Tunnel invert drainage mechanism
By installing longitudinal, vertical, and circumferential blind pipes in the tunnel invert, combined with drainage layers and waterproofing membranes, the problems of low drainage efficiency and poor reliability of traditional tunnel inverts are solved. This achieves efficient groundwater discharge and structural waterproofing, and reduces maintenance costs during operation.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- 中国水利水电第七工程局有限公司
- Filing Date
- 2025-06-17
- Publication Date
- 2026-05-26
Smart Images
Figure CN224282663U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of tunnel construction technology, and in particular to a drainage and waterproofing mechanism for a tunnel invert arch. Background Technology
[0002] With the continuous advancement of high-altitude railway construction in my country, tunnel projects traversing complex hydrogeological conditions are increasing. As a key structure bearing the pressure of the strata and the effects of groundwater, the drainage and waterproofing performance of the tunnel invert directly impacts the long-term safety and stability of the tunnel. Traditional drainage and waterproofing engineering for high-altitude railway tunnel inverts suffers from low drainage efficiency, with water easily seeping through construction joints. Furthermore, in areas with abundant groundwater, the invert is susceptible to high water pressure, leading to softening, expansion, and bulging of the muddy strata. Traditional drainage measures are insufficient to effectively reduce water pressure. Utility Model Content
[0003] Therefore, it is necessary to provide a drainage mechanism for tunnel invert arches to address the problem that traditional drainage measures for invert arches in plateau railway tunnels are ineffective in draining water and reducing pressure.
[0004] A tunnel invert drainage mechanism includes:
[0005] Longitudinal blind pipes at the tunnel bottom are installed in the surrounding rock at the tunnel bottom and extend along the tunnel axis;
[0006] A vertical blind pipe is installed perpendicular to the longitudinal blind pipe at the bottom of the tunnel and is connected to the longitudinal blind pipe at the bottom of the tunnel.
[0007] A circumferential blind pipe is arranged circumferentially with the outer circle of the tunnel lining and is connected to the longitudinal blind pipe at the bottom of the tunnel.
[0008] The drainage layer includes self-adhesive fabric, drainage board and geotextile layered sequentially on the initial support surface;
[0009] No-fines precast concrete blocks are placed on the longitudinal blind pipes of the low sidewalls;
[0010] Waterproof membrane, which wraps around the longitudinal blind pipe of the low side wall and the precast no-fines concrete block;
[0011] A horizontal blind pipe is provided on both sides of the circumferential construction joint, and a drain hole is provided on both sides of the construction joint. The drain hole is connected to the horizontal blind pipe and the longitudinal blind pipe of the low side wall.
[0012] The backing waterproofing strip is glued to the waterproofing membrane.
[0013] The waterstop is embedded in the center and a galvanized steel plate waterstop is attached to the construction joint.
[0014] The aforementioned tunnel invert arch drainage system, with its longitudinal blind pipes, vertical blind pipes, and circumferential blind pipes at the tunnel bottom working in tandem, can effectively collect and efficiently discharge groundwater. This effectively reduces water pressure at the bottom of the invert arch, prevents softening of the underlying structure and structural defects. Combined with the installation of drainage layers, waterproof membranes, transverse blind pipes, and drainage holes, it can effectively improve the waterproof performance at construction joints, reduce lining cracking and seepage, and lower maintenance costs during operation.
[0015] In one embodiment, the tunnel invert arch waterproofing mechanism further includes a turning joint, which is located at the position where the longitudinal blind hole of the low sidewall extends out of the waterproof membrane, and the joint of the turning joint is sealed by a saddle-shaped rubber ring and sealant.
[0016] In one embodiment, the surrounding rock at the tunnel bottom is provided with an arrangement groove formed by a bottom wall and two side walls inclined to the bottom wall and opposite to each other, and the longitudinal blind pipe at the tunnel bottom is laid in the arrangement groove.
[0017] In one embodiment, the arrangement trench is backfilled with graded crushed stone and covered with tarpaulin.
[0018] In one embodiment, the longitudinal blind pipe at the bottom of the tunnel is disconnected every 500m for zoned drainage.
