Highway tunnel anti-permeation structure

Abstract

The invention belongs to the technical field of highway tunnel permeation prevention, and particularly relates to a highway tunnel permeation prevention structure which comprises a tunnel and a permeation prevention assembly, the permeation prevention assembly comprises a concrete reinforcing layer, supporting steel plates are arranged in the concrete reinforcing layer in the radial direction of the concrete reinforcing layer at equal intervals, and prefabricated concrete layers are arranged on the two sides of the supporting steel plates; the prefabricated concrete layers form an arc-shaped tunnel structure matched with the concrete reinforcing layer, isolation layers are formed between the prefabricated concrete layers and the concrete reinforcing layer, and waterproof materials are arranged between the isolation layers; a plurality of drainage grooves are formed in the part, located in the isolation layer, of the supporting steel plate in the length direction of the tunnel at equal intervals in a penetrating mode, an alarm assembly is arranged in the end, located in the tunnel, of the supporting steel plate and used for judging the water leakage position, and drainage holes communicating with the isolation layer are symmetrically formed in the bottom ends of the two sides of the anti-permeation assembly. The service life of the waterproof material can be prolonged, so that the waterproof effect of the tunnel is ensured, and the water leakage problem can be found in time.

Description

Technical Field

[0001] The invention belongs to the technical field of highway tunnel anti-seepage, and in particular relates to a highway tunnel anti-seepage structure. Background Art

[0002] Waterproofing of highway tunnels is an important part of ensuring the safety and service life of tunnel structures. It is crucial to protecting tunnel structures, increasing service life, and ensuring driving safety. Once water seepage occurs in a tunnel, it will directly affect the quality of the main structure of the project and its safety in use, and may cause damage to the internal facilities of the tunnel, slippery road surfaces that affect driving safety, and other issues. Therefore, waterproofing work must be given high attention during the design, construction, and maintenance of tunnels.

[0003] A Chinese utility model patent with authorization announcement number CN216379666U and authorization announcement date 2022.04.26 discloses an anti-seepage structure for a highway tunnel, including a tunnel main body, an anti-seepage unit fixedly connected to the interior of the tunnel main body; when cracks appear in the tunnel main body, seepage water needs to pass through the anti-seepage unit to re-enter the tunnel channel, and multiple protections are provided by the first waterproof isolation layer, the second waterproof blocking layer and the third waterproof isolation layer to block the penetration of water flow. When cracks appear under the action of external force, the seepage water enters the gap between the first waterproof isolation layer, the second waterproof blocking layer and the third waterproof isolation layer and contacts the blocking layer, and the blocking layer solidifies when it encounters water to block the cracks. The blocking layer is divided into multiple sections by the first waterproof membrane and the second waterproof isolation layer, and the seepage water around the cracks can also be blocked again to improve the overall anti-seepage effect of the tunnel main body and make the interior of the tunnel main body safer. However, in the anti-seepage structure of the highway tunnel, the anti-seepage inside the tunnel can only be waterproofed inside the top of the tunnel, and there are concrete layers on both sides of the waterproof material. Since the concrete layer is relatively thick, it will cause squeezing damage to the waterproof material and affect the waterproof effect; secondly, there is only one layer of waterproofing inside the top of the tunnel. If a leak occurs, it is not easy to carry out internal repairs, and it is difficult to determine the location of the leak. Moreover, if there is a leak in the tunnel, the water leaked from the leak point cannot be discharged in time, which will further expand the scope of impact and increase the risk of leakage in other parts. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide an anti-seepage structure for a highway tunnel in view of the deficiencies in the prior art. The present invention can increase the service life of the waterproof material, thereby ensuring the waterproof effect of the tunnel, and can promptly detect leakage problems to prevent the leakage from worsening.

