at 4m×4m intervals. DN40PE drainage pipes with L=2m and an upward inclination of 10° are inserted inside. The pipe body and inner end are wrapped with geotextile. φ8 steel mesh is laid, with φ12 keel steel bars. The steel mesh is welded and fixed to the anchors. C30 concrete with rebound-reducing nano-composite admixture is sprayed to a thickness of 10cm. During the spraying operation, the spraying pressure of the wet spraying machine and the parameters of the ventilation system are automatically adjusted according to the dust concentration data. Step 5: Monitoring and dynamic adjustment. The slope displacement, rock stress, anchor bolt force, concrete curing environment, dust concentration, and ventilation parameters are continuously monitored 24 hours a day. The intelligent sensor monitoring terminal collects data every 5 minutes and uploads it to the control platform in real time. The control platform analyzes the data and links with relevant systems to adjust parameters or issue early warnings. Step Six: Process Acceptance and Completion. Each process is subject to a three-inspection system. A quality traceability report is generated by combining the data collected by the intelligent monitoring system throughout the entire process. A full-process construction data report is submitted during the overall acceptance.

2. The integrated construction method for excavation, support, ventilation, and dust removal of exhaust shafts according to claim 1, characterized in that: The intelligent sensing and monitoring terminal integrates sensors for temperature and humidity, dust concentration, rock stress, and water level.

3. The integrated construction method for excavation, support, ventilation, and dust removal of exhaust shafts according to claim 1, characterized in that: The intercepting ditch is 1m wide and 1.05m high on the outer side. It is equipped with φ12 steel bars arranged horizontally with a spacing of 200mm, and φ8 steel bars arranged longitudinally with a spacing of 200mm.

4. The integrated construction method for excavation, support, ventilation, and dust removal of exhaust shafts according to claim 1, characterized in that: The spacing between rows of the steel mesh is 20cm×20cm, and the spacing between rows of the reinforcing bars is 2m×2m.

5. The integrated construction method for excavation, support, ventilation, and dust removal of exhaust shafts according to claim 1, characterized in that: The anchor bolts are drilled using a Gaozan LX200 drilling rig, and grouting is performed using a GYZ-4D screw-type integrated grouting machine. The grouting pressure is controlled at 0.3-0.5 MPa, and the insertion length of the anchor bolt body is not less than 95% of the design length.

6. The integrated construction method for excavation, support, ventilation, and dust removal of exhaust shafts according to claim 1, characterized in that: In step five, the warning value for horizontal displacement is 2-3 mm / d of daily deformation rate and 20-30 mm of cumulative displacement, while the control value is 3-5 mm / d of daily deformation rate and 30-50 mm of cumulative displacement. The warning value for vertical displacement is 1-2 mm / d of daily deformation rate and 10-15 mm of cumulative displacement, while the control value is 2-3 mm / d of daily deformation rate and 15-20 mm of cumulative displacement.

7. The integrated construction method for excavation, support, ventilation, and dust removal of exhaust shafts according to claim 1, characterized in that: The ventilation system is equipped with a high-power fan at the top of the shaft and dust extraction ports are arranged at the excavation face to ensure that the wind speed at the working face is ≥0.5m / s.

8. The integrated construction method for excavation, support, ventilation, and dust removal of exhaust shafts according to claim 1, characterized in that: During the concrete curing process, when the humidity of the curing environment is detected to be below 60%, the spray curing device is activated.

9. The integrated construction method for excavation, support, ventilation, and dust removal of exhaust shafts according to claim 1, characterized in that: When the dust concentration exceeds 8mg / m³, the ventilation and dust removal system will automatically start the backup fan and increase the suction power.

10. The integrated construction method for excavation, support, ventilation, and dust removal of a ventilation shaft according to claim 1, characterized in that: The integrated construction equipment also includes excavators, screw air compressors, and total stations.

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