A device for draining deformation joints of a tunnel bottom plate

Abstract

This invention provides a drainage device for expansion joints in the floor slab of an open-cut tunnel, comprising: a receiving groove; a supporting member arranged along the length of the expansion joint, spanning the expansion joint within the receiving groove, and forming a water collection channel between its side facing the bottom of the receiving groove and the bottom of the receiving groove; wherein the supporting member has opposing first and second sides, the first side being fixed to the bottom of the receiving groove on one side of the expansion joint, and the second side overlapping the bottom of the receiving groove; a deformation buffer seal body filling a reserved space between the second side of the supporting member and the corresponding side wall of the receiving groove, so as to undergo elastic deformation within this space to maintain continuous sealing when the expansion joint is repeatedly opened and closed; and a drain pipe, one end of which is connected to the water collection channel, and the other end for draining the liquid collected in the water collection channel. This device combines joint protection, deformation adaptation, composite sealing, and effective drainage.

Description

Technical Field

[0001] This invention relates to the field of underground engineering and tunnel structure waterproofing and drainage technology, and in particular to a drainage device for expansion joints in the floor slab of an open-cut tunnel. Background Technology

[0002] During service, the expansion joints of the bottom slab of open-cut tunnels are affected by temperature differences, differential settlement of the foundation, and load changes, resulting in continuous opening, closing, and displacement of the joints.

[0003] Current methods for waterproofing and drainage of expansion joints in the floor slab of open-cut tunnels mostly rely on a single waterstop or surface sealant to prevent water seepage. The problems exposed by this method in engineering practice are as follows:

[0004] 1) The sealant at the joint is prone to cracking or detachment under repeated tension and pressure, causing water to seep in along the joint.

[0005] 2) After water enters the seam, there is no stable drainage channel, which can easily cause local water accumulation and water pressure buildup, which in turn seeps out from the weak point.

[0006] 3) For longer expansion joints, the joints between sections often become weak points for leakage.

[0007] 4) Once the waterproof layer or pre-embedded waterstop under the bottom slab of the open-cut tunnel fails, it will be basically impossible to control water seepage at the expansion joint. Long-term operation may affect road traffic safety and reduce the durability of the pavement.

[0008] Therefore, how to achieve a combination of seam protection, deformation adaptation, composite sealing, and effective waterproofing is a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0009] The purpose of this invention is to provide a drainage device for the expansion joint of the bottom slab of an open-cut tunnel, which can combine joint protection, deformation adaptation, composite sealing and effective drainage.

[0010] To solve the above-mentioned technical problems, the present invention provides a drainage device for expansion joints in the floor slab of an open-cut tunnel. The drainage device includes: a receiving groove, which is pre-set on the floor slab and extends along the length of the expansion joint, spanning the expansion joint; a bearing member, which is arranged along the length of the expansion joint, spanning the expansion joint within the receiving groove, and whose side facing the bottom of the receiving groove forms a water collection channel with the bottom of the receiving groove; wherein the bearing member has opposing first and second sides, the first side being fixed to the bottom of the receiving groove on one side of the expansion joint, and the second side overlapping the bottom of the receiving groove; a deformation buffer seal, which fills a reserved space between the second side of the bearing member and the corresponding side wall of the receiving groove, so as to elastically deform within the space to maintain continuous sealing when the expansion joint is repeatedly opened and closed; and a drain pipe, one end of which is connected to the water collection channel, and the other end for draining the liquid collected in the water collection channel.

[0011] Optionally, in the aforementioned drainage device for expansion joints in the open-cut tunnel floor, a fixed area is formed between the first side of the bearing member and the corresponding side of the receiving groove wall; an elastic deformation area is formed between the second side of the bearing member and the corresponding side of the receiving groove wall.

[0012] Optionally, in the aforementioned drainage device for expansion joints in the open-cut tunnel floor, the fixed area is formed by filling the space between the first side of the bearing member and the corresponding side of the receiving groove wall with high-strength grout; the elastic deformation area is formed by providing the deformation buffer seal between the second side of the bearing member and the corresponding side of the receiving groove wall.

