A drainage plate for a tunnel secondary lining construction joint

Abstract

The utility model provides a kind of drainage plate for tunnel secondary lining construction joint, it is related to drainage technical field for tunnel construction joint, the utility model is provided with several parallel continuous inverted "V" type rib as water guide structure on plate body, constitutes an efficient organized drainage system, when groundwater seeps from tunnel primary support surface, will be immediately introduced into the drainage groove between inverted "V" type rib, under the action of gravity, water flow is not vertically down, but is shunted to left and right sides along the two sides of inverted "V" type inclined plane, and is directed to the edge of plate body, since the width of plate body is greater than or equal to the interval of annular blind pipe, ensure that the two side edges of drainage plate can directly cover or butt joint on the upper of preset annular blind pipe, eliminate the waterlogging hidden danger on both sides of construction joint center line, significantly reduce the leakage risk and water pressure accumulation of the part, thereby improve the overall durability of secondary lining concrete and the safety of tunnel operation.

Description

Technical Field

[0001] This utility model relates to the field of drainage technology for tunnel construction joints, and in particular to a drainage board for tunnel secondary lining construction joints. Background Technology

[0002] In tunnel and underground engineering construction, groundwater management follows the principle of "combining prevention, drainage, interception, and blocking," with drainage being a key aspect. Currently, the common drainage method used in tunnel engineering is to lay circumferential and longitudinal blind pipes between the initial support and the secondary lining to form a drainage system, which then centrally drains the water to side ditches or central ditches before discharging it outside the tunnel.

[0003] Due to construction process requirements, secondary lining needs to be poured in sections, which will leave construction joints. In order to ensure the structural strength and water-stopping effect at the construction joints, the longitudinal blind pipes cannot be placed close to the construction joints and usually need to be kept at a certain distance. This results in groundwater not being effectively collected by the longitudinal blind pipes within a range of about 30 centimeters on both sides of the center line of the construction joint, forming a "drainage blind zone". Groundwater in this area can only flow freely or accumulate, increasing the risk of leakage at the construction joint.

[0004] In view of this, this application designs a drainage board for construction joints of tunnel secondary lining, and this case arises from this. Utility Model Content

[0005] To solve the above problems, the technical solution of this utility model is as follows: A drainage board for construction joints of tunnel secondary lining includes a board body, one side of which is a plane, and the other side of which is provided with a plurality of parallel water guiding structures. The plurality of water guiding structures are continuous inverted "V" shaped ribs, and a drainage groove is formed between adjacent water guiding structures. The width of the board body is greater than or equal to the spacing of the circumferential blind pipes between two adjacent secondary linings of the tunnel.

[0006] Preferably, the plate body has a transversely protruding water-blocking strip at the end where the water-guiding structure is located and away from the tip of the water-guiding structure.

[0007] Preferably, a blank area is provided between the water-blocking strip and the end of the plate away from the tip of the water-guiding structure.

[0008] Preferably, each of the aforementioned water guiding structures includes two inclined water guiding ridges, the angle between the water guiding ridges and the horizontal direction being 30° to 60°.

[0009] Preferably, the distance between adjacent water-guiding structures is 20mm to 50mm.

[0010] Preferably, the height of the water guide rib is 5mm to 10mm.

[0011] Preferably, the cross-section of the water-guiding structure is rectangular.

[0012] Preferably, the drainage board is made of a high molecular polymer material.

[0013] The technical solution provided by this utility model has the following beneficial effects: This invention utilizes a series of parallel, continuous inverted "V"-shaped ribs on the slab as a water-guiding structure, forming a highly efficient and organized drainage system. When groundwater seeps from the surface of the tunnel's initial support, it is immediately introduced into the drainage channels between the inverted "V"-shaped ribs. Under the influence of gravity, the water flow is not vertical but rather diverted to the left and right sides along the sloping sides of the inverted "V" shape and directed to the edge of the slab. Since the width of the slab is greater than or equal to the spacing of the circumferential blind pipes, it ensures that the two edges of the drainage slab can directly cover or connect to the pre-set circumferential blind pipes, thereby guiding the collected groundwater to the circumferential blind pipes. This eliminates the potential for water accumulation on both sides of the construction joint centerline, significantly reducing the risk of leakage and water pressure buildup in this area, thus improving the overall durability of the secondary lining concrete and the safety of tunnel operation. Attached Figure Description

[0014] The accompanying drawings, which are provided to further illustrate the present invention and constitute a part of the present invention, illustrate exemplary embodiments of the present invention and are used to explain the present invention, but do not constitute an undue limitation of the present invention.

