Fastening device for waterproofing membrane end of pile head and fastening method thereof

Abstract

The application relates to the technical field of pile foundation waterproofing, and discloses a fastening device and method for pile head waterproofing coiled material end termination. The device comprises a ring-shaped shell, an elastic inner lining and a dynamic pre-tightening assembly. The ring-shaped shell is formed by splicing and enclosing at least two arc-shaped plates, and the end of each arc-shaped plate is provided with a connecting part. The elastic inner lining is fixed to the inner wall of the ring-shaped shell, and the inner surface is provided with a plurality of sawtooth-shaped protrusions. The dynamic pre-tightening assembly is used for fixing the connecting parts of adjacent arc-shaped plates and applying a pre-tightening force, so that the sawtooth-shaped protrusions press the waterproofing coiled material. There is a gap between the splicing surfaces of the connecting parts, and when the thickness of the waterproofing coiled material changes, the dynamic pre-tightening assembly can adjust the gap and compensate for the radial gap change of the waterproofing coiled material in real time. The device can be sleeved on the pile head, the sawtooth-shaped protrusions are in contact with the waterproofing coiled material, and the dynamic pre-tightening mechanism ensures long-term stable sealing, effectively solves the technical problems that the traditional pile head waterproofing coiled material end termination is prone to loosening and leakage, and improves the waterproofing reliability of the pile foundation.

Description

Technical Field

[0001] This invention relates to a fastening device and method for the termination of waterproof membrane at pile heads, belonging to the field of underground waterproofing engineering technology. Background Technology

[0002] In underground engineering waterproofing construction, the waterproofing treatment at the junction of the pile foundation and the base slab is a critical point. In on-site construction, asphalt-based modified waterproof membranes or polymer flexible waterproof membranes are usually used to waterproof the pile body. However, at the pile head termination point, fixing and sealing the waterproof membrane has always been a technical challenge in engineering practice.

[0003] In existing technologies, such as the patent document with publication number CN215630186U, a waterproof structure for the head of precast piles in basements with high water levels is disclosed. Specifically, it discloses that "the pile head of the precast pile 7 is wrapped with a combined water-stop ring steel sleeve 4 on the outside of the waterproof layer 3," and that "the combined water-stop ring steel sleeve 4 consists of two semi-circular sleeves, secured by galvanized flat iron clamps 5." It uses a "split-type rigid steel sleeve + galvanized flat iron clamp" for mechanical locking. This rigid fastening method can provide a large pre-tightening force during initial installation and has a certain waterproofing effect. However, this rigid fastening structure has the following technical problems in practical engineering applications:

[0004] First, bitumen-based waterproof membranes exhibit viscoelastic properties. Under continuous radial pressure, the bitumen components within the membrane undergo slow plastic flow, leading to a gradual reduction in membrane thickness. Since the circumference of the rigid metal clamp remains constant after the bolts are tightened and cannot automatically adjust with changes in membrane thickness, the preload gradually decreases over time, ultimately causing seal failure between the membrane and the pile.

[0005] Secondly, the inner wall of rigid metal sleeves is usually smooth, and the slippage between them and the waterproof membrane mainly relies on static friction and the membrane's own adhesion. Under the action of groundwater buoyancy or pull-out force generated by backfill settlement, the membrane is prone to slippage downwards, causing damage to the waterproof layer.

[0006] Furthermore, rigid metal structures cannot adapt to the unevenness and ellipticity deviation of the surface of cast-in-place piles in actual engineering projects, which can easily lead to uneven stress gaps in local locations, affecting the sealing effect.

[0007] Therefore, a new technical solution is needed that can adapt to the long-term deformation characteristics of waterproof membranes, automatically maintain a stable preload when the membrane thickness changes, and provide a reliable mechanical anti-slip structure to achieve long-term sealing of the waterproof membrane termination at the pile head. Summary of the Invention

[0008] This invention provides a fastening device and method for the termination of waterproof membrane at pile heads, aiming to solve the problems of sealing failure caused by deformation of waterproof membrane and easy slippage between the sleeve and the waterproof membrane in the prior art.