[0013] Optionally, in the aforementioned drainage device for expansion joints in the open-cut tunnel floor, the supporting member is a channel steel with an inverted arrangement.

[0014] Optionally, in the aforementioned drainage device for expansion joints in the open-cut tunnel floor, the deformation buffer seal includes: a sealing layer, a buffer layer, and a limiting layer; the three are arranged sequentially along the horizontal direction from the second side of the bearing member toward the corresponding groove wall of the receiving groove.

[0015] Optionally, in the aforementioned drainage device for expansion joints in the open-cut tunnel floor, the sealing layer is an elastic sealant layer, the buffer layer is a foamed polyethylene buffer layer, and the limiting layer is a high-strength grouting material layer.

[0016] Optionally, the drainage device for the expansion joint of the open-cut tunnel floor slab further includes a friction-reducing layer disposed on the top of the bearing member.

[0017] Optionally, in the aforementioned drainage device for the expansion joint of the open-cut tunnel floor, the friction-reducing layer covers part of the top of the load-bearing member.

[0018] Optionally, in the aforementioned drainage device for expansion joints in the open-cut tunnel floor, the friction-reducing layer is a low-friction coefficient material layer.

[0019] Optionally, in the aforementioned drainage device for expansion joints in the floor slab of an open-cut tunnel, a drainage hole is provided on the second side of the bearing member, and the drainage pipe is connected to the water collection channel through the drainage hole. The drainage device for expansion joints in the floor slab of an open-cut tunnel provided by this invention has at least the following beneficial effects:

[0020] 1) By filling the reserved space between the second side of the bearing member and the corresponding side wall of the receiving groove with a deformation buffer seal, the deformation buffer seal can deform together when the expansion joint is repeatedly tensioned or compressed, and is not prone to debonding or cracking, and can adapt to repeated deformation.

[0021] 2) When the waterproof layer or embedded waterstop at the bottom of the base plate loses its water-stopping function, the seepage in the expansion joint can be collected and discharged in time based on the drainage path formed by the water collection channel and the drainage pipe, avoiding water accumulation and pressure buildup, realizing the orderly drainage of seepage, without affecting the road structure, and can make up for the problem of the failure of the lower waterproofing.

[0022] 3) The device based on the present invention can significantly reduce the number of leakage repairs and related costs during operation; and can extend the service life of the road surface. Because there is no water accumulation and continuous water pressure in the joint, the aging rate of the sealing material is slowed down, and the road surface is protected from water seepage or freeze-thaw damage.

[0023] 4) The friction-reducing layer effectively reduces the frictional resistance between the load-bearing components and the upper pavement layer, preventing road surface cracks caused by stress concentration. Attached Figure Description

[0024] The above and other objects, features and advantages of this disclosure will become more apparent from the accompanying drawings, in which like reference numerals generally denote like parts.

[0025] Figure 1 This is a schematic diagram of the longitudinal section at the expansion joint of the bottom slab when the drainage device for the expansion joint of the bottom slab of an open-cut tunnel is applied during construction in one embodiment of the present invention.

[0026] Figure 2 This is a top view of the expansion joint of the bottom slab when the drainage device for the expansion joint of the open-cut tunnel bottom slab is applied during construction in one embodiment of the present invention.

[0027] Figure 3 This is a schematic cross-sectional view of the expansion joint of the bottom slab when the drainage device for the expansion joint of the open-cut tunnel bottom slab is applied during construction in one embodiment of the present invention.

[0028] Figure 4This is a schematic diagram of the drainage pipe extending into the drainage ditch during the construction and application of the drainage device for the expansion joint of the open-cut tunnel floor in one embodiment of the present invention.