[0015] in: Figure 1 This is a top view of the present invention; Figure 2 This is a sectional view of the present invention; Figure 3 This is a diagram showing the use of this utility model.

[0016] Label Explanation: 1. Slab; 2. Water guiding structure; 3. Drainage channel; 4. Water intercepting strip; 5. Blank area; 6. Water guiding ridge; 7. Construction joint; 8. Circumferential blind pipe; 9. Longitudinal blind pipe. Detailed Implementation

[0017] To make the technical problem to be solved, the technical solution, and the beneficial effects of this utility model clearer and more understandable, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this utility model and are not intended to limit this utility model.

[0018] Please see Figures 1 to 3This invention relates to a drainage board for tunnel secondary lining construction joints, as the preferred embodiment of the present invention. The board includes a board body 1, one side of which is flat, and the other side of which has several parallel water-guiding structures 2. These water-guiding structures 2 are continuous inverted "V"-shaped ribs, and drainage channels 3 are formed between adjacent water-guiding structures 2. The width of the board body 1 is greater than or equal to the spacing of circumferential blind pipes 8 between two adjacent secondary linings of the tunnel. The drainage channels 3 guide water flow to or near the circumferential blind pipes 8, and the water flow in the circumferential blind pipes 8 then passes through longitudinal blind pipes. 9. The slab 1 has several parallel and continuous inverted "V"-shaped ribs on one side, forming an efficient water-guiding network. After groundwater seeps out, it is immediately guided into the drainage channel 3 between the "V"-shaped ribs, and according to the principle of fluid mechanics, it is directed to both sides under the action of gravity along the inverted "V"-shaped slope, rather than flowing freely downwards. At the same time, in this embodiment, the width of the slab 1 is designed to be equal to the spacing of the circumferential blind pipes 8, and the width is greater than or equal to the distance of the circumferential blind pipes 8 between the two secondary linings. In specific production, it can be 0.8m, 1m, or 1. Different models with a 2m uniform width are available for construction selection. A width greater than the distance between two blind pipes can achieve drainage, but this increases cost. Furthermore, due to the thickness of the drainage board, it will form a bulge at the circumferential blind pipe 8, affecting the flatness of the waterproofing board. Ensuring that the two edges of the drainage board can directly connect to or cover the circumferential blind pipe 8 allows for precise and reliable channeling of collected seepage water into the tunnel's main drainage system. This solution can efficiently eliminate drainage blind spots, actively and thoroughly draining accumulated water within approximately 30 cm on each side of the centerline of construction joint 7, eliminating hydrostatic pressure in this area. Simultaneously, it significantly improves waterproofing reliability by "guiding" instead of "blocking," reducing the reliance on a single waterstop seal at construction joint 7 and preventing leaks and calcification at the source. It also enhances structural durability, reduces long-term water erosion of the secondary lining concrete, and ensures long-term tunnel operational safety. As a standardized component, this device seamlessly integrates with the existing blind pipe system, with accurate installation and positioning, forming a complete and reliable "surface-line" drainage subsystem, improving construction quality and efficiency.

[0019] Please see Figures 1 to 3The slab 1 has a horizontally protruding water-blocking strip 4 at the end away from the tip of the water-guiding structure 2 on the side where the water-guiding structure 2 is located. The inverted "V" groove of the drainage board guides the water to flow out of the construction joint 7 area, but some residual water will always seep down. A water-blocking strip 4 is set at the bottom to block the residual water and prevent the water from flowing down. Because the grooved side of the drainage board faces the initial support, the drainage board and the initial support of the tunnel form a closed cavity on both sides. When the water is full, it will naturally flow to both sides. The water flow blocked by the water-blocking strip 4 will accumulate here. When the liquid level exceeds the height of the cavity formed by the water-blocking strip 4 and the surface of the initial support, the water flow will change direction and flow to both sides along the same guiding direction (i.e., horizontal direction) as the water-blocking strip 4 and the "V" shaped drainage groove 3, and finally flow into the runoff of the main drainage groove 3 and be discharged into the circumferential blind pipe 8. This is equivalent to providing a "second chance" for any remaining water that may leak, ensuring that all water is effectively collected and drained. As a result, a complete closed-loop system is formed, from collection and diversion to final leak prevention, which greatly improves the reliability and durability of the entire drainage solution.

