Construction method for installing super-long horizontal storage tank in mountain circular tunnel

Abstract

The construction method for installing the ultra-long horizontal storage tank in the mountain circular tunnel comprises the following steps that firstly, excavation and primary supporting are conducted on the mountain circular tunnel, then an inverted arch face of a secondary lining is constructed in the tunnel, the inverted arch face is constructed according to preset segments, and the inverted arch face is constructed according to the preset segments; the longitudinal highest point is located below the center line of the tunnel, and a track fixing component and a grouting pipeline are pre-buried; 2, after concrete of the inverted arch face of the secondary lining reaches the design strength index, roughening treatment is conducted on the arc-shaped surface of the inner side face of the inverted arch face, and the bonding strength of the contact face of new concrete and old concrete is enhanced; meanwhile, a sliding rail is arranged in the middle of the inverted arch vertical wall of the secondary lining; and thirdly, the storage tank is divided into a plurality of sections, and it is ensured that the tail of each section extends out of the corresponding secondary lining inverted arch section by at least one meter. According to the method, the technical problem that the ultra-long horizontal storage tank is installed in the mountain circular tunnel is solved, and remarkable progress is made in the aspects of construction efficiency, safety, structural performance and the like.

Description

Technical Field

[0001] The invention relates to the technical field of building engineering construction, and in particular to a construction method for installing an extra-long horizontal storage tank in a circular tunnel in a mountain. Background Art

[0002] The storage tank in the mountain tunnel relies on the mountain to bear the pressure, and the pressure in the storage tank needs to be reliably transmitted to the mountain. The concrete lining interlayer between the storage tank and the mountain must be uniform and reliable. However, due to the excessive length and width of the storage tank, it is difficult to enter the cave due to the narrow space; after the storage tank enters the cave, the construction surface between the storage tank and the mountain is narrow, and it is difficult for operators to carry out concrete operations. In addition, the storage tank is too long, the concrete transportation is difficult, the pouring distance is long, and the vibration is difficult, which easily leads to the situation that the concrete is not poured in place and the vibration is insufficient. For example, the storage tank section of a certain project is 45m long and 5600mm in diameter. The construction content is divided into the initial support layer: circular 100mm thick UHPC shotcrete; secondary lining layer: circular 700mm thick UHPC reinforced concrete; steel storage tank: 45m long, Ф4000mm steel storage tank. As the distance between the storage tank and the initial support is only 700mm and the length is 45m, the conventional method of pouring the secondary lining layer after the storage tank is put in as a whole requires laying a horizontal passage in advance, and the circular opening needs to be changed to a circular arch; the overall length of the tunnel is 45m, and it is difficult to ensure the pouring density when pouring concrete over a long distance, and the construction space is only 700mm, which is difficult to use for concrete construction. Summary of the invention

[0003] The purpose of the present invention is to provide a construction method for installing an extra-long horizontal storage tank in a circular tunnel in a mountain, in view of the shortcomings of the prior art.

[0004] The specific technical solutions are as follows:

[0005] A construction method for installing an extra-long horizontal storage tank in a circular tunnel in a mountain, comprising the following steps:

[0006] Step 1: excavate and initially support the mountain circular tunnel, then construct a secondary lining inverted arch surface inside the tunnel, the inverted arch surface is constructed in predetermined sections, the longitudinal highest point of which is located below the center line of the tunnel, and track fixing components and grouting pipes are pre-buried during the construction process;

[0007] Step 2: When the concrete of the secondary lining arch surface reaches the design strength index, the arc surface of the inner side is roughened to strengthen the bonding strength of the contact surface between the new and old concrete; at the same time, a slide rail is set in the middle of the secondary lining arch wall;

[0008] Step 3: Design and manufacture the storage tank, divide the storage tank into several sections, and ensure that the tail of each section extends at least 1 meter beyond the corresponding secondary lining arch section as the welding preparation area for adjacent sections; install the anti-floating device and the sliding support device in the central part of the outside of the storage tank;

[0009] Step 4: Use a trackless ground-level mobile vehicle to load the tank segment, and use a hydraulic crawler and a hydraulic jack provided on the invert surface of the secondary lining to push the tank to the predetermined position;

[0010] Step 4: After the initial positioning of the tank segment is completed, the anti-floating device is lifted with the help of a jack, and the sliding support device is removed to place the tank segment securely on the invert surface; then all temporary auxiliary facilities are removed and the tank segment is locked;

[0011] Step 5: Use steel formwork to cover the top gap between the tank segment and the initial support, and perform concrete pouring in this area; when the concrete hardens to the specified level, inject pressurized cement slurry through the pre-installed grouting pipe to seal the gap between the tank and the lining;

[0012] Step 6. Repeat steps 3 to 5 until all tank segments are installed to form a complete and continuous extra-long horizontal tank.

