Stratum reinforcement method for underpass tunnel non-stop construction in airport flying area

Abstract

The invention belongs to the technical field of stratum reinforcement treatment, and provides a stratum reinforcement method for underpass tunnel non-stop construction in an airport flying area, which comprises the following steps of: designing a line flat vertical section scheme of a preceding small-diameter shield tunnel and a lining segment of the preceding small-diameter shield tunnel according to the existing exploration drilling data of an airport runway; a small-diameter shield tunnel is constructed in advance, a pipe shed guide pipe punching hole is reserved in the lining segment, and a check valve device is installed at the position of the pipe shed guide pipe punching hole; an operation platform is arranged in the advanced small-diameter shield tunnel; according to the reinforcing technical scheme, construction of the pipe shed guide pipe is completed; and through the operation platform, stratum grouting reinforcement is conducted through the pipe shed guide pipe. According to the method, the existing exploration drilling data of the airport runway in advance are utilized, the advance small-diameter shield tunnel is implemented, and the stratum reinforcement operation is implemented in the advance small-diameter shield tunnel, so that the non-stop construction of the airport flying area is realized, and the influence on the normal operation of the airport is effectively reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of formation reinforcement treatment, and particularly relates to a method for reinforcing the formation during non-stop construction of an underpass tunnel in the airport flight area. Background Art

[0002] With the rapid development of the aviation industry, the demand for air transportation continues to grow, and the expansion and renovation projects of airport flight areas are increasing day by day. Among them, the construction of underpass channels inside the airport flight area is a key measure to improve the overall service level of the airport and ensure operational safety, and has become a necessary condition to support the long-term development of the airport. The construction of underpass tunnels inside the airport flight area often needs to cross existing runways, taxiways or other important facilities. Given that the airport flight area is a region where aircraft take off and land frequently, with large aircraft takeoff and landing loads and high environmental sensitivity, extremely strict requirements are put forward for settlement control and construction safety.

[0003] Due to the particularity of air transportation and the increasing busyness of airport transportation with the development of the aviation industry, especially for international airports, the possibility of implementing construction during a flight suspension is extremely low. Most construction activities in the flight area adopt the method of non-stop construction. Considering the flight principle of aircraft, engineering construction activities in the flight area mainly affect the height limit of the flight area and the flatness of the runway. Therefore, to achieve non-stop construction, it is mainly necessary to meet the requirements of air defense safety and runway operation safety, that is, to meet the requirements of flight area obstacle restrictions and runway settlement. During the actual engineering implementation, due to poor formation conditions, formation reinforcement measures often need to be taken to ensure that the runway settlement meets the settlement control requirements of the airport pavement area. Therefore, how to achieve formation reinforcement during non-stop construction of the airport flight area is an urgent problem to be solved. Summary of the Invention

[0004] In order to solve the above existing problems, the present invention designs a method for reinforcing the formation during non-stop construction of an underpass tunnel in the airport flight area. The specific technical solutions are as follows:

[0005] A method for reinforcing the formation during non-stop construction of an underpass tunnel in the airport flight area includes the following specific steps:

[0006] S1. According to the existing exploration borehole data of the airport runway, design the line horizontal and vertical section plan of the pilot small-diameter shield tunnel and the lining segments of the pilot small-diameter shield tunnel, and implement the pilot small-diameter shield tunnel. Pipe shed guide pipe punching holes are reserved on the lining segments, and check valve devices are installed at the pipe shed guide pipe punching holes;

[0007] S2. Set up an operation platform in the pilot small-diameter shield tunnel. The operation platform can move along the tunnel length direction in the small-diameter shield tunnel and can adjust its height;

[0008] S3. Determine the driving position, driving angle, and driving length of the pipe shed guide pipe according to the reinforcement technical solution, and complete the driving construction of the pipe shed guide pipe. The pipe shed guide pipe is made of seamless steel pipe, installed in sections, and the two sections are connected by sleeve welding or screw rod connection. The grouting holes are arranged on the seamless steel pipe according to the specifications.

[0009] S4. Through the operation platform, conduct stratum grouting reinforcement through the pipe shed guide pipe. The water-cement ratio of the grouting slurry is 0.5:1 to 1:1, and the grouting pressure is 0.2 to 1.0 MPa.