[0029] In the picture:

[0030] 1-Base plate; 2-Expansion joint; 3-Accommodation groove; 4-Bearing component; 5-Base plate reinforcement; 6-Limiting layer; 7-Sealing layer; 8-Buffer layer; 9-Polyurethane sealant; 10-Friction-reducing layer; 11-Water collection channel; 12-Drainage pipe; 13-Drainage ditch; 16-Concrete pavement layer; 17-Road surface layer; 19-Side ditch concrete strip. Detailed Implementation

[0031] The following detailed description, in conjunction with the accompanying drawings and specific embodiments, provides a further detailed explanation of the drainage device for expansion joints in the floor slab of an open-cut tunnel according to the present invention. The advantages and features of the present invention will become clearer from the following description and claims. It should be noted that the drawings are all in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the illustration of the embodiments of the present invention.

[0032] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, illustrating only the basic structure of the invention, and therefore only show the components relevant to the invention.

[0033] In the description of the invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the invention 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. Therefore, they should not be construed as limitations on the invention.

[0034] Furthermore, the terms "first" and "second" are used 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 as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0035] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; 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; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0036] Please refer to Figures 1 to 4 The drainage device for the expansion joint of the cut-and-cover tunnel floor slab includes: a receiving groove 3, a bearing member 4, a deformation buffer seal body, and a drainage pipe 12. The receiving groove 3 is pre-installed on the floor slab 1, extending along the length of the expansion joint and spanning it. The bearing member 4 is arranged along the length of the expansion joint 2, spanning the expansion joint 2 within the receiving groove 3, and its side facing the bottom of the receiving groove 3 forms a water collection channel 11 with the bottom of the receiving groove 3. The bearing member 4 has opposing first and second sides. The first side of the container is fixed to the bottom of the container 3 on one side of the expansion joint 2, and the second side overlaps the bottom of the container 3; the deformation buffer seal fills the reserved space between the second side of the bearing member 4 and the corresponding side wall of the container 3, so that when the expansion joint 2 is repeatedly opened and closed, it undergoes elastic deformation in the space to maintain continuous sealing; one end of the drain pipe 12 is connected to the water collection channel 11, and the other end is used to discharge the liquid collected by the water collection channel 11, which is finally connected to the drain ditch 13.

[0037] The drainage device for expansion joints in open-cut tunnels of the present invention does not rely solely on water stopping, but guides, collects and drains seepage water in an orderly manner while stopping water, so that the expansion joint can maintain a stable drainage capacity even when it is open, closed or misaligned, and minimizes the adverse effects of seepage on the road structure and driving safety.

[0038] Specifically, a fixing zone is formed between the first side of the bearing member 4 and the corresponding wall of the receiving groove 3; an elastic deformation zone is formed between the second side of the bearing member 4 and the corresponding wall of the receiving groove 3. The fixing zone is formed by filling the space between the first side of the bearing member 4 and the corresponding wall of the receiving groove 3 with high-strength grout. The high-strength grout solidifies into a whole with the outer wall of the first side of the bearing member and the corresponding wall of the receiving groove 3 in the fixing zone, forming a rigid anchor to anchor the first side of the bearing member 4, i.e., the first side serves as the fixing end. Here, the end of the first side of the bearing member is welded to the bottom plate reinforcement and fixed with high-strength grout to form a stable load-bearing base. The elastic deformation zone is formed by setting the deformation buffer seal between the second side of the bearing member 4 and the corresponding wall of the receiving groove 3.

[0039] A drainage hole is provided on the second side of the bearing member 4. The drain pipe 12 is connected to the water collection channel 11 through the drainage hole, and the seepage water in the water collection channel 11 flows into the drain pipe through the drainage hole. When the joint of the expansion joint 2 is not sealed properly or the waterproof layer or waterstop at the bottom of the base plate fails, a small amount of seepage water will enter the water collection channel 11, preventing water accumulation and pressure buildup in the joint. Drainage holes are provided at appropriate positions along the length of the bearing member 4 and lead to the drain pipe 12, so that the collected water can be discharged outward. This effectively addresses the situation where seepage cannot be controlled after the waterproof layer at the bottom of the base plate fails, and then surges upward, affecting the road surface.