[0005] This solution is achieved through the following technical measures: a highway tunnel anti-seepage structure, including a highway tunnel body, a tunnel is opened in the highway tunnel body, and an anti-seepage component is arranged above the tunnel; the anti-seepage component includes a concrete reinforcement layer, the concrete reinforcement layer is in contact with the inner wall of the tunnel, support steel plates are arranged in the concrete reinforcement layer at equal intervals along its radial direction, one end of the support steel plate is located in the concrete reinforcement layer, and the other end extends to the outside of the concrete reinforcement layer, precast concrete layers are arranged on both sides of one end of the support steel plate away from the concrete reinforcement layer, and a plurality of the precast concrete layers form an arc-shaped tunnel structure adapted to the concrete reinforcement layer, an isolation layer is formed between the precast concrete layer and the concrete reinforcement layer, and a waterproof material is arranged between the isolation layers; The portion of the support steel plate located within the isolation layer is provided with a number of drainage grooves at equal intervals along the direction of the tunnel; an alarm component is provided at one end of the support steel plate located within the tunnel to determine the location of the water leakage; drainage holes connected to the isolation layer are symmetrically provided at the bottom ends of both sides of the anti-permeability component.

[0006] Preferably, the waterproof material includes a waterproof coating, which is evenly applied to the lower side wall of the concrete reinforcement layer, a first waterproof membrane is laid on the waterproof coating, and a second waterproof membrane is laid on the surface of the precast concrete layer opposite to the concrete reinforcement layer.

[0007] Preferably, the waterproof coating layer adopts a penetrating waterproofing agent material, which is used to penetrate into the concrete reinforcement layer to form insoluble crystals.

[0008] Preferably, the interior of the concrete reinforcement layer is reinforced with a corrugated steel structure to increase the support of the concrete reinforcement layer.

[0009] Preferably, the precast concrete layers on both sides of the supporting steel plate are detachably connected, and the gaps formed between the supporting steel plate and the precast concrete layers on both sides are filled with sealing and waterproof materials.

[0010] Preferably, the upper surface of the second waterproof membrane is flush with the bottom end of the drainage groove.

[0011] Preferably, a leakage hole is opened on the side of the support steel plate opposite to the drainage groove, the center lines of the leakage holes at corresponding positions on two adjacent support steel plates are cocircular, and the drainage groove and the leakage hole form a triangular structure.

[0012] Preferably, two adjacent supporting steel plates and the precast concrete layer therebetween form a detection unit, a water storage hole is provided in the supporting steel plate at the leakage hole and penetrates radially through the tunnel, and the alarm component is sealed at one end of the water storage hole away from the leakage hole.

[0013] Preferably, the alarm component includes a mounting tube, wherein the mounting tube is fixedly connected to an end of the water storage hole away from the leakage hole, an alarm light is fixedly arranged in the end of the mounting tube away from the leakage hole, the alarm light is exposed in the tunnel, a button battery is arranged on the end of the alarm light located in the mounting tube, one pole of the alarm light is in contact with and electrically connected to one pole of the button battery, an electrically connecting spring is arranged on the side of the end of the alarm light located in the mounting tube, one end of the electrically connecting spring is electrically connected to the other pole of the alarm light, and the other end is in an arc-shaped structure and is located directly above the other pole of the button battery, and the alarm light emits light after the electrically connecting spring is in contact with the other pole of the button battery.

[0014] Preferably, the electrically connecting spring sheet is bendable and has a certain elasticity, and a pressing rod is slidably connected to the end of the mounting tube away from the alarm light, and one end of the pressing rod located in the mounting tube is located directly above the electrically connecting spring sheet and fits with the electrically connecting spring sheet, and the other end of the pressing rod extends to the outside of the mounting tube to form an extrusion portion, and a waterproof rubber telescopic sleeve is provided on the outer sleeve of the mounting tube, and the top inner wall of the waterproof rubber telescopic sleeve fits with the extrusion portion of the pressing rod, so as to seal the mounting tube.