[0013] Optionally, the segmented construction of the secondary lining is carried out synchronously and staggered with the installation of the tank segments to provide necessary concrete pouring operation space and ensure the quality of concrete pouring and the density of the structure.

[0014] Optionally, self-compacting high-strength grouting material is used to fill the gaps between the crown arch and the primary support, and between the tank and the secondary lining.

[0015] Optionally, the trackless ground moving vehicle is equipped with an arc-shaped support for supporting the tank segment.

[0016] Optionally, the segment length of the tank segment is designed to be 8-12 meters to facilitate flexible transportation and installation in the tunnel.

[0017] Optionally, the anti-floating device includes an anti-floating plate, and the anti-floating plate is located on the upper part of the inverted arch wall of the secondary lining.

[0018] Optionally, the sliding support device includes a sliding shoe, the bottom of which is equipped with a roller, and the roller is slidably connected to the slide rail.

[0019] Optionally, at least two sets of anti-floating devices and sliding support devices are provided in the upper county of each section of the storage tank.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] The method of the present invention divides the storage tank into several small sections that are easy to carry and install, and combines the segmented construction strategy of the tunnel secondary lining, which not only ensures the transportation flexibility of the storage tank, but also simplifies the on-site installation process, and improves the construction efficiency and safety; and uses the anti-floating device, the sliding support device and the pre-buried track on the tunnel invert surface to form a multi-level support and guidance mechanism, effectively controlling the movement trajectory of the storage tank, and ensuring the stability and accuracy of the storage tank in the process of positioning; in addition, by roughening the secondary lining invert surface, the bonding force between the new and old concrete is enhanced, and the integrity of the structure is improved. At the same time, the high-pressure grouting process is used to fill the gap between the storage tank and the lining, which not only enhances the sealing performance, but also makes up for the small errors in the construction process, ensuring the long-term stability and waterproof performance of the storage tank; using modern mechanical equipment such as trackless ground-level mobile vehicles, hydraulic crawlers and jacks, it greatly reduces the burden of manpower, improves the level of construction automation, shortens the construction period, and reduces construction risks. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of the invert operation in the cave of the present invention;

[0023] Figure 2 This is a schematic diagram of the in-hole storage tank section of the present invention;

[0024] Figure 3 This is a completed diagram of the initial storage tank construction in the cave of the present invention;

[0025] Figure 4 This is a schematic diagram of the construction operation of adjacent sections of storage tanks in a cave of the present invention;

[0026] Figure 5 It is a schematic diagram of the welding space of adjacent storage tanks in the cave of the present invention.

[0027] In the figure: 1. Tunnel; 2. Inverted arch surface; 3. Slide rail; 4. Storage tank; 5. Anti-floating device; 6. Sliding support device; 7. Trackless ground surface moving vehicle; 8. Hydraulic crawler; 9. Hydraulic jack; 10. Arc support; 11. Top arch surface. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0030] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, but they are not intended to limit the present invention.

[0031] The construction method for installing an ultra-long horizontal storage tank in a mountain circular tunnel provided in the present invention is as follows: Figure 1-Figure 5 , including the following steps:

[0032] Step 1: excavate and initially support the mountain circular tunnel 1, then construct the secondary lining inverted arch surface 2 inside the tunnel 1. The inverted arch surface 2 is constructed in sections with a transverse length of 6-10m, and its longitudinal highest point is located 300mm below the center line of the tunnel 1 (to facilitate the placement of the storage tank 4). During the construction process, track fixing components and grouting pipes are pre-buried;

[0033] Step 2: When the concrete of the secondary lining arch surface 2 reaches the design strength index, the arc surface of the inner side is roughened to a depth of ≥50mm to ensure the thickness of the concrete protective layer and strengthen the bonding strength of the contact surface between the new and old concrete; at the same time, a slide rail 3 (43Kg steel rail is to be used) is set in the middle of the secondary lining arch wall;