[0040] Here, the function of the support member 4 is as follows:

[0041] 1) Tie the bottom plate structure on both sides of the expansion joint to control the relative displacement caused by uneven settlement and temperature changes.

[0042] 2) It uses its rigidity to bear the load of the upper traffic vehicle, preventing the joint area from being damaged under repeated loads; as a simply supported beam or continuous beam spanning above the expansion joint, it directly transfers the dynamic load of the upper traffic vehicle to the large base plate on both sides, preventing the expansion joint from collapsing due to uneven stress.

[0043] 3) A water collection channel is formed by the lower edge and the expansion joint of the base plate.

[0044] Preferably, in this embodiment, the bearing member 4 is a channel steel with an inverted design. It is understood that the bearing member 4 can also have a similar cross-section (such as U-shaped steel or C-shaped steel). More preferably, the channel steel is a No. 5 ordinary channel steel with a cross-sectional dimension of h=50 mm and b=37 mm. The first side of the channel steel is connected to the reinforcing steel of the base plate structure by welding and is then filled with high-strength grout to form a fixed end.

[0045] For further details, please refer to... Figures 2 to 4 The drainage pipe 12 can be a steel pipe or a PPR pipe. The connection between the drainage pipe 12 and the support member 4 is relatively convenient. The first connection method is as follows: the support member 4 is perforated → the drainage pipe 12 is inserted into the perforation → the pipe is fixed with sealant around the perimeter of the structure → the drainage pipe 12 is installed along a pre-set path to the drainage ditch 13 located within the concrete strip 19 of the side ditch → the drainage pipe 12 is fixed to the concrete surface of the base slab at a certain distance using clamps. The second connection method uses welding. Specifically: the end of the channel steel (during the side connection stage, a hole needs to be made on the side of the channel steel and welded to the drainage pipe) is directly welded to the drainage pipe → the other end of the drainage pipe extends into the drainage ditch → the pipe opening is downstream of the drainage ditch. The drainage pipe is arranged along a certain slope, and its outlet connects to the tunnel's lateral drainage ditch. Relying on gravity, the seepage water in the water collection channel 11 is systematically guided into the lateral drainage ditch 13 and finally discharged outside the structure. A filter screen can be installed at the inlet of the drainage pipe to prevent silt blockage.

[0046] The function of the drainage pipe 12 is to provide a stable drainage path for seepage, preventing water from stagnating near the expansion joint for a long time, thereby protecting the durability of the road pavement and driving safety.

[0047] For further details, please refer to... Figure 1 and Figure 2 The deformation buffer seal includes a sealing layer 7, a buffer layer 8, and a limiting layer 6; these three layers are arranged horizontally, starting from the second side of the support member 4 and moving towards the corresponding wall of the receiving groove 3. In other words, the three layers are arranged sequentially from near to far along the second side of the support member 4, with the sealing layer adjacent to the second side of the support member 4 and the filling layer being the furthest away. All three layers are arranged step-by-step along the direction of joint deformation. Here, the limiting layer 6 is formed by filling with high-strength grout, and its function is to set the deformation limit and provide final support.

[0048] Specifically, the sealing layer 7 is an elastic sealant layer, the buffer layer 8 is a foamed polyethylene buffer layer, and the limiting layer 6 is a high-strength grout layer. The elastic sealant is placed against the channel steel to seal surface water; the foamed polyethylene is placed in the middle to absorb deformation during compression and opening of the joint and to act as an isolation layer; the high-strength grout is placed on the outermost side to provide support; multiple seals are formed along the deformation direction of the joint, while also possessing a certain displacement compensation capability. The three layers together constitute multiple seals, which can maintain continuous sealing even when the joint is repeatedly opened and closed, and are not prone to detachment or cracking, thus solving the problem of failure due to displacement fatigue when conventional single-layer sealant is used.