[0010] In a preferred implementation manner, the method for designing the line profile plan of the advanced small-diameter shield tunnel includes the following steps:

[0011] According to the requirements of the stratum reinforcement range, determine the driving plan of the pipe shed guide pipe and the operation space requirements, and draw up the diameter of the advanced small-diameter shield tunnel.

[0012] Based on the existing exploration borehole data of the airport runway, clarify the geological and hydrological conditions in the shallow layer below, and combine with the designed line of the to-be-built underpass tunnel to design and optimize the line profile plan of the advanced small-diameter shield tunnel.

[0013] In a preferred implementation manner, the method for designing the lining segments of the advanced small-diameter shield tunnel is as follows:

[0014] According to the line and contour of the advanced small-diameter shield tunnel, use the existing exploration borehole data to design the thickness, number of segments, and reinforcement of the lining segments of the advanced small-diameter shield tunnel to meet the bearing capacity, stiffness, and use requirements.

[0015] In a preferred implementation manner, a horizontal inclinometer is used to monitor the deflection angle in real time during the driving process of the pipe shed guide pipe. When the value of the deflection angle exceeds the allowable range, corrective work is carried out in a timely manner.

[0016] In a preferred implementation manner, the grouting reinforcement is carried out by grouting in alternate holes, and the subsequent grouting holes are constructed after the grouting strength of the adjacent grouting holes reaches the standard, so as to control and reduce the settlement generated during the construction period.

[0017] In a preferred implementation manner, when implementing the advanced small-diameter shield tunnel, at least the following specific steps need to be satisfied:

[0018] Before construction, conduct a detailed investigation of the design and completion data of the airport's previous projects and the underground pipeline data;

[0019] During the construction process, ensure the accurate assembly position of the tunnel segments to reduce the subsequent manual drilling;

[0020] During the construction process, construction monitoring is carried out, and information feedback is used to control the shield construction parameters. Synchronous grouting and secondary grouting are carried out in a timely manner to control the settlement of the pavement area to meet 40% of the limit value required for airport operation.

[0021] The construction of the small-diameter shield tunnel passing through the airport pavement area is divided into a test section, a crossing section, and a protection section. The length of the test section is 45m - 55m, which is used to determine the parameters of the shield tunnel passing through the airport pavement area and ensure the settlement control of the shield tunnel passing through the airport pavement area. The length of the protection section is 25m - 35m, which is used to strengthen the control of shield construction parameters. The length of the crossing section is determined according to the actual construction scope.

[0022] In a preferred implementation manner, the construction monitoring adopts a combination of automated monitoring and manual monitoring, specifically including:

[0023] For the automated monitoring, reflective sheets are arranged in advance in the pavement area, and a total station is used to automatically scan the measurement area without a prism. The settlement monitoring data value of the pavement area is obtained by comparing the change amount of the measurement data during construction with the initial measurement data.

[0024] For the manual monitoring, manual monitoring sections are arranged in the direction of the axis and the vertical axis of the small-diameter shield tunnel, and manual monitoring is carried out after the airport stops operating every day.

[0025] After the airport stops operating every day, the data of the automated monitoring and the data of the manual monitoring are cross-checked with each other to ensure the accuracy of the monitoring data.

[0026] In a preferred implementation manner, the limit requirements for the monitoring data are that the height difference within 3 meters of the cement concrete pavement is less than or equal to 10mm, the joint offset of the slab is less than or equal to 5mm, and the total settlement of the joint offset of the slab is less than or equal to 30mm. The differential settlement rate of the airport runway is less than or equal to 1‰, and the differential rate of the airport taxiway is less than or equal to 1.5‰.

[0027] In a preferred implementation manner, S3. After determining the driving position, driving angle, and driving length of the pipe shed guide pipe according to the reinforcement technical plan, check whether the position and quantity of the reserved pipe shed guide pipe driving holes on the lining segment meet the requirements. If not, drill holes on site according to the actual plan, and the position of the drill holes should avoid the position of the stress reinforcement bars of the lining segment.

[0028] Compared with the prior art, the beneficial effects of the present invention are:

[0029] 1) The present invention utilizes the existing exploration borehole data of the airport runway in advance, implements a small-diameter shield tunnel first, and carries out stratum reinforcement operations in the small-diameter shield tunnel first, realizing non-stop construction in the airport flight area and effectively reducing the impact on the normal operation of the airport.

[0030] 2) The present invention provides a practical reinforcement technology for the airport flight zone underpass tunnel, solves the problem of airport flight zone stratum reinforcement, and ensures the feasibility of the airport flight zone underpass tunnel project.