[0020] Please see Figures 1 to 3 A blank area 5 is provided between the water-blocking strip 4 and the end of the plate 1 furthest from the tip of the water-guiding structure 2. During construction, the drainage board will be cut and overlapped, hence the bottom blank area 5. At the tunnel construction site, the drainage board needs to be cut and spliced ​​according to the precise position of the circumferential blind pipe 8 and the dimensions of the lining trolley. The existence of the blank area 5 allows workers to avoid directly operating on the structurally complex water-blocking strip 4 during cutting operations, preventing damage to the structural integrity of the water-blocking strip 4 due to careless cutting. The cutting line can fall on the solid and flat blank area 5, making operation simpler and increasing the margin for error. When the upper and lower drainage boards need to be vertically overlapped, the water-blocking strip 4 of the upper board can be tightly pressed against the plane of the blank area 5 of the lower board. The flat, blank area 5 provides a uniform and reliable sealing and pressure-bearing surface for the water-blocking strip 4. The combination of the two forms an effective sealing line, preventing leakage and short circuits at the overlap, ensuring the continuity and effectiveness of the entire seepage prevention system. By separating the cutting area from the functional area (water-blocking strip 4), it is ensured that the water-blocking strip 4 of each installed drainage board is complete, intact, and fully functional. Regardless of how it is cut at the top, this "seepage-proof dam" at the bottom can play a 100% water-blocking and diversion role, greatly enhancing the construction adaptability and ultimate reliability of this drainage board solution.

[0021] Please see Figures 1 to 3Each of the several water-guiding structures 2 includes two inclined water-guiding ridges 6, with the angle between the water-guiding ridges 6 and the horizontal direction being 30° to 60°. This invention limits the angle between the water-guiding ridges 6 and the horizontal direction to between 30° and 60°. Through optimized fluid dynamics design, it achieves the best balance between efficient drainage, self-cleaning, and structural stability, thereby significantly improving the comprehensive performance and long-term reliability of the drainage board. In this embodiment, the angle is 30°. According to the principle of gravity decomposition, when the angle is within the range of 30° to 60°, the magnitude of the component force is moderate. If the angle is too small, the component force is insufficient, the water flow speed is slow, and it is easy to cause poor drainage and stagnation; if the angle is too large, the increase in component force is limited, but it will bring structural drawbacks. The preferred angle range of this design can ensure that the groundwater obtains sufficient kinetic energy, so that it can be quickly and smoothly guided to the circumferential blind pipes 8 on both sides, greatly reducing the possibility of water accumulation. Moreover, this angle range ensures that the water flow can maintain a certain flow velocity and scouring force. This continuous water flow effectively removes fine silt or impurities that may accumulate in the drainage channel 3, preventing microbial adhesion and channel blockage. This gives the drainage board a long-term, maintenance-free, self-cleaning capability, ensuring the long-lasting effectiveness of the drainage function. Furthermore, an excessively large angle would make the "inverted V-shaped" ribs high and steep, requiring more material and increasing costs; it could also affect the overall flexibility and compressive strength of the board 1. The 30° to 60° design provides an effective drainage cross-sectional area while ensuring the reliable structural strength of the water guide ribs 6, economical material usage, and ease of industrial extrusion molding production.

[0022] Please see Figures 1 to 3 The vertical distance between adjacent water-guiding structures 2 is 20mm to 50mm, and in this embodiment, it is 30mm. This distance range forms a reasonable number and appropriate size of drainage channels per unit width of the slab 1. If the spacing is too small, although the number of channels increases, the cross-sectional area of ​​a single channel will be significantly reduced, making it easy to be blocked by concrete slurry or fine particles from the stratum, and the drainage capacity will be limited. If the spacing is too large, the number of channels will be too small, and when the local seepage volume is large, the water may overflow the water-guiding ribs 6, resulting in insufficient drainage. The spacing of 20mm to 50mm ensures that in the event of sudden or large seepage, the drainage system still has sufficient water flow capacity and fault tolerance, and can drain the water in time. The water-guiding structure 2 (inverted V-shaped ribs) itself is a reinforcing rib of the slab 1. This spacing range makes the distribution density of the reinforcing ribs moderate and uniform. Together, they significantly enhance the overall rigidity and compressive strength of the slab 1, enabling it to withstand the local pressure caused by the unevenness of the initial support surface, as well as the impact of trampling, collisions, or concrete pouring that may occur during construction. This prevents the slab 1 from being flattened or damaged, ensuring the long-term existence of the drainage cavity.