[0049] Preferably, the drainage device for the expansion joint of the open-cut tunnel floor slab further includes: a friction-reducing layer 10, disposed on the top of the bearing member 4, for reducing interfacial friction and stress concentration during the opening and closing deformation process.

[0050] Preferably, the anti-friction layer 10 covers a portion of the top of the carrier 4. Preferably, as... Figure 1 As shown, in order to prevent the concrete pavement layer 16 located on top of the bearing member 4 from being pulled and damaged in order to accommodate the deformation of the bearing member 4, the friction-reducing layer 10 only needs to cover a part of the bearing member 4, ensuring that the bearing member 4 deforms within the coverage area. The friction-reducing layer 10 provides a sliding interface for the expansion joint displacement, so as to reduce the interface friction and stress concentration during the opening and closing deformation process of the expansion joint.

[0051] In this embodiment, the friction-reducing layer 10 is a low-friction coefficient material layer. The low-friction slip layer is composed of polytetrafluoroethylene (PTFE) film or low-density polyethylene (LDPE) sheet. In this embodiment, the low-friction slip layer is preferably a PTFE plate with cross-sectional dimensions of h=3mm and b=100mm. Its main function is to reduce the sliding friction resistance between the load-bearing member 4 and the upper concrete pavement layer 16, and to prevent relative slippage between the concrete pavement layer and the load-bearing member when the expansion joint 2 is under tension or compression, thus preventing local stress concentration that could lead to cracking of the pavement layer 17.

[0052] To facilitate understanding of the drainage device for expansion joints in open-cut tunnel floor slabs of the present invention, the following detailed description is provided in conjunction with its application and construction process. The specific steps are as follows:

[0053] Please refer to the following during construction: Figure 1 First, a receiving groove 3 is reserved above the expansion joint 2 of the base plate 1. The bearing member 4 is placed into the receiving groove 3 and positioned. The base plate steel bars 5 are welded to the bearing member 4, and the fixed area is filled with high-strength grout to establish a stable stress area. On the movable side, a deformation buffer seal is constructed (i.e., the sealing layer 7, the foamed polymer buffer layer 8, and the limiting layer 6 are constructed in sequence to form a compressible, recoverable, and continuously sealable elastic deformation zone).

[0054] A thin PTFE plate is installed above the bearing member 4 as a friction-reducing layer 10 to serve as a low-friction interface, and is fixed with double-sided tape to prevent debris from entering the gap during wet operations. A water collection channel 11 is formed between the bearing member 4 and the upper part of the expansion joint 2 of the base plate 1, connected to a drainage pipe 12 through a drain hole, and then connected to a drainage ditch 13. The drainage pipe 12 is set along the slope to achieve gravity drainage. During operation, the expansion joint drainage device of the cut-and-cover tunnel base plate first seals the opening of the expansion joint 2 with polyurethane sealant 9 to block external water; a small amount of seeping water is collected in the water collection channel 11 at the lower part of the bearing member 4 and then discharged through the drainage pipe 12 into the drainage ditch 13, thus achieving a coordinated and unified system of water stopping, drainage, flow guidance, drainage, and pressure relief.

[0055] The present invention has the following advantages:

[0056] 1) By filling the reserved space between the second side of the bearing member and the corresponding side wall of the receiving groove with a deformation buffer seal, the deformation buffer seal can deform together when the expansion joint is repeatedly tensioned or compressed, and is not prone to debonding or cracking, and can adapt to repeated deformation.

[0057] 2) When the waterproof layer or embedded waterstop at the bottom of the base plate loses its water-stopping function, the seepage in the expansion joint can be collected and discharged in time based on the drainage path formed by the water collection channel and the drainage pipe, avoiding water accumulation and pressure buildup, realizing the orderly drainage of seepage, without affecting the road structure, and can make up for the problem of the failure of the lower waterproofing.