[0019] In one embodiment, the vertical blind pipe at the bottom of the tunnel and the circumferential blind pipe are installed at a distance of 0.5m and 1m from the end of the downstream section, respectively.
[0020] In one embodiment, the circumferential blind pipe is arranged every 24m along the longitudinal blind pipe at the bottom of the tunnel.
[0021] In one embodiment, a steel sleeve is used to cover the longitudinal blind pipe at the front end of the invert arch, and the partition ends of the longitudinal blind pipe at the tunnel bottom are sealed with concrete.
[0022] In one embodiment, two rows of hot-melt washers are provided on opposite sides of the waterproofing board. The positions of the hot-melt washers are determined by chalk lines, with a spacing of 50cm*50cm and a circumferential spacing of 20cm.
[0023] In one embodiment, the drainage hole is installed every 3m with a slope of not less than 1.5%. Attached Figure Description
[0024] Figure 1 This is a flowchart illustrating the tunnel invert arch waterproofing and drainage construction method in some embodiments.
[0025] Figure 2 This is a schematic diagram of the tunnel bottom blind pipe arrangement in some embodiments.
[0026] Figure 3 This is a schematic diagram of the partitioned structure of the longitudinal blind pipe at the bottom of the tunnel in some embodiments.
[0027] Figure 4 This is a schematic diagram of the structure of a longitudinal blind pipe at the bottom of a tunnel in some embodiments.
[0028] Figure 5 This is a schematic diagram of the blind pipe arrangement structure at the construction joint in some embodiments.
[0029] Figure 6 This is a schematic diagram of the structure at the joint of the transverse blind pipe and the longitudinal blind pipe at the low side wall in some embodiments.
[0030] Figure 7 A schematic diagram of a saddle-shaped rubber ring provided for a bend joint in some embodiments.
[0031] Figure 8 This is a schematic diagram of the structure for fixing spiral reinforcing bars in some embodiments.
[0032] Figure label:
[0033] 11. Layout trench; 12. Longitudinal blind pipe at the tunnel bottom; 13. Corrugated tarpaulin; 14. Graded crushed stone; 15. Vertical blind pipe at the tunnel bottom; 16. Circumferential blind pipe; 17. Anti-crystallization seal; 18. Longitudinal blind pipe at the low sidewall; 19. Horizontal blind pipe; 21. Drain hole; 22. Turning joint; 23. Saddle-shaped rubber ring; 25. Spiral reinforcement; 26. Reinforcing steel frame; 27. Waterproof membrane; 28. No-fines concrete precast blocks. Detailed Implementation
[0034] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.
[0035] In the description of this application, it should be understood that if terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.
[0036] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.
[0037] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.
[0038] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.
[0039] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.
[0040] With the continuous advancement of high-altitude railway construction in my country, tunnel projects traversing complex hydrogeological conditions are increasingly common. As a key structure bearing the pressure of the strata and the effects of groundwater, the drainage and waterproofing performance of the tunnel invert directly affects the long-term safety and stability of the tunnel. Current technologies for drainage and waterproofing in high-altitude railway tunnel inverts face the following problems:
[0041] 1. In areas with well-developed groundwater, the invert arch is easily affected by high water pressure, leading to problems such as softening, swelling, and bulging of the muddy strata. Traditional drainage measures are difficult to effectively drain water and reduce pressure.
[0042] 2. The blind pipe layout is not reasonable and has low drainage efficiency, which makes it easy to blockage and leads to frequent water leakage in the lining.
[0043] 3. Improper waterproofing at the junction of the low sidewall and the invert arch can easily lead to water leakage through the construction joint, affecting the tunnel environment and structural safety;
[0044] 4. Existing construction methods lack precise control over key processes such as initial support treatment, blind pipe fixing, and drainage board laying, resulting in low reliability of the drainage system.
[0045] To address the aforementioned issues, this application provides a method for constructing drainage and waterproofing for tunnel invert arches, as well as a drainage and waterproofing mechanism for tunnel invert arches.