[0015] Beneficial effects of the present invention: 1. In the anti-seepage structure of the highway tunnel, by setting a concrete reinforcement layer combined with the supporting steel plate of the built-in corrugated steel structure, the support of the tunnel is enhanced, the pressure of the inner wall of the tunnel on the waterproof material is effectively dispersed, and the waterproof material is prevented from being damaged by extrusion, which is beneficial to protect the waterproof material and prolong its service life, thereby ensuring the waterproof effect of the tunnel; 2. In the anti-seepage structure of the highway tunnel, a removable precast concrete layer is installed on both sides of the supporting steel plate to form an arc-shaped structure that matches the inner wall of the tunnel. It is designed to facilitate the removal and replacement of the precast concrete layer when necessary, which provides convenience for the later maintenance of the tunnel. The easy maintenance feature is conducive to timely detection and repair of water leakage problems and prevent the leakage from worsening; 3. In the anti-seepage structure of the highway tunnel, an isolation layer is formed between the precast concrete layer and the concrete reinforcement layer through the setting of an isolation layer and multiple waterproof materials, and waterproof materials are set on both sides of the isolation layer. The setting of multiple waterproof materials improves the waterproof performance of the tunnel, which is conducive to enhancing the waterproof ability of the tunnel and reducing the risk of water leakage; 4. In the anti-seepage structure of the highway tunnel, drainage grooves and leakage holes are set on the supporting steel plate through the combination of drainage grooves and alarm components, so that the accumulated water is guided to the drainage holes for discharge, avoiding the accumulation of accumulated water. At the same time, an alarm component is set in the water storage hole. When the accumulated water reaches a certain level, the alarm light is triggered to light up, which is convenient for timely discovery of the leakage position, improves the accuracy of leakage detection, is conducive to quickly locating the leakage point, shortens the maintenance time, and reduces the maintenance cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the overall structure of the present invention; Figure 2 for Figure 1 The enlarged view of point A in the middle; Figure 3 It is a schematic cross-sectional structural diagram of the anti-permeation component in the present invention; Figure 4 for Figure 3 The enlarged view of point B in the middle; Figure 5 It is a schematic diagram of the local structure of the precast concrete layer in the present invention; Figure 6 It is a structural schematic diagram of the supporting steel plate in the present invention; Figure 7 It is a schematic diagram of the cross-sectional structure of the supporting steel plate in the present invention; Figure 8 It is a schematic cross-sectional structural diagram of the alarm component in the present invention.

[0017] In the figure: 1. highway tunnel body; 2. anti-seepage component; 3. drainage hole; 4. concrete reinforcement layer; 5. precast concrete layer; 6. supporting steel plate; 7. isolation layer; 8. drainage trough; 9. waterproof coating; 10. first waterproof membrane; 11. second waterproof membrane; 12. leakage hole; 13. water storage hole; 14. alarm component; 141. alarm light; 142. installation tube; 143. button battery; 144. electrical connection spring; 145. pressing rod; 146. waterproof rubber telescopic sleeve. DETAILED DESCRIPTION

[0018] In order to clearly illustrate the technical features of this solution, this solution is described below through specific implementation methods and in conjunction with the accompanying drawings.

[0019] The highway tunnel anti-seepage structure comprises a highway tunnel body 1, a tunnel is opened in the highway tunnel body 1, and an anti-seepage component 2 is arranged above the tunnel.

[0020] The anti-permeability component 2 includes a concrete reinforcement layer 4, which is in contact with the inner wall of the tunnel. Moreover, the interior of the concrete reinforcement layer 4 is reinforced with a corrugated steel structure to increase the support of the concrete reinforcement layer 4. Support steel plates 6 are arranged at equal intervals along the radial direction of the concrete reinforcement layer 4. One end of the support steel plate 6 is located in the concrete reinforcement layer 4 and the other end extends to the outside of the concrete reinforcement layer 4. Precast concrete layers 5 are arranged on both sides of the end of the support steel plate 6 away from the concrete reinforcement layer 4. The precast concrete layers 5 on both sides of the support steel plate 6 are detachably connected, and each precast concrete layer 5 forms an arc-shaped tunnel structure that matches the concrete reinforcement layer 4. Specifically, the installation is performed through the pre-opened holes on the support steel plate 6 and the precast concrete layer 5. After the precast concrete layer 5 is fully installed, an arc structure that matches the shape of the concrete reinforcement layer 4 (i.e., the inner wall of the tunnel) will be formed, and the gaps formed between the support steel plate 6 and the precast concrete layers 5 on both sides are filled with sealing and waterproof materials to prevent the subsequent detection errors caused by water leakage from the gap between the precast concrete layer 5 and the support steel plate 6 in the future. The role of the precast concrete layer 5 is to play the role of supporting the second layer in the tunnel. At the same time, it is easy to disassemble, which provides convenience for later maintenance and can further improve the anti-seepage effect.