[0034] Step 3: Design and manufacture the storage tank 4, divide the storage tank 4 into several segments, ensure that the tail of each segment extends at least 1 meter beyond the corresponding secondary lining arch segment, as a welding preparation area for adjacent segments; install an anti-floating device 5 and a sliding support device 6 at the central part of the outside of the storage tank 4;

[0035] Step 4: Use a trackless ground-level mobile vehicle 7 to load the storage tank 4 segment, and use the hydraulic crawler 8 and hydraulic jack 9 provided on the invert surface 2 of the secondary lining to push the storage tank 4 to the predetermined position;

[0036] Step 4: After the initial positioning of the storage tank 4 segments is completed, the anti-floating device 5 is lifted with the help of four jacks, and the sliding support device 6 is removed, so that the storage tank 4 segments are securely placed on the inverted arch surface 2; then all temporary auxiliary facilities are removed and the storage tank 4 segments are locked;

[0037] Step 5: Use steel formwork to cover the top arch space between the storage tank 4 segment and the initial support and reserve a grouting pipe on the top arch surface 11, and perform concrete pouring in this area; when the concrete hardens to a specified level, inject pressurized cement slurry through the pre-set grouting pipe to seal the gap between the storage tank 4 and the lining;

[0038] Step 6: Repeat steps 3 to 5 until all the sections of the storage tank 4 are installed to form a complete and continuous extra-long horizontal storage tank 4.

[0039] The method divides the storage tank 4 into several small sections that are easy to carry and install, and combines the segmented construction strategy of the secondary lining of the tunnel 1, which not only ensures the transportation flexibility of the storage tank 4, but also simplifies the on-site installation process, and improves the construction efficiency and safety; and uses the anti-floating device 5, the sliding support device 6 and the pre-buried track on the inverted arch surface 2 of the tunnel 1 to form a multi-level support and guidance mechanism, effectively controlling the movement trajectory of the storage tank 4, and ensuring the stability and accuracy of the storage tank 4 during the installation process; In addition, by roughening the inverted arch surface 2 of the secondary lining, the bonding force between the new and old concrete is enhanced, and the integrity of the structure is improved. At the same time, the high-pressure grouting process is used to fill the gap between the storage tank 4 and the lining, which not only strengthens the sealing performance, but also makes up for the minor errors in the construction process, ensuring the long-term stability and waterproof performance of the storage tank 4; using modern mechanical equipment such as trackless ground-level mobile vehicles 7, hydraulic crawlers 8 and jacks, it greatly reduces the burden of manpower, improves the level of construction automation, shortens the construction period, and reduces construction risks. Therefore, the method of the present invention not only solves the technical problem of installing an extra-long horizontal storage tank 4 in a mountain circular tunnel 1, but also achieves significant progress in construction efficiency, safety, structural performance, etc.

[0040] In step 4, refer to Figure 2 The trackless ground level moving vehicle 7 uses a trackless ground level vehicle. This platform has strong carrying capacity and mobility, and is suitable for the non-standard ground conditions in the tunnel 1. The trackless ground level vehicle slowly moves to the secondary lining arch section on the pre-laid trestle, and after aligning the center of the tank body, slowly inserts the tank 4 into the arch surface 2; after the limit distance is inserted, the front anti-floating device 5 and the sliding support device 6 of the tank 4 are already overlapped on the arch surface 2 track, forming a primary guide and support foundation. After the hydraulic crawler 8 is installed at the position of the front anti-floating device 5 on the secondary lining inverted arch section, the rear anti-floating device 5 is lifted up by the hydraulic jack 9, the trackless flat car retreats a distance, and then the hydraulic jack 9 is retracted, and the storage tank 4 falls back to the trackless flat car again; the hydraulic crawler 8 and the trackless flat car continue to push the storage tank 4 section until the rear anti-floating device 5 and the sliding support device 6 are on the track of the inverted arch surface 2, and the trackless flat car is completely withdrawn, and finally only the hydraulic crawler 8 is used to push the storage tank 4 to the designated installation position. The efficient cooperation of the trackless flat car and the hydraulic equipment in this method greatly shortens the transportation time and the positioning cycle of the storage tank 4 segment, and also ensures the accuracy of the storage tank 4 during the installation process, reducing the extra adjustment time and labor consumption caused by inaccurate positioning.