[0046] refer to Figure 1 As shown, Figure 1 The diagram illustrates a flow chart of the tunnel invert drainage construction method in some embodiments of this application. The tunnel invert drainage construction method and tunnel invert drainage mechanism provided in this application can be applied to any suitable tunnel project, such as plateau railway tunnels.
[0047] In some embodiments, the tunnel invert drainage construction method includes:
[0048] Step S110: Construction Preparation. Technical personnel thoroughly review the construction drawings and, based on the actual project conditions, prepare detailed work instructions and safety technical documents. They organize detailed technical and safety training for construction personnel to ensure they are familiar with the construction process and safety points, and to ensure that key construction points and safety precautions are effectively communicated. All required materials and equipment undergo rigorous screening and testing to ensure their quality and performance meet construction requirements.
[0049] In some embodiments, the materials required for construction include, but are not limited to, φ80DG blind pipes, φ80WG blind pipes, self-adhesive cloth, drainage boards, geotextiles, waterstops, etc., and the equipment required for construction includes, but is not limited to, climbing welding machines, welding guns, hot air blowers, nail guns, etc.
[0050] Step S120, base surface treatment: cut and chisel away the exposed steel bar ends, surrounding rock measurement points and bulges on the initial support surface, and level with mortar.
[0051] In some embodiments, in step S120, a high-precision 3D scanner can be used to perform a comprehensive inspection of the initial support surface in order to promptly address any encroachment on the initial support surface. For example, this includes precisely cutting, chiseling away, and leveling with mortar on exposed rebar ends, surrounding rock measurement points, and bulges.
[0052] In some embodiments, in step S120, the flatness of the initial support surface is controlled to below 5%, for example, to 4%, by processing the initial support surface, in order to meet the construction requirements.
[0053] Combination Figure 1 , Figure 2 and Figure 3 As shown, in step S130, the tunnel bottom blind pipes are arranged by installing a longitudinal blind pipe 12 extending along the tunnel's axial direction in the surrounding rock of the tunnel bottom, a vertical blind pipe 15 perpendicular to the longitudinal blind pipe 12, and a circumferential blind pipe 16 arranged along the outer circumference of the tunnel lining. Both the vertical blind pipe 15 and the circumferential blind pipe 16 are connected to the longitudinal blind pipe 12. The longitudinal blind pipe 12, the vertical blind pipe 15, and the circumferential blind pipe 16 work together to enhance groundwater drainage.
[0054] In some embodiments, an arrangement trench 11, formed by a bottom wall and two side walls inclined to the bottom wall and arranged opposite each other, can be excavated on the surrounding rock of the tunnel bottom after the invert arch has been excavated and cleared. The longitudinal blind pipe 12 of the tunnel bottom is laid in the arrangement trench 11. The bottom width of the arrangement trench 11 can be 10cm, and the slope of the two side walls is 1:1. The longitudinal blind pipe 12 of the tunnel bottom can be a φ80DG blind pipe.
[0055] Combination Figure 3 and Figure 4 As shown, in some embodiments, the longitudinal blind pipe 12 at the bottom of the tunnel is disconnected every 500m for zoned drainage. Vertical blind pipes 15 and circumferential blind pipes 16 are densely installed at the downstream end of each zone, 0.5m and 1m from the end, to enhance groundwater drainage. Figure 4 The diagram shows one section of the longitudinal blind pipe 12 at the bottom of the tunnel.
[0056] In some embodiments, a steel sleeve is used to cover the longitudinal blind pipe 12 at the front end of the invert arch, and the section ends of the longitudinal blind pipe 12 at the tunnel bottom are sealed with concrete to protect the longitudinal blind pipe 12 at the tunnel bottom and prevent the blind pipe from becoming blocked.
[0057] In some embodiments, the circumferential blind pipe 16 is also arranged every 24m (every 2 slabs) along the longitudinal blind pipe 12 at the tunnel bottom. The circumferential blind pipe 16 is connected to the longitudinal blind pipe 12 at the tunnel bottom through a four-way connector. The joint is wrapped with geotextile and tied tightly with wire to prevent grout from entering the blind pipe joint. The φ80WG blind pipe above the surrounding rock at the tunnel bottom is connected to the φ80DG blind pipe at the tunnel bottom through a direct connector. A self-made clamp is used to accurately position the bending arc and lead-out position of the blind pipe. The self-made clamp can be welded from two cold-bent Φ16 steel bars and a circular ring with a diameter of 8cm and a spacing of 50cm between the steel bars.