[0021] An isolation layer 7 is formed between the precast concrete layer 5 and the concrete reinforcement layer 4, and a waterproof material is arranged between the upper and lower sides of the isolation layer 7; the waterproof material includes a waterproof coating 9, which is evenly applied to the lower side wall of the concrete reinforcement layer 4, and a first waterproof roll 10 is laid on the waterproof coating 9. The first waterproof roll 10 plays the role of a second waterproof layer to prevent the concrete reinforcement layer 4 from cracking due to external force and causing water seepage. A second waterproof roll 11 is laid on the surface of the side of the precast concrete layer 5 opposite to the concrete reinforcement layer 4. The waterproof coating 9 adopts a penetrating waterproofing agent material, such as an inorganic penetrating waterproofing agent such as an inorganic permeable liquid DPS, which is used to penetrate into the concrete reinforcement layer 4 to form insoluble crystals. The waterproof coating 9 can penetrate into the concrete reinforcement layer 4 to form insoluble crystals, which plays a role in further sealing, waterproofing and moisture-proofing the concrete reinforcement layer 4, and the thickness of the concrete reinforcement layer 4 will not be significantly increased due to the application of a layer of waterproof coating 9.

[0022] The portion of the supporting steel plate 6 located within the isolation layer 7 is provided with a plurality of drainage grooves 8 at equal intervals along the length direction of the tunnel. An alarm component 14 is provided at one end of the supporting steel plate 6 located within the tunnel. The alarm component 14 is used to determine the location of the water leakage. Drainage holes 3 connected to the isolation layer 7 are symmetrically provided at the bottom ends of both sides of the anti-permeability component 2. When the precast concrete layer 5 is installed, the upper surface of the second waterproof membrane 11 is made flush with the bottom end of the drainage groove 8.

[0023] A leakage hole 12 is provided on the side of the supporting steel plate 6 opposite to the drainage groove 8, the center lines of the corresponding leakage holes 12 on two adjacent supporting steel plates 6 are cocircular, and the drainage groove 8 and the leakage hole 12 form a triangular structure; the two adjacent supporting steel plates 6 and the precast concrete layer 5 located therebetween form a detection unit, and a water storage hole 13 is provided in the supporting steel plate 6 at the leakage hole 12 and passes through the radial direction of the tunnel, and the alarm component 14 is sealed and arranged at the end of the water storage hole 13 away from the leakage hole 12.

[0024] The alarm assembly 14 includes a mounting tube 142, which is fixedly connected to the end of the water storage hole 13 away from the water leakage hole 12, and an alarm light 141 is fixedly arranged in the end of the mounting tube 142 away from the water leakage hole 12, and the alarm light 141 is exposed in the tunnel, and a button battery 143 is arranged on the end of the alarm light 141 located in the mounting tube 142, and one pole of the alarm light 141 is in contact with and electrically connected to one pole of the button battery 143, and an electrical connection spring 144 is arranged on the side of the end of the alarm light 141 located in the mounting tube 142, and one end of the electrical connection spring 144 is electrically connected to the other pole of the alarm light 141, and the other end is an arc-shaped structure located at the other pole of the button battery 143. At the top, after the electrical connection spring piece 144 is fitted with the other pole of the button battery 143, the alarm light 141 lights up; the electrical connection spring piece 144 is bendable and has a certain elasticity, and a pressing rod 145 is slidably connected to the end of the mounting tube 142 away from the alarm light 141, and one end of the pressing rod 145 located in the mounting tube 142 is located directly above the electrical connection spring piece 144 and fits with the electrical connection spring piece 144, and the other end of the pressing rod 145 extends to the outside of the mounting tube 142 to form an extrusion portion, and the outer cover of the mounting tube 142 is provided with a waterproof rubber telescopic sleeve 146, and the top inner wall of the waterproof rubber telescopic sleeve 146 fits with the extrusion portion of the pressing rod 145, which is used to seal the mounting tube 142.

[0025] A narrow isolation layer 7 is formed between each precast concrete layer 5 and the concrete reinforcement layer 4 through the connection support of the supporting steel plate 6. In this way, the upper and lower layers of the isolation layer 7 are waterproof, and a flowable channel is formed in the middle through the drainage groove 8 and the leakage hole 12. In addition, the precast concrete layer 5 provides a waterproof barrier line through the second waterproof membrane 11 and itself (precast concrete layer 5) for the waterproof layer. Secondly, due to the arc structure of the precast concrete layer 5, if water falls on the second waterproof membrane 11, it will eventually slide onto the supporting steel plate 6, and then the water will be guided to each detection unit through the drainage groove 8 and the leakage hole 12 and finally discharged through the drainage hole 3, which will not cause the accumulation of seepage water; thirdly, compared with the concrete reinforcement layer 4, there is no need to take too many waterproof measures.