[0009] To solve the above technical problems, the present invention includes the following technical solutions:

[0010] A fastening device for the termination of waterproof membrane at a pile head, wherein the pile head is connected to a cast-in-place concrete structure and the outer wall of the pile head is covered with waterproof membrane; the fastening device includes an annular outer shell, which is formed by splicing at least two arc-shaped plates, and the ends of the arc-shaped plates are provided with connecting portions; it also includes:

[0011] An elastic inner lining layer is fixed to the inner wall of the annular outer shell, and the inner surface of the elastic inner lining layer is provided with a plurality of serrated protrusions; the annular outer shell is fitted onto the pile head, and the serrated protrusions are in contact with the waterproof membrane.

[0012] The dynamic pre-tightening assembly is used to fix the connection of adjacent arc-shaped plates and apply a pre-tightening force to the connection. The serrated protrusions of the elastic inner lining layer press the waterproof membrane. There is a gap between the splicing surfaces of the connection. When the thickness of the waterproof membrane changes due to deformation, the pre-tightening force of the dynamic pre-tightening assembly can adjust the gap and compensate for the radial gap changes of the waterproof membrane in real time.

[0013] Furthermore, the dynamic pre-tightening assembly includes a fixing member and a pre-tightening member. The fixing member is used to splice and fix the connecting parts of adjacent arc-shaped plates, and the pre-tightening member is used to apply a pre-tightening force to the connecting parts of adjacent arc-shaped plates to bring them closer together.

[0014] Furthermore, the fastener includes bolts and nuts;

[0015] The connecting part is provided with a mounting hole, and one end of the bolt passes through the mounting hole of the connecting part of the adjacent arc-shaped plate and is fixed by a nut;

[0016] The preload is disposed between the head of the bolt and the connecting part or / and between the connecting part and the nut.

[0017] Furthermore, the serrated protrusions are multiple toothed strips distributed in a ring;

[0018] The cross-section of the rack includes an upper tooth surface, an outer tooth surface, and a lower tooth surface. The angle between the upper tooth surface and the outer tooth surface is an acute angle, and the angle between the lower tooth surface and the outer tooth surface is an obtuse angle.

[0019] Furthermore, the angle between the external tooth surface and the vertical plane is 30° to 45°, and the angle between the lower tooth surface and the vertical plane is 80° to 90°.

[0020] Furthermore, the top of the elastic inner liner is provided with an annular sealing groove on the side facing the pile head.

[0021] Accordingly, the present invention also provides a method for fastening the termination of waterproof membrane at pile heads, comprising the following steps:

[0022] Lay the waterproof membrane, turning it upside down along the pile head to the predetermined height;

[0023] The annular outer shell of the fastening device is wrapped around the end of the waterproof membrane. The annular outer shell is fixed by pre-tightening force through the dynamic pre-tightening component. There is a gap between the splicing surfaces of the joint after fixing. The serrated protrusions of the elastic inner lining layer press the waterproof membrane tightly.

[0024] Construct a concrete structure to cover the fastening devices and pile heads;

[0025] When the thickness of the waterproof membrane changes due to deformation, the pre-tightening force of the dynamic pre-tightening component can adjust the gap between the splicing surfaces of the joint and compensate for the radial gap changes of the waterproof membrane in real time.

[0026] Furthermore, the pre-tightening force enables the serrated protrusions of the elastic inner lining layer to be pressed into the surface of the waterproof membrane by 1-2 mm.

[0027] Furthermore, the top of the elastic inner liner is provided with an annular sealing groove on the side facing the pile head;

[0028] In the annular sealing groove, sealing material is continuously injected and scraped smooth along the pile circumference.

[0029] Furthermore, before constructing the concrete structure, the fastening device is wrapped with insulating material.