[0058] In some embodiments, after the longitudinal blind pipe 12, the vertical blind pipe 15, and the circumferential blind pipe 16 at the bottom of the tunnel are laid, the arrangement trench 11 is backfilled with graded crushed stone 14, and a colored tarpaulin 13 is covered on the arrangement trench 11. The particle size of the graded crushed stone 14 can be 2.5cm-5cm, the width of the colored tarpaulin 13 can be 50cm, and the colored tarpaulin 13 is fixed with semi-circular clamps at longitudinal intervals of 1cm-1.5cm.
[0059] Step S140: On the wall, use a total station to mark the control lines, including the top control line of the long rebar, the top control line of the geotextile, the longitudinal blind pipe control line of the low side wall, the geotextile control line behind the narrow drainage board, the center line of the geotextile behind the narrow drainage board, the circumferential construction joint of the invert arch, the end control line of the 135° bend, the top control line of the waterproof board, the top control line of the low side wall, and the top control line of the short rebar. The error of each control line should be controlled within the allowable range to provide an accurate benchmark for subsequent steps such as laying the drainage layer. The allowable error range can refer to the requirements of industry specifications such as the "Construction Quality Acceptance Standard for High-Speed Railway Tunnel Engineering".
[0060] Step S150: Lay the drainage layer. Lay self-adhesive fabric on the initial support surface, lay drainage board on the self-adhesive fabric, and lay geotextile on the drainage board. In some embodiments, drainage board is installed between the self-adhesive fabric and geotextile at the middle of each lining and at the construction joint. Based on the precise positioning on the wall according to the ten-line standard, the self-adhesive fabric, drainage board, and geotextile are sequentially fixed to the initial support concrete using nails with plastic washers.
[0061] In some embodiments, double rows of hot-melt washers are installed on both sides of the drainage board. The positions of the hot-melt washers are determined by chalk lines, with a spacing of 50cm*50cm and a circumferential spacing of 20cm. The bottom row of hot-melt washers is 4cm away from the top surface of the no-fines concrete. When laying the geotextile, a 15cm gap is left at the bottom as a free end, which is not fixed at the moment.
[0062] Step S160: Waterproofing with reverse wrapping of blind pipes. Fix the reverse wrapping end of the waterproofing membrane 27 to the bottom of the construction joint, and fix the free end of the geotextile to the surface of the waterproofing membrane 27. Straighten the longitudinal blind pipe 18 of the low side wall and fit it tightly against the initial support surface. Install the no-fines concrete precast block 28 on the longitudinal blind pipe 18 of the low side wall. Roll up the waterproofing membrane 27 to wrap the longitudinal blind pipe 18 of the low side wall and the no-fines concrete precast block 28.
[0063] In some embodiments, in step S160, the free end of the geotextile reserved in step S150 is lifted, the reverse-wrapped end of the waterproof membrane 27 is fixed to 25cm below the construction joint, and the lower free end of the geotextile is fixed to the surface of the waterproof membrane 27. The waterproof membrane 27 is rolled up and placed on the work platform. Then, the longitudinal blind pipe control line of the low side wall is strictly installed. The longitudinal blind pipe 18 of the low side wall is straightened and tightly attached to the initial support surface. After installing the no-fines concrete precast block 28 on the longitudinal blind pipe 18 of the low side wall, the waterproof membrane 27 is rolled up upwards, the longitudinal blind pipe 18 of the low side wall and the no-fines concrete precast block 28 are reverse-wrapped, and fixed at a position more than 1m above the construction joint. It will then overlap with the waterproof membrane of the arch wall later.
[0064] refer to Figure 5 , Figure 6 , Figure 7 and Figure 8 As shown, in step S170, a transverse drainage system is installed, with transverse blind pipes 19 installed on both sides of the circumferential construction joint and drainage holes 21 installed on both sides of the construction joint. The drainage holes 21 and the transverse blind pipes 19 are connected to the longitudinal blind pipes 18 of the low side wall.