[0031] 3) The present invention avoids the problem of damage to the airport pavement area caused by ground operations in the airport flight zone and ground reinforcement technology, overcomes the problems of pavement area repair and runway go-around inspection procedures, and reduces the management work of personnel entering and leaving the flight zone. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0033] Figure 1 The present invention is a flow chart of a method for reinforcing the ground under a tunnel in an airport flight zone without stopping flights according to an embodiment of the present invention.

[0034] Figure 2 It is a structural schematic diagram of on-site construction of an embodiment of the present invention.

[0035] In the figure: 1. Preliminary small-diameter shield tunnel; 2. Working platform; 3. Underpass tunnel to be built; 4. Pipe shelf guide pipe. DETAILED DESCRIPTION

[0036] The present invention is further illustrated below through the description of specific implementation methods, but this is not a limitation of the present invention. Those skilled in the art can make various modifications or improvements based on the basic idea of ​​the present invention, but as long as they do not deviate from the basic idea of ​​the present invention, they are all within the protection scope of the present invention.

[0037] See also Figure 1 , an embodiment provided by the present invention is as follows:

[0038] S1. Based on the existing survey and drilling data of the airport runway, the plan of the horizontal and vertical sections of the route of the first small-diameter shield tunnel 1 and the lining segments of the first small-diameter shield tunnel 1 are designed, and the first small-diameter shield tunnel 1 is implemented. The lining segments are provided with holes for the pipe shed guide pipe 4, and a check valve device is installed at the holes for the pipe shed guide pipe 4;

[0039] In this embodiment, the leading small-diameter shield tunnel 1 is arranged in the middle of the construction area of ​​the underpass tunnel 3 to be built. The diameter of the leading small-diameter shield tunnel 1 is between 4m and 6m. The burial depth of the leading small-diameter shield tunnel 1 is not less than one times the diameter of the leading small-diameter shield tunnel 1, and the burial depth of the bottom of the leading small-diameter shield tunnel 1 from the bottom of the existing survey borehole is not less than one times the diameter of the leading small-diameter shield tunnel 1. The starting receiving well of the leading small-diameter shield tunnel 1 is combined with the working well of the underpass tunnel 3 to be built.

[0040] Specifically, the route horizontal and vertical alignment plan of the design-leading small-diameter shield tunnel 1 includes the following steps:

[0041] According to the requirements of the stratum reinforcement range, determine the driving plan of the pipe shed guide pipe 4 and the operation space requirements, and formulate the diameter of the leading small-diameter shield tunnel 1.

[0042] Based on the existing exploration borehole data of the airport runway, clarify the geological and hydrological conditions in the shallow area below, and combine with the design route of the to-be-built undercrossing tunnel 3 to design and optimize the route horizontal and vertical alignment plan of the leading small-diameter shield tunnel 1.

[0043] Specifically, the method for lining segments of the design-leading small-diameter shield tunnel 1 is as follows:

[0044] According to the route and contour of the leading small-diameter shield tunnel 1, using the existing exploration borehole data, design the thickness, number of segments, and reinforcement of the lining segments of the leading small-diameter shield tunnel 1 to meet the bearing capacity, stiffness, and service requirements.

[0045] In this embodiment, when implementing the leading small-diameter shield tunnel 1, at least the following specific steps need to be satisfied:

[0046] Before construction, conduct a detailed investigation of the preliminary engineering design and completion data of the airport and the underground pipeline data.

[0047] During the construction process, ensure the accurate assembly position of the tunnel segments to reduce the later manual drilling.

[0048] During the construction process, carry out construction monitoring, feedback the construction information, control the shield construction parameters, and conduct synchronous grouting and secondary grouting in a timely manner to control the settlement in the pavement area to meet 40% of the limit value required for airport operation.

[0049] Divide the construction of the leading small-diameter shield tunnel 1 passing through the airport pavement area into a test section, a crossing section, and a protection section. The length of the test section is 45m - 55m, which is used to determine the parameters for the shield tunnel to pass through the airport pavement area and ensure the settlement control of the shield tunnel passing through the airport pavement area. The length of the protection section is 25m - 35m, which is used to strengthen the control of the shield construction parameters. The length of the crossing section is determined according to the actual construction scope.

