A grading dynamic treatment construction method for tunnel crossing abandoned roadway
Patent Information
- Application Number
- CN202611033268.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-07-13
- Publication Date
- 2026-10-16
AI Technical Summary
(1) 经济性差：未对巷道与隧道的空间相对关系（如距离、方位）进行精细化分析，导致对安全风险极低或无影响的区段也进行了高成本处治，造成工程资源的大量浪费
(1) 经济效益显著：通过引入“L/D”判据进行精准分级，避免了在无影响区和低风险区的过度处治，可显著节约工程成本（估算可达20% ~ 40%），具有突出的经济性。
Smart Images
Figure CN122919409A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of tunnel and underground engineering construction technology, specifically relating to a safe and economical treatment system and construction method for tunnels in mountainous highways, railways, etc., when crossing existing abandoned coal mine goaf areas and roadways. Background Technology
[0002] With the deepening of transportation infrastructure construction in my country, newly built tunnels often need to traverse abandoned mining areas left over from the past. These abandoned tunnels have unstable structures, posing a serious threat to tunnel construction safety. Currently, the industry's conventional approach to this problem is a "one-size-fits-all" method of high-strength grouting or concrete backfilling throughout the entire tunnel. While this method ensures safety to a certain extent, it has the following significant drawbacks: (1) Poor economic efficiency: The spatial relationship between the roadway and the tunnel (such as distance and orientation) was not analyzed in detail, resulting in high-cost treatment of sections with extremely low or no safety risk, causing a large waste of engineering resources.
[0003] (2) Lack of specificity: The backfill or reinforcement design is independent of the tunnel excavation method and blasting control, and fails to form a coordinated overall construction plan. Under excavation disturbance, the interaction mechanism between the backfill, surrounding rock and the initial support of the tunnel is complex and can easily lead to uncontrollable deformation.
[0004] (3) Low construction efficiency: A uniform treatment plan often leads to complex procedures and extended construction period, making it difficult to adapt to the need for dynamic adjustment under complex geological conditions.
[0005] Therefore, there is an urgent need for a treatment technology that can accurately classify risks based on risk levels and dynamically coordinate with the tunnel excavation process, so as to achieve economical and efficient construction while ensuring safety. Summary of the Invention
[0006] To address the aforementioned problems in existing technologies, this invention aims to provide a graded dynamic treatment construction method for tunnels traversing abandoned roadways. This method can accurately classify risks based on the spatial relationship between the roadway and the tunnel, and match differentiated treatment structures. Simultaneously, it dynamically couples the treatment design with tunnel excavation and blasting vibration control, thereby achieving safe, economical, and efficient construction goals.
[0007] To achieve the above objectives, the present invention provides the following technical solution: A graded dynamic treatment construction method for tunnels passing through abandoned roadways, characterized by the following steps: S1. Calculate the vertical distance L between the top of the abandoned tunnel and the bottom of the tunnel within the abandoned tunnel treatment area, as well as the outer diameter D of the tunnel. S2. Along the length of the abandoned tunnel, the treatment area is divided into different impact zones according to the L / D value as follows: Areas with an L / D ratio greater than 3 in the abandoned alleyway treatment area are designated as no-impact zones. The area within the abandoned tunnel treatment zone with a length of 1.5 ≤ L / D ≤ 3 is designated as a warning zone; Areas with L / D < 1.5 in the abandoned roadway treatment area are designated as treatment zones; S3. Before tunnel construction, implement graded dynamic treatment measures for different affected areas: No special treatment will be given to areas without impact. The area under attention was backfilled using standard procedures. Composite structure support construction shall be carried out in the measure area; S4, Tunnel excavation.
[0008] Preferably, the conventional backfilling construction specifically involves constructing a retaining wall at one end of the warning zone along the length of the abandoned tunnel, then backfilling the tunnel slag into the warning zone, and finally constructing a retaining wall at the other end of the warning zone.
[0009] Preferably, the construction of the composite structure support specifically includes: Along the length of the abandoned tunnel, sealing walls are constructed sequentially at intervals of 4-6 m within the measure area to divide the measure area into several backfill sections; During the construction of each sealing wall, tunnel slag is backfilled in layers between each sealing wall under construction and the previous completed sealing wall. A pouring space for the sealing top slab is reserved above the tunnel slag, and a conveying port is reserved at the top of the sealing wall. Concrete is then poured into the pouring space through the conveying port to form the sealing top slab, thus completing the backfilling construction of the corresponding backfill section.