[0030] This invention, by employing the above technical solutions, offers the following advantages and positive effects compared to existing technologies: Firstly, the combination of a dynamic pre-tightening component and an elastic inner lining layer creates a dual elastic compensation mechanism of "elastic fixing at the connection point + elastic rubber compression," breaking through the "rigid locking" mindset of existing technologies. Even as the waterproof membrane thins over time, the device can still self-adjust its shrinkage, achieving "constant force clamping" throughout its entire lifespan, completely solving the problem of stress relaxation and leakage. Secondly, by pressing the elastic inner lining layer tightly to the waterproof membrane under pre-tightening force, the serrated protrusions embed like barbs into the surface of the waterproof layer, forming "mechanical micro-interlocking," significantly improving pull-out and slip resistance. Thirdly, the elastic inner lining layer of this invention perfectly adapts to problems such as uneven surfaces and ellipticity deviations in cast-in-place piles in actual engineering projects, improving the construction tolerance rate of complex nodes. Furthermore, this invention physically isolates the waterproof finishing node from the subsequent concrete pouring environment, improving the first-time acceptance rate of construction quality. Attached Figure Description

[0031] Figure 1 This is a longitudinal sectional view of a fastening device for the termination of waterproof membrane at the pile head, as described in one embodiment of the present invention, installed on the pile head.

[0032] Figure 2 This is a cross-sectional view of a fastening device for the termination of waterproof membrane at the pile head, as described in one embodiment of the present invention, installed on the pile head.

[0033] Figure 3 for Figure 1 Enlarged view of region G in the image;

[0034] Figure 4 This is a schematic diagram of the structure of the elastic inner liner layer in one embodiment of the present invention;

[0035] Figure 5 This is a schematic diagram of the structure of a dynamic pre-tightening component in one embodiment of the present invention.

[0036] The numbers in the diagram are as follows:

[0037] 1-Pile head; 2-Concrete structure; 3-Subbase; 4-Waterproof coating; 5-Waterproof membrane;

[0038] 10-Annular outer shell; 11-Arc-shaped plate; 12-Connecting part;

[0039] 20 - Elastic inner liner; 21 - Serrated protrusion; 22 - Upper toothed surface; 23 - Outer toothed surface; 24 - Lower toothed surface; 25 - Annular sealing groove;

[0040] 30 - Dynamic preload assembly; 31 - Bolt; 32 - Nut; 33 - Preload component. Detailed Implementation

[0041] The fastening device and fastening method for the termination of waterproof membrane at pile heads provided by the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The advantages and features of the present invention will become clearer from the following description. 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.

[0042] Example 1

[0043] Combination Figures 1 to 5 As shown, this embodiment provides a fastening device for the termination of waterproof membrane at pile heads. This fastening device is applied at the connection between the pile head 1 and the cast-in-place concrete structure 2, with the outer wall of the pile head 1 covered by a waterproof membrane 5. The fastening device includes an annular outer shell 10, an elastic inner lining layer 20, and a dynamic pre-tightening component 30.

[0044] The annular outer shell 10 is formed by splicing together at least two arc-shaped plates 11, with connecting portions 12 at the ends of the arc-shaped plates 11. The arc-shaped plates 11 are spliced ​​together via the connecting portions 12 to form a complete annular structure that can be fitted onto the pile head. The connecting portions 12 are provided with mounting holes for subsequent fixing connections. Figure 2 As shown, the connecting parts 12 of the four arc-shaped plates 11 are spliced ​​together to form a ring-shaped outer shell.

[0045] Combination Figures 1 to 4 As shown, the elastic inner liner 20 is fixed to the inner wall of the annular outer shell 10, and the inner surface of the elastic inner liner 20 is provided with multiple serrated protrusions 21. These serrated protrusions 21 are multiple teeth distributed in a ring. The cross-section of each tooth includes an upper tooth surface 22, an outer tooth surface 23, and a lower tooth surface 24. The included angle between the upper tooth surface and the outer tooth surface is an acute angle, and the included angle between the lower tooth surface and the outer tooth surface is an obtuse angle. The included angle between the outer tooth surface and the vertical plane is 30° to 45°, and the included angle between the lower tooth surface and the vertical plane is 80° to 90°. This special tooth shape design allows the serrated protrusions 21 to more effectively engage the waterproof membrane, preventing the waterproof membrane from slipping off. The serrated protrusions 21 are pressed into the surface of the membrane by about 1-2 mm. The top of the elastic inner liner 20 has an annular sealing groove on the side facing the pile head. This sealing groove can accommodate sealing material to further enhance the waterproof effect. The sealing material can be polysulfide or polyurethane sealant.