[0050] Specifically, the construction monitoring adopts a combination of automated monitoring and manual monitoring, which specifically includes:

[0051] The automated monitoring is to arrange reflective sheets in advance in the pavement area, use a total station to automatically scan the measurement area without a prism, and obtain the settlement monitoring data value of the pavement area by comparing the change amount of the measurement data during construction with the initial measurement data.

[0052] The manual monitoring is to arrange manual monitoring sections in the axial direction and the vertical axial direction of the small-diameter shield tunnel, and the manual monitoring is carried out after the airport stops operating every day;

[0053] After the airport stops operating every day, the data of the automated monitoring and the data of the manual monitoring are cross-checked with each other to ensure the accuracy of the monitoring data.

[0054] The limit requirements for the monitoring data are that the height difference within 3 meters of the cement concrete pavement is less than or equal to 10 mm, the joint offset of the slab is less than or equal to 5 mm, and the total settlement of the joint offset of the slab is less than or equal to 30 mm, the differential settlement rate of the airport runway is less than or equal to 1‰, and the differential rate of the airport taxiway is less than or equal to 1.5‰.

[0055] S2. A working platform 2 is arranged in the prior small-diameter shield tunnel 1. The working platform 2 can move along the tunnel length direction in the small-diameter shield tunnel and can adjust its height.

[0056] S3. According to the reinforcement technical scheme, determine the driving position, driving angle and driving length of the pipe roof guide pipe 4, and complete the driving construction of the pipe roof guide pipe 4. The pipe roof guide pipe 4 is made of seamless steel pipe, which is installed in sections, and the two sections are connected by sleeve welding or screw rod connection. The grouting holes are arranged on the seamless steel pipe according to the specifications.

[0057] In a preferred implementation manner, after S3. According to the reinforcement technical scheme, determine the driving position, driving angle and driving length of the pipe roof guide pipe 4, check whether the positions and quantities of the reserved holes for driving the pipe roof guide pipe 4 on the lining segments meet the requirements. If not, drill holes on site according to the actual scheme, and the positions of the drilled holes avoid the positions of the stress bars of the lining segments.

[0058] In this embodiment, during the driving process of the pipe roof guide pipe 4, a horizontal inclinometer is used to monitor the inclination degree in real time. When the value of the inclination degree exceeds the allowable range, the deviation correction work is carried out in time.

[0059] S4. Through the working platform 2, the formation grouting reinforcement is carried out through the pipe roof guide pipe 4. The water-cement ratio of the grouting slurry is 0.5:1 to 1:1, and the grouting pressure is 0.2 to 1.0 MPa.

[0060] It should be noted that the grouting pressure during pipe roof grouting cannot be too large. The grouting effect should be checked at appropriate positions, and according to the inspection results, the construction parameters such as the grouting pressure are adjusted.

[0061] The grouting reinforcement adopts hole-by-hole grouting, and the subsequent grouting holes are constructed after the grouting strength of the adjacent grouting holes reaches the standard, so as to control and reduce the settlement generated during the construction.

[0062] The above embodiments are only illustrative of the principles and effects of the present invention and are not intended to limit the present invention. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical idea disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. A method for strengthening the ground for the construction of a tunnel under an airport flight area without stopping flights, characterized in that: The specific steps include: S1. Based on the existing survey and drilling data of the airport runway, design the route horizontal and vertical section scheme of the advance small-diameter shield tunnel and the lining segments of the advance small-diameter shield tunnel, and implement the advance small-diameter shield tunnel. The lining segments are provided with holes for drilling the pipe shed guide pipes, and a check valve device is installed at the holes for drilling the pipe shed guide pipes; S2. Setting a working platform in the preceding small-diameter shield tunnel, wherein the working platform can move along the length direction of the tunnel in the small-diameter shield tunnel and can adjust the height; S3. According to the reinforcement technical plan, determine the installation position, installation angle and installation length of the pipe-roof guide pipe, and complete the installation of the pipe-roof guide pipe. The pipe-roof guide pipe is made of seamless steel pipe, which is installed in sections. The two sections are connected by casing welding or screw rods. Grouting holes are arranged on the seamless steel pipe according to the specifications. S4. Through the working platform, grouting reinforcement is performed on the stratum through the pipe-roof guide pipe, the water-cement ratio of the grouting slurry is 0.5:1 to 1:1, and the grouting pressure is 0.2 to 1.0 MPa.