[0010] More preferably, the sealing wall includes two thick end walls located at the outermost end of the measure area and a thin middle wall located between the thick end walls; The thick end wall is formed by casting reinforced concrete, with a thickness controlled at 180-220 cm; the thin middle wall is formed by brickwork, with a thickness controlled at 40-60 cm. More preferably, the sealing top plate is made of C15 concrete with a thickness of 50-70 cm.
[0011] A further preferred embodiment includes installing drainage pipes along the length of the abandoned tunnel at both corners of the tunnel floor slab within the protection zone and wrapping them with geotextile fabric, wherein drainage holes are evenly distributed on the side of the drainage pipe facing the interior of the abandoned tunnel.
[0012] Preferably, in step S4, when the abandoned roadway treatment area includes a warning area, the settlement rate of the abandoned roadway in the warning area is monitored in real time when the tunnel construction reaches the crossing area, and the tunnel construction is dynamically adjusted according to the settlement rate.
[0013] More preferably, the crossing area is the tunnel construction section within 15-20 m on both sides of the boundary of the abandoned roadway.
[0014] More preferably, the dynamic adjustment involves reducing the single excavation advance of the tunnel and using micro-differential controlled blasting technology when the settlement rate exceeds the warning value, thereby controlling the peak blasting vibration velocity to within 3 cm / s.
[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) Significant economic benefits: By introducing the “L / D” criterion for precise classification, overtreatment in no-impact and low-risk areas is avoided, which can significantly save engineering costs (estimated to be 20% to 40%), demonstrating outstanding economic efficiency.
[0016] (2) High safety and strong targeting: For high-risk (measured area) roadways, the innovative composite structure of "thick end wall + thin middle wall + blast muck + concrete roof" provides graded constraints and drainage channels, effectively suppressing the roadway's compression deformation and water inrush risk. The synergistic control of CRD construction method and micro-differential blasting minimizes construction disturbance.
[0017] (3) Dynamic and controllable with strong adaptability: The “design-construction-monitoring-feedback-adjustment” process is formed into a closed loop. By dynamically adjusting key parameters such as the spacing of the sealing wall and the excavation advance through real-time monitoring data, the construction plan can adapt to complex geological conditions and greatly improve the safety redundancy and controllability of the project. Attached Figure Description
[0018] Figure 1 This is a schematic diagram of the graded dynamic treatment construction method of the present invention; Figure 2 for Figure 1 Cross-sectional view at point AA; Figure 3 for Figure 1 Cross-sectional view at point BB; Figure 4 for Figure 1 Cross-sectional view at point C; Figure 5 A schematic diagram illustrating the simultaneous construction of the sealing wall and the backfilling of tunnel slag; Figure 6 A bird's-eye view of the tunnel passing through an abandoned alleyway; Figure 7A schematic diagram showing the division of the abandoned alleyway treatment area into one attention zone and one measure zone; Figure 8 A schematic diagram showing that the treatment area for abandoned alleyways is divided into one no-impact zone, one warning zone, and one measure zone; The meanings of the markings in the above diagrams are as follows: Abandoned roadway treatment area 1, Abandoned roadway 2, Tunnel 3, Sealing wall 4, Thick end wall 401, Thin middle wall 402, Backfill section 5, Drainage pipe 6, Tunnel muck 7, Conveying port 8, Sealing roof 9, Retaining wall 10, Crossing area 11. Detailed Implementation
[0019] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be noted that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the invention. Example 1
[0020] This embodiment provides a graded dynamic treatment construction method for tunnels crossing abandoned roadways. Please refer to [link to relevant documentation]. Figures 1 to 8 It includes the following steps: S1. Through geological survey and measurement, accurately locate the abandoned tunnel, and calculate the vertical distance L between the top of the abandoned tunnel 2 and the bottom of the tunnel 3 within the abandoned tunnel treatment area 1, as well as the outer diameter D of the tunnel; the abandoned tunnel treatment area 1 is the abandoned tunnel area within 12-18 m on both sides of the tunnel boundary. S2. Along the length of abandoned roadway 2, divide abandoned roadway treatment area 1 into different influence zones according to the L / D value as follows: Areas with an L / D ratio greater than 3 in the abandoned alleyway treatment area are designated as no-impact zones. The area within the abandoned tunnel treatment zone with a length of 1.5 ≤ L / D ≤ 3 is designated as a warning zone; Areas with L / D < 1.5 in the abandoned roadway treatment area are designated as treatment zones; Typically, in actual engineering projects, the treatment area 1 of an abandoned