[0023] Please see Figures 1 to 3The height of the water guide rib 6 is 5mm to 10mm, and in this embodiment it is 8mm. This height of 5mm to 10mm provides sufficient cross-sectional area for the drainage channel 3, effectively collecting and transporting large volumes of groundwater, preventing overflow due to insufficient channel depth. Simultaneously, this height, combined with an inclination angle of 30° to 60°, allows the water flow to gain a greater potential energy difference under gravity, thus forming a rapid and powerful drainage flow. This not only improves drainage efficiency but also enhances the self-cleaning and flushing ability of the water flow, effectively removing fine particles that may accumulate in the channel and preventing clogging. Within this height range, the water guide rib 6 acts as a strong reinforcing rib. When the secondary lining concrete is poured, this structure effectively resists the impact and lateral pressure of the concrete; in long-term use, it can withstand static loads from the surrounding rock and lining, preventing the slab 1 from being flattened and deformed, ensuring the permanent existence and functional integrity of the drainage cavity. A height below 5mm results in weak structural strength and easy crushing; a height above 10mm is too rigid and not conducive to fitting uneven surfaces of the initial support.

[0024] Please see Figures 1 to 3 The cross-section of the water-guiding structure 2 is rectangular, which is one of the easiest geometric shapes to process and shape. In continuous production using extrusion processes, rectangular molds are easy to manufacture and cost-effective. Furthermore, the molten polymer flows stably within the rectangular mold, resulting in precise and consistent structural dimensions after cooling and solidification. This ensures that each drainage board has identical performance, facilitating quality control and large-scale industrial production, fundamentally reducing manufacturing costs.

[0025] Please see Figures 1 to 3 The drainage board is made of high-molecular polymer materials. In this embodiment, polyethylene or polypropylene is used. High-molecular polymer materials (such as HDPE and PP) have inherent chemical inertness and can withstand long-term erosion from common media such as acids, alkalis, and salts in groundwater, without electrochemical corrosion, rusting, or rotting. Their stable molecular structure and excellent anti-aging properties ensure that the product has the same lifespan as the tunnel structure, achieving maintenance-free long-term service and avoiding drainage system failure due to material deterioration.

[0026] In summary, this utility model, by setting several parallel and continuous inverted "V"-shaped ribs on the plate 1 as water guiding structures 2, constitutes an efficient and organized drainage system. When groundwater seeps out from the surface of the tunnel's initial support, it is immediately introduced into the drainage channel 3 between the inverted "V"-shaped ribs. Under the action of gravity, the water flow is not vertically downward, but rather splits to the left and right sides along the two inclined surfaces of the inverted "V" shape and is directed to the edge of the plate 1. Since the width of the plate 1 is greater than or equal to the spacing of the circumferential blind pipes 8, it ensures that the two sides of the drainage plate can directly cover or connect to the pre-set circumferential blind pipes 8, thereby accurately channeling the collected groundwater into the circumferential blind pipes 8, eliminating the hidden danger of water accumulation on both sides of the center line of the construction joint 7, significantly reducing the risk of leakage and water pressure accumulation in this area, and thus improving the overall durability of the secondary lining concrete and the safety of tunnel operation.

[0027] The present invention has been described above by way of example with reference to the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-described manner. Any non-substantial improvements made by adopting the inventive concept and technical solution of the present invention, or the direct application of the inventive concept and technical solution of the present invention to other occasions without modification, are all within the protection scope of the present invention.

Claims

1. A drainage board for use at construction joints of tunnel secondary lining, characterized in that, The plate (1) includes a plate body (1), one side of which is a plane, and the other side of which is provided with several parallel water guiding structures (2). The several water guiding structures (2) are continuous inverted "V" shaped ribs, and drainage grooves (3) are formed between adjacent water guiding structures (2). The width of the plate body (1) is greater than or equal to the spacing of the circumferential blind pipes (8) between two adjacent secondary linings of the tunnel.

2. The drainage board for tunnel secondary lining construction joints according to claim 1, characterized in that, The plate (1) has a transversely protruding water-blocking strip (4) on the side where the water-guiding structure (2) is provided and at the end away from the tip of the water-guiding structure (2).

3. A drainage board for tunnel secondary lining construction joints according to claim 2, characterized in that, A blank area (5) is provided between the water-blocking strip (4) and the end of the plate (1) away from the tip of the water-guiding structure (2).

4. A drainage board for tunnel secondary lining construction joints according to claim 1, characterized in that, Several of the water guiding structures (2) include two inclined water guiding ribs (6), and the angle between the water guiding ribs (6) and the horizontal direction is 30° to 60°.

5. A drainage board for tunnel secondary lining construction joints according to claim 1, characterized in that, The vertical distance between adjacent water-guiding structures (2) is 20mm to 50mm.

6. A drainage board for tunnel secondary lining construction joints according to claim 4, characterized in that, The height of the water guide rib (6) is 5mm to 10mm.

7. A drainage board for tunnel secondary lining construction joints according to claim 1, characterized in that, The cross-section of the water-guiding structure (2) is rectangular.

8. A drainage board for tunnel secondary lining construction joints according to claim 1, characterized in that, The drainage board is made of high molecular polymer material.

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