[0065] In step S170, a saddle-shaped rubber ring 23 is installed at the joint of the horizontal blind pipe 19 and the vertical blind pipe 18 of the low side wall. The saddle-shaped rubber ring 23 is bonded to the waterproof membrane 27 with structural adhesive. A custom clamp is installed to fix the horizontal blind pipe 19, and a card box is installed at the opening for positioning.
[0066] Specifically, in some embodiments, a Φ100WG blind pipe is installed at 86cm on each side of the circumferential construction joint to form a transverse blind pipe 19. The longitudinal blind pipe 18 (Φ100DG) of the low side wall is opened at the position where it extends out of the waterproof membrane 27 and extends out to a 135° bend joint 22. The joint is sealed with a saddle-shaped rubber ring 23 and sealant, and the waterproof membrane 27 is applied to the outside to strengthen the seal and prevent concrete slurry from entering the transverse blind pipe 19 and affecting the drainage effect. At the joint of the transverse blind pipe 19 and the longitudinal blind pipe 18 of the low side wall, the transverse blind pipe 19 is fixed by setting a spiral steel bar 25 to prevent pipe displacement.
[0067] To facilitate the connection between the horizontal blind pipe 19 and the anti-crystallization seal 17, a turning joint 22 is installed inside the low side wall. A Φ110 PVC pipe is installed 30cm from each side of the construction joint as a drain hole 21. Φ110 PVC drain holes 21 are installed every 3m along the low side wall, with a slope of not less than 1.5%. Figure 5 This illustrates the pipe layout at the construction joint, with the saddle-shaped rubber ring 23 arranged as a reference. Figure 6 and Figure 7 As shown, the arrangement of spiral reinforcing bars 25 is as follows. Figure 8 As shown, the spiral steel bar 25 has a size of φ8 and a pitch of 10cm, and is surrounded by a φ20 skeleton steel bar 26.
[0068] Step S180. Waterstop arrangement: Adhere the back-attached waterstop to the waterproof membrane 27, adhere the embedded waterstop to the galvanized steel plate waterstop, and fix the galvanized steel plate waterstop at the construction joint.
[0069] In some embodiments, in step S180, the rubber-backed waterstop has a reserved length of 1.3m on the concrete surface of the low side wall and is glued to the waterproof membrane 27. Before gluing, the waterstop and waterproof membrane 27 are wiped clean. The rubber embedded waterstop has a reserved length of 1m on the concrete surface of the low side wall and is glued to the galvanized steel plate waterstop and fixed with clamps. The galvanized steel plate waterstop is fixed with custom-made clamps, with a reserved end length of not less than 1m. In some embodiments, the rubber embedded waterstop is installed using a hinged steel end mold and U-shaped steel bars, resulting in a smooth line and centered position, effectively ensuring the waterproof performance of the construction joint.
[0070] The above-mentioned tunnel invert arch waterproofing and drainage construction method, with the longitudinal blind pipe 12, the vertical blind pipe 15, and the circumferential blind pipe 16 at the tunnel bottom working together, can effectively collect and efficiently discharge groundwater, thereby effectively reducing the water pressure at the bottom of the invert arch, preventing the bottom layer from softening and structural defects. Combined with the setting of waterproofing and drainage layers, waterproof membrane 27, transverse blind pipes 19, and drainage holes 21, it can effectively improve the waterproofing performance at construction joints, reduce defects such as lining cracking and seepage, and reduce maintenance costs during operation.
[0071] Specifically, the above-mentioned tunnel invert arch waterproofing and drainage construction method can achieve the following:
[0072] 1. Construct a zoned and efficient drainage system: By dividing the tunnel into 12 zones with longitudinal blind pipes at the bottom, independently dividing the blind pipes in the low sidewalls, and centrally diverting and draining groundwater with sand-free concrete, the system achieves graded collection and directional discharge of groundwater, reduces the long-term water pressure on the invert arch structure, and avoids diseases such as softening and bulging of the muddy strata.