roadway is divided into n no-impact zones, m attention zones, and k control zones; where n, m, and k are integers greater than or equal to 0. For ease of understanding of this invention, an example is provided, such as... Figure 7 As shown, in one project, the treatment area for abandoned tunnels was divided into one attention area and one measure area; for example... Figure 8 As shown, in another project, the treatment area for abandoned tunnels was divided into one no-impact zone, one caution zone, and one measures zone; S3. Before tunnel construction, implement graded dynamic treatment measures for different affected areas: For areas with no impact, it is believed that abandoned tunnels have little impact on tunnel construction and no special treatment is required. For the area of concern, it is believed that the abandoned roadway has a potential impact on the tunnel construction. Before the tunnel construction, conventional backfilling construction is carried out on the abandoned roadway in the area of concern. The conventional backfilling construction specifically involves constructing a retaining wall 10 at one end of the area of concern along the length of the abandoned roadway, and then backfilling the tunnel muck into the area of concern. After that, a retaining wall 10 is constructed at the other end of the area of concern. For the reserve area, before tunnel construction, composite structure support construction is carried out on the abandoned roadways in the reserve area; the composite structure support construction specifically includes: Please see Figure 1-5 Along the length of the abandoned tunnel, sealing walls 4 are constructed sequentially at intervals of 4-6 m within the measure area to divide the measure area into several backfill sections 5. Simultaneously, along the length of the abandoned tunnel, drainage pipes 6 are installed on both sides of the tunnel floor slab within the measure area and wrapped with geotextile. Drainage holes are evenly arranged on the side of the drainage pipes 6 facing the interior of the abandoned tunnel. While constructing each sealing wall 4, tunnel slag 7 is backfilled in layers between each sealing wall 4 under construction and the previous completed sealing wall 4. A pouring space for the sealing top slab is reserved above the tunnel slag 7, and a conveying port 8 is reserved at the top of the sealing wall. Concrete is then poured into the pouring space through the conveying port to form the sealing top slab 9, thereby completing the backfilling construction of the corresponding backfill section. The sealing wall 4 includes two thick end walls 401 located at the outermost end of the measure area and a thin middle wall 402 located between the thick end walls; the thick end walls 401 are made of reinforced concrete and the thickness is controlled to be 180-220 cm; the thin middle wall 402 is made of brick and the thickness is controlled to be 40-60 cm; the sealing top plate 9 is made of C15 concrete and the thickness is 50-70 cm. In addition, when the abandoned roadway treatment area 1 includes adjacent measure areas and attention areas, since the overall elevation of the attention area is lower than that of the measure area, in order to facilitate the transportation of tunnel muck, concrete, bricks and other materials and the backfilling of tunnel muck, the attention area with the lower position should be treated first, and then the measure area with the higher position should be treated. In order to reduce unnecessary construction procedures, when treating the measure area at the adjacent position of the measure area and the attention area, the retaining wall that has been completed in the attention area can be directly used as the thick end wall of the measure area. S4. Tunnel Excavation. The tunnel construction adopts the CRD method for step-by-step excavation. When the abandoned roadway treatment area includes a warning zone, when the tunnel construction reaches the crossing area 11, the settlement rate of the abandoned roadway in the warning zone is monitored in real time, and the tunnel construction is dynamically adjusted according to the settlement rate; the crossing area is the tunnel construction section within 15-20 m on both sides of the boundary of the abandoned roadway. The dynamic adjustment involves reducing the single excavation advance of the tunnel when the settlement rate of the abandoned tunnel exceeds the warning value. For example, the single excavation advance of the CRD method is adjusted from 1 steel frame to 0.5 frames. Micro-differential control blasting technology is adopted to adjust the inter-section detonation delay to be greater than 200ms. At the same time as tunnel excavation, blasting vibration is monitored in real time, and the maximum charge amount per section is adjusted according to the monitoring data (vibration velocity, main frequency) to ensure that the peak value of blasting vibration velocity is controlled within 3 cm / s. Example 2
[0021] This embodiment is a further explanation and optimization of the graded dynamic treatment construction method for tunnels crossing abandoned roadways in Embodiment 1, aiming to provide more detailed technical details or demonstrate the application effect of this method in specific projects.