2. The method for strengthening the ground for the non-stop flight construction under the tunnel of the airport flight zone according to claim 1 is characterized in that: The plan for designing the horizontal and vertical sections of the route of the first small-diameter shield tunnel includes the following steps: According to the requirements of the ground reinforcement scope, determine the pipe-roof guide pipe installation plan and working space requirements, and plan the diameter of the first small-diameter shield tunnel; Based on the existing survey and drilling data of the airport runway, the geological and hydrological conditions of the shallow area below are clarified, and combined with the design route of the underpass to be built, the horizontal and vertical section plan of the route of the first small-diameter shield tunnel is designed and optimized.

3. The method for strengthening the ground for the non-stop flight construction under the tunnel of the airport flight zone according to claim 1 is characterized in that: The method for designing the lining segments of the first small-diameter shield tunnel is: According to the route and contour of the preceding small-diameter shield tunnel and using the existing survey drilling data, the thickness, number of blocks and reinforcement of the lining segments of the preceding small-diameter shield tunnel are designed to meet the bearing capacity, stiffness and usage requirements.

4. The method for strengthening the ground for the non-stop flight construction under the tunnel of the airport flight zone according to claim 1 is characterized in that: During the installation and drilling process of the guide pipe of the pipe rack, a horizontal inclinometer is used to monitor the deflection in real time. When the deflection value exceeds the allowable range, correction work is carried out in time.

5. The method for strengthening the ground for the non-stop flight construction under the tunnel of the airport flight zone according to claim 1 is characterized in that: The grouting reinforcement adopts grouting in alternate holes, and subsequent grouting holes are constructed after the grouting strength of adjacent grouting holes reaches the standard, so as to control and reduce the settlement generated during the construction.

6. The method for strengthening the ground for the non-stop flight construction under the tunnel of the airport flight zone according to claim 1 is characterized in that: When implementing the aforementioned small-diameter shield tunnel, at least the following specific steps need to be met: Before construction, conduct a detailed investigation of the airport's preliminary engineering design and completion data, as well as underground pipeline data; Ensure accurate assembly points of tunnel segments during construction to reduce manual drilling in the later stages; During the construction process, construction monitoring is carried out, information-based feedback is provided for construction, shield construction parameters are controlled, synchronous grouting and secondary grouting are carried out in a timely manner, and the settlement of the pavement area is controlled to meet the airport operation requirement limit of 40%; The construction of the first small-diameter shield tunnel crossing the airport pavement area is divided into a test section, a crossing section and a protection section. The test section is 45m to 55m long and is used to determine the parameters of the shield tunnel crossing the airport pavement area to ensure the settlement control of the shield tunnel crossing the airport pavement area. The protection section is 25m to 35m long and is used to strengthen the control of shield construction parameters. The length of the crossing section is determined according to the actual construction scope.

7. The method for strengthening the ground for the non-stop flight construction under the tunnel of the airport flight zone according to claim 6 is characterized in that: The construction monitoring adopts a combination of automatic monitoring and manual monitoring, which specifically includes: The automatic monitoring is to arrange reflective sheets in advance in the road surface area, use a total station to automatically scan the measurement area without a prism, and obtain the settlement monitoring data value of the surface area by comparing the measurement data during construction with the change in the initial measurement data; The manual monitoring is to arrange manual monitoring sections in the axis and vertical axis direction of the small diameter shield tunnel, and conduct manual monitoring after the airport stops flying every day; After the airport stops flying every day, the data from the automated monitoring is cross-checked with the data from the manual monitoring to ensure the accuracy of the monitoring data.

8. The method for strengthening the ground for the construction of the tunnel under the airport flight area without stopping flights according to claim 7 is characterized in that: The limit requirements for the monitoring data are that the height difference within 3 meters of the cement concrete pavement is less than or equal to 10mm, the slab joint misalignment is less than or equal to 5mm, and the total settlement of the slab joint misalignment is less than or equal to 30mm, the differential settlement rate of the airport runway is less than or equal to 1‰, and the differential rate of the airport taxiway is less than or equal to 1.5‰.

9. The method for strengthening the ground for the non-stop flight construction under the tunnel of the airport flight zone according to claim 1 is characterized in that: S3. After determining the location, angle and length of the pipe-roof guide pipe according to the reinforcement technical plan, check whether the location and number of the reserved holes for the pipe-roof guide pipe on the lining segment meet the requirements. If not, drill holes on site according to the actual plan, and avoid the location of the stress-bearing steel bars of the lining segment.

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