[0026] When the concrete reinforcement layer 4 leaks and also damages the first waterproof membrane 10, the water will leak into the isolation layer 7. However, since the isolation layer 7 is divided into multiple detection units by the precast concrete layer 5 and the supporting steel plates 6 on both sides, the water will slide down the supporting steel plates 6 through the second waterproof membrane 11, and then because the drainage groove 8 is in contact with the upper surface of the second waterproof membrane 11, it will eventually enter the drainage groove 8. At this time, the water will slowly flow into the water storage hole 13 through the triangular structure of the drainage groove 8, and the rest of the water will flow out of the leakage hole. 12 flows into the next detection unit, and so on, until it flows into the bottom of the lowest detection unit on both sides, enters the drainage hole 3 and flows out. As water continues to accumulate in the water storage hole 13, the gravity of the water will squeeze the waterproof rubber telescopic sleeve 146, and then the waterproof rubber telescopic sleeve 146 squeezes the pressing rod 145, so that the pressing rod 145 squeezes the electrical connection spring piece 144, causing the electrical connection spring piece 144 to fit with the other pole of the button battery 143, so that the alarm light 141 is turned on, and the alarm light 141 will light up.

[0027] The present invention divides the detection units in the tunnel into two major parts, left and right, along the width direction of the tunnel. If a certain area on one side leaks and causes damage to the first waterproof membrane 10, water will leak into the corresponding detection unit and then flow downward. Therefore, for several detection units on one side, it is only necessary to find the detection unit closest to the vertical line of the tunnel center, and then the leakage position can be roughly determined based on which axial interval of the precast concrete layer 5 has the alarm light 141 lit. After that, the precast concrete layer 5 can be removed for later maintenance.

[0028] Secondly, if multiple alarm lights 141 light up, it can be judged based on the locations of the multiple alarm lights 141. If they are located on the same vertical plane, it can be determined that there is a water leak at one location. If the lights are not located on a vertical plane, then based on the above judgment process, the detection units closest to the vertical line of the tunnel center in each area can be found and disassembled for maintenance.

[0029] By arranging a number of supporting steel plates 6 on the concrete reinforcement layer 4, and then installing precast concrete layers 5 on both sides of the supporting steel plates 6, an isolation layer 7 is formed between the precast concrete layer 5 and the concrete reinforcement layer 4, so as to facilitate multiple waterproofing in the isolation layer 7, and the existence of the isolation layer 7 will not cause squeezing damage to the waterproof material, which is conducive to the role of the waterproof material; secondly, the precast concrete layers 5 detachably connected by the supporting steel plates 6, combined with the alarm component 14 arranged at the bottom of the supporting steel plates 6, can determine the specific location of the leakage if the first waterproof membrane 10 is damaged, so as to disassemble the precast concrete layer 5 for maintenance; finally, the remaining water can be discharged in time through the drainage groove 8 and the leakage hole 12 on the supporting steel plate 6 to prevent large-scale water seepage.

[0030] Technical features not described in the present invention can be implemented by existing technologies and will not be described in detail here. The present invention is not limited to the above specific embodiments, and changes, modifications, additions or substitutions made by ordinary technicians in the field within the essential scope of the present invention should also fall within the protection scope of the present invention.

Claims

1. A highway tunnel anti-seepage structure, comprising a highway tunnel body (1), wherein a tunnel is opened in the highway tunnel body (1), and an anti-seepage component (2) is arranged above the tunnel, characterized in that: The anti-permeability component (2) comprises a concrete reinforcement layer (4), the concrete reinforcement layer (4) being in contact with the inner wall of the tunnel, support steel plates (6) being arranged in the concrete reinforcement layer (4) at equal intervals along its radial direction, one end of the support steel plate (6) being located in the concrete reinforcement layer (4), and the other end extending outside the concrete reinforcement layer (4), and precast concrete layers (5) being arranged on both sides of one end of the support steel plate (6) away from the concrete reinforcement layer (4), and the plurality of precast concrete layers (5) forming an arc-shaped tunnel structure matching the concrete reinforcement layer (4); An isolation layer (7) is formed between the precast concrete layer (5) and the concrete reinforcement layer (4), and a waterproof material is provided between the isolation layers (7); The portion of the support steel plate (6) located inside the isolation layer (7) is provided with a plurality of drainage grooves (8) at equal intervals along the length direction of the tunnel. An alarm component (14) is provided at one end of the support steel plate (6) located inside the tunnel for determining the location of a water leak. Drainage holes (3) connected to the isolation layer (7) are symmetrically provided at the bottom ends of both sides of the anti-permeability component (2).