[0022] A newly constructed highway tunnel (single-bore, two-lane) passes above an abandoned tunnel. The tunnel is 10.25m wide and has an outer diameter D of 16m. It was constructed using the method described in Example 1, involving graded dynamic treatment. Please refer to [link / reference needed]. Figures 1 to 6 It includes the following steps: S1. Through geological survey and measurement, the location of the abandoned tunnel is accurately located. The abandoned tunnel area within 15 m on both sides of the tunnel boundary is designated as abandoned tunnel treatment area 1. Abandoned tunnel treatment area 1 is the area corresponding to chainage K20+280~K20+320.25. The vertical distance L between the top of abandoned tunnel 2 and the bottom of tunnel 3 within abandoned tunnel treatment area 1 and the outer diameter D of the tunnel are calculated. Specifically, the diameter D of the newly built tunnel is 16m, and the vertical distance L varies between 8m and 30m. S2. Along the length of abandoned roadway 2, divide abandoned roadway treatment area 1 into different influence zones according to the L / D value as follows: The area with L / D < 1.5 in the abandoned roadway treatment area, that is, the area with L < 24 m (1.5D), is divided into the treatment area, which corresponds to the chainage K20+280~K20+302; The area within the abandoned roadway treatment zone where 1.5≤L / D≤3, i.e., 24 m (1.5D)≤L≤48m (3D), is designated as a warning zone, corresponding to station numbers K20+302~K20+320.25. S3. Before tunnel construction, implement graded dynamic treatment measures for different affected areas: First, the treatment and construction work for the attention area with chainage K20+302~K20+320.25 is carried out. Specifically, along the length of the abandoned tunnel, a sealing wall is constructed at one end of the attention area. Then, the tunnel slag generated from the highway tunnel excavation is backfilled into the attention area. After that, a sealing wall is constructed at the other end of the attention area. Subsequently, treatment construction was carried out on the treatment area from chainage K20+302 to K20+320.25, specifically as follows: Along the length of the abandoned tunnel, sealing walls 4 were constructed at 4m intervals within the treatment area to divide the area into 5 backfill sections 5; simultaneously, along the length of the abandoned tunnel, Φ160mm HDPE drainage pipes 6 were installed on both sides of the tunnel floor slab within the treatment area and wrapped with 400g / ㎡ geotextile. Drainage holes were evenly distributed on the side of the drainage pipes 6 facing the interior of the abandoned tunnel to draw out any possible groundwater; during the construction of each sealing wall 4, the same... In the next step, tunnel slag 7 is backfilled between the sealing wall 4 under construction and the previous completed sealing wall 4. A pouring space for the sealing top slab is reserved above the tunnel slag 7, and a conveying port 8 is reserved at the top of the sealing wall. Then, concrete is poured into the pouring space through the conveying port to form the sealing top slab 9, thus completing the backfilling construction of the corresponding backfill section. The sealing wall 4 includes two thick end walls 401 located at the outermost end of the measure area and a thin middle wall 402 located between the thick end walls. The thick end walls 401 are cast with reinforced concrete (concrete grade C20) and the thickness is controlled to be 200 cm. The thin middle wall 402 is formed by brick masonry and the thickness is controlled to be 50 cm. The sealing top slab 9 is cast with C15 concrete and the thickness is 50 cm. S4, Tunnel Excavation The tunnel was excavated using the CRD method, with each cycle advance controlled at 0.75 meters (approximately the spacing of one steel frame), and electronic detonators were used for micro-delay blasting. Since the abandoned tunnel treatment area included a warning zone, monitoring points were set up on the top of the warning zone's tunnels when the tunnel construction reached the crossing area to monitor the settlement rate of the abandoned tunnels in real time. Tunnel construction was dynamically adjusted based on the settlement rate. In this embodiment, the crossing area was the tunnel construction section within 18 meters on both sides of the boundary of the abandoned tunnel, specifically the area from chainage K12+202 to K12+242. During construction, monitoring data showed that the settlement rate accelerated, exceeding the set threshold. Therefore, the CRD excavation advance was reduced to 0.4 meters, and the single-stage charge of micro-delay blasting was strictly controlled to ensure that the vibration velocity of the surface and support structure was less than 3 cm / s. After these adjustments, the settlement was effectively controlled.