[0073] 2. Improve the reliability of the drainage system: Through the precise positioning of the longitudinal blind pipe 12 at the bottom of the tunnel by the arrangement of the trench 11, the sealing of the saddle-shaped rubber ring 23, and the fixing of the spiral steel bar 25, the problems of easy blockage, easy leakage of joints and pipe displacement of traditional blind pipes are solved, ensuring the long-term smooth flow of drainage channels.
[0074] 3. Strengthen waterproofing of construction joints and structural joints: By fixing waterstops in stages (back-attached type, embedded type, combination of galvanized steel plate waterstops), using the 27 reverse wrapping process of waterproof board and sealant to strengthen the seal, the seepage path of groundwater through construction joints and structural joints is blocked, thereby improving the overall waterproof performance of the lining structure.
[0075] It should be noted that in step S140, the control line on the top surface of the long reinforcing bar is used to control the elevation position of the long reinforcing bar during the construction of the invert arch, ensuring that the installation of the long reinforcing bar meets the design requirements, thereby ensuring the strength and stability of the invert arch structure. In subsequent steps such as concrete pouring, the control line on the top surface of the long reinforcing bar can prevent the long reinforcing bar from shifting position, ensuring its load-bearing performance in the structure.
[0076] The upper control line of the geotextile can be used to control the position of the upper end of the geotextile during the laying process in step S150, ensuring the accuracy of the laying height of the geotextile, so that it can be reasonably connected with other components and effectively play its protective and filtering role.
[0077] The control line of the longitudinal blind pipe 18 of the low side wall can be used to accurately locate the installation position of the longitudinal blind pipe 18 of the low side wall in step S160, ensuring that the longitudinal blind pipe 18 of the low side wall is straight and meets the drainage slope requirements, so that groundwater can be discharged smoothly through the longitudinal blind pipe 18 of the low side wall.
[0078] The control line and center line of the geotextile behind the narrow-width waterproofing board are used in step S150 to control the laying position and center line position of the geotextile behind the narrow-width waterproofing board, respectively, to ensure that the geotextile is laid flat and accurately positioned so as to closely cooperate with the waterproofing board and work together to play a waterproofing role.
[0079] The circumferential construction joint of the invert arch can be used in steps S160, S170 and S180 to provide a positioning reference for construction operations such as the reverse wrapping of the waterproof membrane 27, the setting of the transverse blind pipe 19 and the drainage hole 21, and the installation of the waterstop at the circumferential construction joint of the invert arch, thereby ensuring the waterproof performance of the construction joint.
[0080] The bend end control line can be used to position the 135° bend joint 22 in step S7, ensuring that the bend joint 22 is in an accurate position, so that the transverse blind pipe 19 can be smoothly connected to the longitudinal blind pipe 12 at the bottom of the tunnel, the drain hole 21 and other components, ensuring the sealing and drainage effect of the drainage system.
[0081] The control line on the top surface of the waterproof membrane can be used for the reverse wrapping construction of the waterproof membrane 27 in step S160 to control the elevation of the top surface of the waterproof membrane 27, so that the waterproof membrane 27 fits tightly with other components and effectively prevents groundwater leakage.
[0082] The control line on the top surface of the low sidewall can be used to control the elevation and position of the top surface of the low sidewall during the construction process, ensuring accurate connection between the low sidewall and the invert arch and other structures, and guaranteeing the stability and waterproof performance of the entire tunnel structure.
[0083] The top surface control line of the short reinforcing bars is used to control the top surface elevation of the short reinforcing bars during the construction of the invert arch, ensuring that the installation position of the short reinforcing bars is accurate, meeting the design requirements of the invert arch structure, and enhancing the structural strength of the invert arch.
[0084] The above-mentioned tunnel invert waterproofing and drainage construction method can achieve the following effects:
[0085] 1. By using the longitudinal blind pipe 12 at the bottom of the tunnel to be disconnected at 500m intervals and the vertical blind pipe 15 and circumferential blind pipe 16 at the downstream end of the tunnel, the zoned collection and efficient discharge of groundwater can be achieved, effectively reducing the water pressure at the bottom of the invert arch and preventing ground softening and structural damage.