[0046] When the annular outer shell 10 is fitted onto the pile head, the serrated protrusions 21 of the elastic inner liner 20 come into contact with the waterproof membrane. Because the elastic inner liner 20 is elastic, it can adapt to the unevenness of the pile head surface, ensuring that the serrated protrusions 21 uniformly press the waterproof membrane.

[0047] Combination Figures 1 to 5 As shown, the dynamic pre-tightening assembly 30 is used to fix the connecting portion 12 of adjacent curved plates 11 and apply a pre-tightening force to the connecting portion 12, causing the serrated protrusions 21 of the elastic inner liner 20 to press the waterproof membrane. The dynamic pre-tightening assembly 30 includes a fixing member and a pre-tightening member. The fixing member is used to splice and fix the connecting portion 12 of adjacent curved plates 11, and the pre-tightening member is used to apply a pre-tightening force to the connecting portion 12 of adjacent curved plates 11 to bring them closer together.

[0048] Specifically, the fasteners include a bolt 31 and a nut 32. One end of the bolt passes through a mounting hole in the connecting portion 12 of the adjacent arc-shaped plate 11 and is secured by the nut. A preload element is disposed between the head of the bolt and the connecting portion 12 or / and between the connecting portion 12 and the nut. The preload element 33 can be an elastic element such as a spring washer or a spring gasket, capable of generating a preload force when the bolt and nut are tightened. The fasteners can also be a pin and baffles fixed to both ends of the pin, with the preload element located between the baffles and the connecting portion 12 to provide the preload force.

[0049] During use, the annular outer shell 10 is fitted onto the pile head, so that the serrated protrusions 21 of the elastic inner lining layer 20 come into contact with the waterproof membrane. Then, the connecting parts 12 of the adjacent arc-shaped plates 11 are fixed by the dynamic pre-tightening assembly 30, and a pre-tightening force is applied. There is a gap between the splicing surfaces of the connecting parts 12. When the waterproof membrane deforms and its thickness changes, the pre-tightening force of the dynamic pre-tightening assembly 30 can adjust the gap, thereby compensating for the radial gap changes caused by the waterproof membrane in real time.

[0050] The fastening device works by using the pre-tightening force generated by the dynamic pre-tightening component 30 to press the serrated protrusions 21 of the elastic inner lining layer 20 against the waterproof membrane, preventing the waterproof membrane from falling off or shifting. Simultaneously, because there are gaps between the splicing surfaces of the connecting parts 12, and because the dynamic pre-tightening component 30 has an elastic adjustment function, when the thickness of the waterproof membrane changes due to temperature variations, stress deformation, or creep over time, the dynamic pre-tightening component 30 can automatically adjust the pre-tightening force to maintain a stable pressing effect on the waterproof membrane, avoiding leakage problems caused by deformation of the waterproof membrane.

[0051] The annular sealing groove 25 at the top of the elastic inner liner 20 can be filled with sealant or other sealing materials to form a second waterproof barrier, further improving the waterproof effect. The special toothed design of the serrated protrusions 21 allows the serrations to better engage the waterproof membrane, preventing it from slipping off under external force.

[0052] This fastening device has a simple structure and is easy to install. It can effectively solve the waterproofing problem at the end of the waterproof membrane at the pile head, improve the waterproofing performance at the connection between the pile head and the cast-in-place concrete structure, and extend the service life of the building.

[0053] Example 2

[0054] This embodiment provides a method for fastening the termination of waterproof membrane at pile heads, using the fastening device described in Embodiment 1. The method includes the following steps:

[0055] Step 1: Lay the waterproof membrane 5, and flip the waterproof membrane 5 along the pile head to the predetermined height.

[0056] In this step, the waterproof membrane 5 is first laid on the outer wall of the pile head, and then the waterproof membrane 5 is folded upwards along the pile head 1 until the predetermined height required by the design is reached. This ensures that the waterproof membrane 5 can completely cover the area that needs to be waterproofed. Of course, before laying the waterproof membrane, the bedding layer 3 can be cleaned first, and then a penetrating crystalline waterproof coating 4 can be applied to the bedding layer and the pile head to enhance the waterproofing effect.