[0023] Using this method, the project successfully traversed abandoned tunnel areas, with the cumulative surface settlement controlled within 30mm, far below the standard requirements. Compared with the original design of a full-line high-pressure grouting scheme, it saved approximately 35% in costs and shortened the construction period by approximately 15%.
[0024] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.
Claims
1. A graded dynamic treatment construction method for tunnels crossing abandoned roadways, characterized in that, Includes the following steps: S1. Calculate the vertical distance L between the top of the abandoned tunnel and the bottom of the tunnel within the abandoned tunnel treatment area, as well as the outer diameter D of the tunnel. S2. Along the length of the abandoned tunnel, the treatment area is divided into different impact zones according to the L / D value as follows: Areas with an L / D ratio greater than 3 in the abandoned alleyway treatment area are designated as no-impact zones. The area within the abandoned tunnel treatment zone with a length of 1.5 ≤ L / D ≤ 3 is designated as a warning zone; Areas with L / D < 1.5 in the abandoned roadway treatment area are designated as treatment zones; S3. Before tunnel construction, implement graded dynamic treatment measures for different affected areas: No special treatment will be given to areas without impact. The area under attention was backfilled using standard procedures. Composite structure support construction shall be carried out in the measure area; S4, Tunnel excavation.
2. The graded dynamic treatment construction method for tunnels crossing abandoned roadways as described in claim 1, characterized in that, The abandoned tunnel treatment area refers to the abandoned tunnel area within 12-18 m on both sides of the tunnel boundary.
3. The graded dynamic treatment construction method for tunnels crossing abandoned roadways as described in claim 1, characterized in that, The conventional backfilling construction specifically involves constructing a retaining wall at one end of the warning zone along the length of the abandoned tunnel, then backfilling the tunnel slag into the warning zone, and finally constructing a retaining wall at the other end of the warning zone.
4. The graded dynamic treatment construction method for tunnels crossing abandoned roadways as described in claim 1, characterized in that, The construction of the composite structure support is specifically as follows: Along the length of the abandoned tunnel, sealing walls are constructed sequentially at intervals of 4-6 m within the measure area to divide the measure area into several backfill sections; During the construction of each sealing wall, tunnel slag is backfilled in layers between each sealing wall under construction and the previous completed sealing wall. A pouring space for the sealing top slab is reserved above the tunnel slag, and a conveying port is reserved at the top of the sealing wall. Concrete is then poured into the pouring space through the conveying port to form the sealing top slab, thus completing the backfilling construction of the corresponding backfill section.
5. The graded dynamic treatment construction method for tunnels crossing abandoned roadways as described in claim 4, characterized in that, The sealing wall includes two thick end walls located at the outermost end of the measure area and a thin middle wall located between the thick end walls; The thick end wall is formed by casting reinforced concrete, with a thickness controlled at 180-220 cm; the thin middle wall is formed by brick masonry, with a thickness controlled at 40-60 cm.
6. The graded dynamic treatment construction method for tunnels crossing abandoned roadways as described in claim 4, characterized in that, The sealing top plate is made of C15 concrete with a thickness of 50-70 cm.
7. The graded dynamic treatment construction method for tunnels crossing abandoned roadways as described in claim 4, characterized in that, It also includes installing drainage pipes along the length of the abandoned tunnel at both corners of the tunnel floor slab within the protection zone and wrapping them with geotextile fabric, with drainage holes evenly distributed on the side of the drainage pipe facing the interior of the abandoned tunnel.
8. The graded dynamic treatment construction method for tunnels crossing abandoned roadways as described in claim 1, characterized in that, In step S4, when the abandoned roadway treatment area includes a warning area, the settlement rate of the abandoned roadway in the warning area is monitored in real time when the tunnel construction reaches the crossing area, and the tunnel construction is dynamically adjusted according to the settlement rate.
9. A graded dynamic treatment construction method for tunnels crossing abandoned roadways as described in claim 8, characterized in that, The crossing area refers to the tunnel construction section within 15-20 m on both sides of the boundary of the abandoned tunnel.
10. A graded dynamic treatment construction method for tunnels crossing abandoned roadways as described in claim 8, characterized in that, The dynamic adjustment involves reducing the single excavation advance of the tunnel and using micro-differential controlled blasting technology when the settlement rate exceeds the warning value, thereby controlling the peak blasting vibration velocity to within 3 cm / s.