[0086] 2. The longitudinal blind pipes of the low side wall are disconnected and divided into independent sections for each slab. Combined with the centralized drainage of water after lining with no-fines concrete, water seepage is prevented from accumulating at the junction of the low side wall and the invert arch, thus improving the waterproof performance of the construction joint.
[0087] 3. The details of the arrangement of the trench 11 to fix the longitudinal blind pipe 12 at the bottom of the tunnel, the saddle-shaped rubber ring 23 for sealing, and the spiral steel bar 25 for positioning are handled to ensure the installation accuracy of the blind pipe, reduce the risk of blockage, and improve the reliability of the drainage system.
[0088] 4. Control of processes such as substrate treatment, air tightness testing, and blind pipe water flow test ensures the quality of drainage board installation and unobstructed drainage system; finished product protection measures effectively prevent damage to drainage facilities during construction.
[0089] 5. Reduce lining cracks, water seepage and other defects, lower maintenance costs during operation; protect the environment, avoid excessive groundwater discharge, and comply with the principle of "combining prevention, drainage, interception and blocking, and comprehensive management".
[0090] Based on the tunnel invert drainage construction method described in any of the above embodiments, this application also provides a tunnel invert drainage mechanism, which can be manufactured by the above tunnel invert drainage construction method.
[0091] In some embodiments, the tunnel invert drainage mechanism includes a longitudinal blind pipe 12 at the tunnel bottom, a vertical blind pipe 15 at the tunnel bottom, a circumferential blind pipe 16, a drainage layer, a precast no-fines concrete block 28, a waterproof membrane 27, a transverse blind pipe 19, a back-attached waterstop, a centrally embedded waterstop, and a galvanized steel plate waterstop. The longitudinal blind pipe 12 at the tunnel bottom is set in the surrounding rock at the tunnel bottom and extends along the tunnel axis; the vertical blind pipe 15 at the tunnel bottom is set perpendicular to the longitudinal blind pipe 12 at the tunnel bottom and is connected to the longitudinal blind pipe 12 at the tunnel bottom; the circumferential blind pipe 16 is arranged circumferentially along the outer circle of the tunnel lining and is connected to the longitudinal blind pipe 12 at the tunnel bottom; the waterproof layer includes self-adhesive cloth, waterproof board and geotextile stacked in sequence on the initial support surface; the no-fines concrete precast block 28 is set on the longitudinal blind pipe 18 of the low side wall; the waterproof board 27 wraps around the longitudinal blind pipe 18 of the low side wall and the no-fines concrete precast block 28; the transverse blind pipe 19 is set on both sides of the circumferential construction joint, and the drainage hole 21 is set on both sides of the construction joint. The drainage hole 21 is connected to the transverse blind pipe 19 and the longitudinal blind pipe 18 of the low side wall; the back-adhesive waterstop is glued to the waterproof board 27; the galvanized steel plate waterstop is fixed at the construction joint position and glued to the embedded waterstop.
[0092] In some embodiments, the tunnel arch drainage mechanism further includes a bend joint 22, which is located at the position where the longitudinal blind pipe 18 of the low sidewall extends out of the waterproof plate 27, and the joint of the bend joint 22 is sealed by a saddle-shaped rubber ring 23 and sealant.
[0093] In some embodiments, an arrangement trench 11 is provided on the surrounding rock at the tunnel bottom, formed by a bottom wall and two side walls inclined to the bottom wall and opposite to each other, and a longitudinal blind pipe 12 is laid in the arrangement trench 11. The arrangement trench 11 is backfilled with graded crushed stone 14, and the arrangement trench 11 is covered with tarpaulin 13.
[0094] In some embodiments, the longitudinal blind pipe 12 at the tunnel bottom is disconnected every 500m for zoned drainage. Vertical blind pipes 15 and circumferential blind pipes 16 are installed at the downstream end of each zone, 0.5m and 1m from the end respectively. The circumferential blind pipe 16 is arranged every 24m along the longitudinal blind pipe 12 at the tunnel bottom. A steel sleeve is used to cover the longitudinal blind pipe 12 at the front end of the invert, and the zoned ends of the longitudinal blind pipe 12 are sealed with concrete.