[0058] 3) The device based on the present invention can significantly reduce the number of leakage repairs and related costs during operation; and can extend the service life of the road surface. Because there is no water accumulation and continuous water pressure in the joint, the aging rate of the sealing material is slowed down, and the road surface is protected from water seepage or freeze-thaw damage.

[0059] 4) The friction-reducing layer effectively reduces the frictional resistance between the load-bearing components and the upper pavement layer, preventing road surface cracks caused by stress concentration.

[0060] The above description is merely a description of preferred embodiments of the present invention and is not intended to limit the scope of the present invention in any way. Any changes or modifications made by those skilled in the art based on the above disclosure shall fall within the protection scope of the claims.

Claims

1. A drainage device for expansion joints in the floor slab of an open-cut tunnel, characterized in that, include: The receiving groove (3) is pre-set on the base plate (1), extends along the length direction of the expansion joint, and spans the expansion joint; The support member (4) is arranged along the length of the expansion joint (2), spanning the expansion joint (2) within the receiving groove (3), and its side facing the bottom of the receiving groove (3) forms a water collection channel (11) with the bottom of the receiving groove (3); wherein, The bearing member (4) has a first side and a second side opposite to each other. Its first side is fixed to the bottom of the receiving groove (3) on one side of the expansion joint (2), and its second side overlaps the bottom of the receiving groove (3). A deformable buffer seal is filled in the reserved space between the second side of the bearing member (4) and the corresponding side wall of the receiving groove (3) so that when the deformation joint (2) is repeatedly opened and closed, it undergoes elastic deformation in the space to maintain a continuous seal. The drain pipe (12) has one end connected to the water collection channel (11) and the other end used to drain the liquid collected by the water collection channel (11).

2. The drainage device for the expansion joint of the open-cut tunnel floor as described in claim 1, characterized in that, The first side of the support member (4) and the corresponding side of the receiving groove (3) form a fixed area; the second side of the support member (4) and the corresponding side of the receiving groove (3) form an elastic deformation area.

3. The drainage device for the expansion joint of the open-cut tunnel floor slab as described in claim 2, characterized in that, The fixed area is formed by filling the space between the first side of the bearing member (4) and the corresponding side of the receiving groove (3) with high-strength grout; the elastic deformation area is formed by setting the deformation buffer seal between the second side of the bearing member (4) and the corresponding side of the receiving groove (3).

4. The drainage device for the expansion joint of the open-cut tunnel floor as described in claim 1, characterized in that, The bearing member (4) is a channel steel with an inverted arrangement.

5. The drainage device for the expansion joint of the open-cut tunnel floor as described in claim 1, characterized in that, The deformable buffer seal includes a sealing layer (7), a buffer layer (8), and a limiting layer (6); the three are arranged in sequence along the horizontal direction from the second side of the bearing member (4) toward the corresponding groove wall of the receiving groove (3).

6. The drainage device for the expansion joint of the open-cut tunnel floor slab as described in claim 5, characterized in that, The sealing layer (7) is an elastic sealant layer, the buffer layer (8) is a foamed polyethylene buffer layer, and the limiting layer (6) is a high-strength grouting material layer.

7. The drainage device for the expansion joint of the open-cut tunnel floor as described in claim 1, characterized in that, Also includes: A friction-reducing layer (10) is disposed on the top of the support member (4).

8. The drainage device for the expansion joint of the open-cut tunnel floor slab as described in claim 7, characterized in that, The friction-reducing layer (10) covers part of the top of the carrier (4).

9. The drainage device for the expansion joint of the open-cut tunnel floor as described in claim 7, characterized in that, The friction-reducing layer (10) is a low-friction coefficient material layer.

10. The drainage device for the expansion joint of the open-cut tunnel floor slab as described in any one of claims 1 to 9, characterized in that, The second side of the support member (4) is provided with a drain hole, and the drain pipe (12) is connected to the water collection channel (11) based on the drain hole.

Images