[0041] In this embodiment, refer to Figure 3-Figure 5, based on the actual specifications of the tank 4 segment and the space limitations of tunnel 1, the secondary lining is designed as a segmented mode, and the length of each segment strictly matches the width of the tank 4 segment to be installed. This dynamic matching not only saves construction time, but also creates ample operating space for subsequent concrete pouring; the cross-construction method of "tunnel first, then tank" is adopted, that is, a certain length of secondary lining is completed first, followed by the installation of the corresponding length of tank 4 segment, and then the next stage of secondary lining construction is carried out, and this cycle is repeated until the entire tank 4 is installed. This mode effectively avoids construction conflicts and ensures that each link has enough space and time to execute, especially the critical concrete pouring operation. Thanks to the orderly connection between the segmented construction and the installation of tank 4, each concrete pouring is carried out in a relatively independent and undisturbed environment, which is conducive to controlling the fluidity and density of concrete, reducing the generation of bubbles and cracks, and thus improving the integrity and durability of the structure.

[0042] Specifically, the present invention uses self-compacting high-strength grouting material to fill the gaps between the top arch and the initial support, and between the storage tank 4 and the secondary lining. The selected self-compacting high-strength grouting material has the characteristics of good fluidity, high strength and low shrinkage. These characteristics enable the grouting material to flow and fill gaps of any shape on its own, and the ideal density can be achieved without vibration. At the same time, the high-strength property ensures that the filler can withstand external loads and maintain structural stability. The grouting operation needs to be carried out under specific conditions, including but not limited to the selection of temperature, humidity and grouting pressure. Reasonable construction parameter setting can maximize the performance of the grouting material, ensure that the air is completely removed during the grouting process, and prevent the formation of voids or weak areas, thereby improving the integrity and durability of the structure.

[0043] In this embodiment, refer to Figure 2 The trackless ground level mobile vehicle 7 is equipped with an arc support 10 for supporting the segment of the storage tank 4. The curvature of the arc support 10 matches the outer wall of the storage tank 4 to form a point-to-surface contact mode, which can not only disperse the load to the greatest extent and reduce local stress concentration, but also keep the storage tank 4 stable during the entire transportation process to avoid the risk of rolling or overturning.

[0044] Specifically, refer to Figure 3-Figure 5, due to the limited space size of the mountain circular tunnel 1, it is difficult to directly transport the overlong tank 4 segment into the tunnel 1. Therefore, the tank 4 is divided into shorter segments to facilitate passing through the entrance of the tunnel 1 and flexibly move inside the tunnel 1, ensuring the feasibility of the entire installation process; the segment length of the tank 4 segment is designed to be 8-12 meters, and the segment length of 8-12 meters takes into account the capacity requirements of the tank 4 and the transportation conditions of the tunnel 1. A longer single segment can increase the storage capacity of the tank 4, but at the same time requires higher lifting and moving technology; on the contrary, although the overly short segment is easy to carry, it will increase the number of interfaces and affect the sealing and structural strength of the tank 4. The 8-12 meter interval cleverly balances these two considerations, which is convenient for transportation and meets the effective volume requirements of the tank 4.

[0045] In this embodiment, refer to Figure 2 The anti-floating device 5 includes an anti-floating plate, which is located on the upper part of the secondary lining inverted arch wall. The main function of the anti-floating plate is to prevent the storage tank 4 from deviating from the predetermined track due to tilting or vibration during installation or transportation. The anti-floating plate is placed on the top of the secondary lining inverted arch wall. Through physical constraints, the freedom of movement of the storage tank 4 in the vertical direction is limited to ensure that the storage tank 4 will not drift horizontally or float up and down when moving longitudinally, thereby maintaining a stable state; the sliding support device 6 is composed of a sliding shoe and a roller or slider installed at the bottom thereof. The roller or slider is embedded in the pre-laid slide rail 3, forming an efficient linear motion guide system. When the storage tank 4 segment moves in the tunnel 1, the roller slides along the slide rail 3, which greatly reduces the friction resistance, ensures the smooth sliding of the storage tank 4 segment, and also reduces the pressure on the structure of the storage tank 4 itself, avoiding damage caused by friction or collision. Through the combined effect of the anti-floating plate and the sliding support device 6, the storage tank 4 always maintains a high degree of stability during the movement, effectively preventing the storage tank 4 from swinging or losing control due to the complex and changeable environment of the tunnel 1.