[0095] In some embodiments, two rows of hot melt washers are provided on opposite sides of the waterproof and drainage board. The positions of the hot melt washers are determined by chalk lines, with a spacing of 50cm*50cm and a circumferential spacing of 20cm.
[0096] In some embodiments, a drainage hole 21 is provided every 3m with a slope of not less than 1.5%.
[0097] The specific structural configuration of each part of the tunnel invert drainage mechanism and the effects it can achieve can be obtained by referring to the above-mentioned description of the tunnel invert drainage construction method, and will not be repeated in this application.
[0098] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0099] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.
Claims
1. A tunnel inverted arch waterproof and drainage mechanism, characterized in that, include: Longitudinal blind pipes at the tunnel bottom are installed in the surrounding rock at the tunnel bottom and extend along the tunnel axis; A vertical blind pipe is installed perpendicular to the longitudinal blind pipe at the bottom of the tunnel and is connected to the longitudinal blind pipe at the bottom of the tunnel. A circumferential blind pipe is arranged circumferentially with the outer circle of the tunnel lining and is connected to the longitudinal blind pipe at the bottom of the tunnel. The drainage layer includes self-adhesive fabric, drainage board and geotextile layered sequentially on the initial support surface; No-fines precast concrete blocks are placed on the longitudinal blind pipes of the low sidewalls; Waterproof membrane, which wraps around the longitudinal blind pipe of the low side wall and the precast no-fines concrete block; A horizontal blind pipe is provided on both sides of the circumferential construction joint, and a drain hole is provided on both sides of the construction joint. The drain hole is connected to the horizontal blind pipe and the longitudinal blind pipe of the low side wall. The backing waterproofing strip is glued to the waterproof membrane; The embedded waterstop and the galvanized steel plate waterstop are fixed at the construction joint and are glued to the embedded waterstop.
2. The tunnel invert waterproofing mechanism according to claim 1, characterized in that, The tunnel invert arch waterproofing mechanism also includes a turning joint, which is located at the position where the longitudinal blind hole of the low side wall extends out of the waterproof membrane. The joint of the turning joint is sealed by a saddle-shaped rubber ring and sealant.
3. The tunnel invert arch drainage mechanism according to claim 1, characterized in that, The tunnel bottom surrounding rock is provided with an arrangement groove formed by the bottom wall and two side walls that are inclined to the bottom wall and opposite to each other, and the longitudinal blind pipe of the tunnel bottom is laid in the arrangement groove.
4. The tunnel invert arch drainage mechanism according to claim 3, characterized in that, The arrangement trench is backfilled with graded crushed stone and covered with tarpaulin.
5. The tunnel invert arch drainage mechanism according to claim 1, characterized in that, The longitudinal blind pipes at the bottom of the tunnel are disconnected every 500m for zoned drainage.
6. The tunnel invert arch drainage mechanism according to claim 5, characterized in that, The vertical blind pipe at the bottom of the tunnel and the circumferential blind pipe are installed at a distance of 0.5m and 1m from the end of the downstream section, respectively.
7. The tunnel invert arch drainage mechanism according to claim 5, characterized in that, The circumferential blind pipe is arranged every 24m along the longitudinal blind pipe at the bottom of the tunnel.
8. The tunnel invert arch drainage mechanism according to claim 5, characterized in that, The longitudinal blind pipe at the tunnel bottom is installed using a steel sleeve at the front end of the invert arch, and the section ends of the longitudinal blind pipe at the tunnel bottom are sealed with concrete.
9. The tunnel invert arch drainage mechanism according to claim 1, characterized in that, Two rows of hot-melt washers are provided on opposite sides of the waterproof and drainage board. The positions of the hot-melt washers are determined by chalk lines, with a spacing of 50cm*50cm and a circumferential spacing of 20cm.
10. The tunnel invert arch drainage mechanism according to claim 1, characterized in that, The drainage holes are installed every 3 meters, with a slope of not less than 1.5%.