2. The highway tunnel anti-seepage structure according to claim 1, characterized in that: The waterproof material comprises a waterproof coating (9), the waterproof coating (9) being evenly applied to the lower side wall of the concrete reinforcement layer (4), a first waterproof coiled material (10) being laid on the waterproof coating (9), and a second waterproof coiled material (11) being laid on the surface of the side of the precast concrete layer (5) opposite to the concrete reinforcement layer (4).

3. The highway tunnel anti-seepage structure according to claim 2, characterized in that: The waterproof coating (9) is made of a permeable waterproofing agent material, which is used to penetrate into the concrete reinforcement layer (4) to form insoluble crystals.

4. The highway tunnel anti-seepage structure according to claim 3, characterized in that: The interior of the concrete reinforcement layer (4) is reinforced with a corrugated steel structure to increase the support of the concrete reinforcement layer (4).

5. The highway tunnel anti-seepage structure according to claim 4, characterized in that: The precast concrete layers (5) on both sides of the supporting steel plate (6) are detachably connected, and the gaps formed between the supporting steel plate (6) and the precast concrete layers (5) on both sides are filled with sealing and waterproof materials.

6. The highway tunnel anti-seepage structure according to claim 5, characterized in that: The upper surface of the second waterproof coiled material (11) is flush with the bottom end of the drainage groove (8).

7. The highway tunnel anti-seepage structure according to claim 6, characterized in that: A water leakage hole (12) is provided on a side of the support steel plate (6) opposite to the drainage groove (8), the center lines of the corresponding water leakage holes (12) on two adjacent support steel plates (6) are cocircular, and the drainage groove (8) and the water leakage hole (12) form a triangular structure.

8. The highway tunnel anti-seepage structure according to claim 7, characterized in that: Two adjacent supporting steel plates (6) and a precast concrete layer (5) located therebetween form a detection unit; a water storage hole (13) is provided in the supporting steel plate (6) at the water leakage hole (12) and penetrates in the radial direction of the tunnel; and the alarm component (14) is sealed and arranged at one end of the water storage hole (13) away from the water leakage hole (12).

9. The highway tunnel anti-seepage structure according to claim 8, characterized in that: The alarm assembly (14) comprises a mounting tube (142), the mounting tube (142) being fixedly connected to one end of the water storage hole (13) away from the water leakage hole (12), an alarm light (141) being fixedly arranged in the one end of the mounting tube (142) away from the water leakage hole (12), the alarm light (141) being exposed in the tunnel, a button battery (143) being arranged on one end of the alarm light (141) located in the mounting tube (142), one pole of the alarm light (141) being connected to the button battery The warning light (141) is provided with an electrically connecting spring sheet (144) on the side of one end of the warning light (141) located in the mounting tube (142); one end of the electrically connecting spring sheet (144) is electrically connected to the other end of the warning light (141); the other end of the electrically connecting spring sheet (144) is in an arc-shaped structure and is located directly above the other end of the button battery (143); after the electrically connecting spring sheet (144) is in contact with the other end of the button battery (143), the warning light (141) emits light.

10. The highway tunnel anti-seepage structure according to claim 9, characterized in that: The electrical connection spring sheet (144) is bendable and has a certain elasticity. A pressing rod (145) is slidably connected to one end of the installation tube (142) away from the alarm light (141). One end of the pressing rod (145) located inside the installation tube (142) is located directly above the electrical connection spring sheet (144) and fits with the electrical connection spring sheet (144). The other end of the pressing rod (145) extends outside the installation tube (142) to form an extrusion portion. The installation tube (142) is provided with a waterproof rubber telescopic sleeve (146) on its outer sleeve. The inner wall of the top end of the waterproof rubber telescopic sleeve (146) fits with the extrusion portion of the pressing rod (145) to seal the installation tube (142).

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