[0046] In addition, refer to Figure 2 In order to further enhance the stability and control accuracy of the storage tank 4 during movement, each section of the storage tank 4 is equipped with at least two sets of anti-floating devices 5 and sliding support devices 6. In this embodiment, four sets are provided, which are located on opposite sides of the storage tank 4, two sets each. Such a layout design can be evenly distributed around the storage tank 4 to form an all-round support system, effectively preventing the storage tank 4 from shaking or deflecting in any direction, and ensuring the absolute stability of the storage tank 4 during transportation and installation in the tunnel 1. The precise layout of multiple sets of anti-floating devices 5 and sliding support devices 6 ensures the precise positioning and directional movement of the storage tank 4 in the tunnel 1, improves the installation accuracy, and reduces the subsequent debugging workload.

[0047] The above are only preferred embodiments of the present invention, and are not intended to limit the implementation methods and protection scope of the present invention. Those skilled in the art should be aware that all solutions obtained by equivalent substitutions and obvious changes made using the description and illustrations of the present invention should be included in the protection scope of the present invention.

Claims

1. A construction method for installing an extra-long horizontal storage tank in a circular tunnel in a mountain, characterized in that: The following steps are involved: Step 1: excavate and initially support the mountain circular tunnel, then construct a secondary lining inverted arch surface inside the tunnel, the inverted arch surface is constructed in predetermined sections, the longitudinal highest point of which is located below the center line of the tunnel, and track fixing components and grouting pipes are pre-buried during the construction process; Step 2: When the concrete of the secondary lining arch surface reaches the design strength index, the arc surface of the inner side is roughened to strengthen the bonding strength of the contact surface between the new and old concrete; at the same time, a slide rail is set in the middle of the secondary lining arch wall; Step 3: Design and manufacture the storage tank, divide the storage tank into several sections, and ensure that the tail of each section extends at least 1 meter beyond the corresponding secondary lining arch section as the welding preparation area for adjacent sections; install the anti-floating device and the sliding support device in the central part of the outside of the storage tank; Step 4: Use a trackless ground-level mobile vehicle to load the tank segment, and use a hydraulic crawler and a hydraulic jack provided on the invert surface of the secondary lining to push the tank to the predetermined position; Step 4: After the initial positioning of the tank segment is completed, the anti-floating device is lifted with the help of a jack, and the sliding support device is removed to place the tank segment securely on the invert surface; then all temporary auxiliary facilities are removed and the tank segment is locked; Step 5: Use steel formwork to cover the top gap between the tank segment and the initial support, and perform concrete pouring in this area; When the concrete hardens to the specified level, pressurized cement slurry is injected through the pre-installed grouting pipe to seal the gap between the tank and the lining; Step 6. Repeat steps 3 to 5 until all tank segments are installed to form a complete and continuous extra-long horizontal tank.

2. The construction method for installing an extra-long horizontal storage tank in a circular tunnel in a mountain according to claim 1, characterized in that: The segmented construction of the secondary lining is carried out synchronously and staggered with the installation of the tank segments to provide necessary concrete pouring operation space and ensure the quality of concrete pouring and the density of the structure.

3. The construction method for installing an extra-long horizontal storage tank in a circular tunnel in a mountain according to claim 1, characterized in that: Self-compacting high-strength grouting material is used to fill the gaps between the top arch and the initial support, and between the storage tank and the secondary lining.

4. The construction method for installing an extra-long horizontal storage tank in a circular tunnel in a mountain according to claim 1, characterized in that: The trackless ground-level mobile vehicle is provided with an arc-shaped support for supporting the tank segment.

5. The construction method for installing an extra-long horizontal storage tank in a circular tunnel in a mountain according to claim 1, characterized in that: The segment length of the tank segment is designed to be 8-12 meters to facilitate flexible transportation and installation in the tunnel.

6. The construction method for installing an extra-long horizontal storage tank in a circular tunnel in a mountain according to claim 1, characterized in that: The anti-floating device comprises an anti-floating plate, and the anti-floating plate is located on the upper part of the inverted arch wall of the secondary lining.

7. The construction method for installing an extra-long horizontal storage tank in a circular tunnel in a mountain according to claim 1, characterized in that: The sliding support device comprises a sliding shoe, the bottom of which is equipped with a roller, and the roller is slidably connected in the sliding rail.

8. The construction method for installing an extra-long horizontal storage tank in a circular tunnel in a mountain according to claim 1, characterized in that: At least two sets of anti-floating devices and sliding support devices are arranged in the upper county of each section of the storage tank.

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