[0057] Step 2: Wrap the annular outer shell 10 of the fastening device around the end of the waterproof membrane. Use the dynamic pre-tightening component 30 to pre-tighten the annular outer shell 10. After fixing, there is a gap between the splicing surfaces of the connection part 12. The serrated protrusions 21 of the elastic inner lining layer 20 press the waterproof membrane tightly.

[0058] In this step, the fastening device described in Embodiment 1 is used to wrap the annular outer shell 10 around the end of the waterproof membrane. A pre-tightening force is applied to the annular outer shell 10 by the dynamic pre-tightening component 30, allowing the serrated protrusions 21 of the elastic inner liner 20 to effectively press against the waterproof membrane. When the pre-tightening force is properly controlled, the serrated protrusions 21 of the elastic inner liner 20 can be pressed into the surface of the waterproof membrane by 1-2 mm. This depth of insertion ensures that the waterproof membrane is firmly fixed without causing excessive damage. After fixing, a certain gap is maintained between the splicing surfaces of the adjacent curved plate 11 connection portions 12, reserving space for possible subsequent adjustments.

[0059] Step 3: Construct the concrete structure, cover and fasten the fasteners and pile heads.

[0060] Before constructing the concrete structure, the fastening devices can be wrapped with insulating material to prevent direct contact between the concrete and the fastening devices, facilitating later maintenance or replacement. Then, the concrete structure is constructed, covering the fastening devices and pile heads to form a unified structure. Between sections of the concrete structure, the fastening devices are first wrapped with insulating materials such as foamed polyethylene strips to prevent them from being completely sealed to the concrete.

[0061] Step 4: When the waterproof membrane deforms and its thickness changes, the pre-tightening force of the dynamic pre-tightening component 30 can adjust the gap of the splicing surface of the connection part 12 and compensate for the radial gap change of the waterproof membrane in real time.

[0062] When changes in ambient temperature, external loads, or creep over time cause changes in the thickness of the waterproof membrane, the dynamic pre-tightening component 30 can automatically adjust the gap between the splicing surfaces of the connection part 12 through the automatic adjustment of the pre-tightening force. This provides real-time compensation for changes in the radial gap of the waterproof membrane, maintains a continuous compression effect on the waterproof membrane, and ensures that the waterproof effect is not affected.

[0063] In a preferred embodiment, the top of the elastic inner liner 20 has an annular sealing groove on the side facing the pile head. Sealing material is continuously injected and smoothed along the pile circumference within the annular sealing groove. This design provides a second waterproof barrier, further enhancing the waterproofing effect and effectively preventing moisture from seeping in through the gap between the waterproof membrane and the pile head.

[0064] The above method effectively solves the waterproofing problem at the termination of the waterproof membrane at the pile head, improving the waterproofing performance at the connection between the pile head and the cast-in-place concrete structure. This method is simple to operate, reliable in effect, and suitable for waterproofing treatment in various pile foundation projects.

[0065] 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.

[0066] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the appended claims.

Claims

1. A fastening device for the termination of waterproof membrane at a pile head, wherein the pile head is connected to a cast-in-place concrete structure, and the outer wall of the pile head is covered with waterproof membrane; the fastening device includes an annular outer shell, the annular outer shell being formed by splicing together at least two arc-shaped plates, the ends of the arc-shaped plates being provided with connecting portions; characterized in that... Also includes: An elastic inner lining layer is fixed to the inner wall of the annular outer shell, and the inner surface of the elastic inner lining layer is provided with a plurality of serrated protrusions; the annular outer shell is fitted onto the pile head, and the serrated protrusions are in contact with the waterproof membrane. The dynamic pre-tightening assembly is used to fix the connection of adjacent arc-shaped plates and apply a pre-tightening force to the connection. The serrated protrusions of the elastic inner lining layer press the waterproof membrane. There is a gap between the splicing surfaces of the connection. When the thickness of the waterproof membrane changes due to deformation, the pre-tightening force of the dynamic pre-tightening assembly can adjust the gap and compensate for the radial gap changes of the waterproof membrane in real time.

2. A fastening device for the termination of waterproof membrane at pile heads as described in claim 1, characterized in that, The dynamic pre-tightening assembly includes a fixing member and a pre-tightening member. The fixing member is used to splice and fix the connecting parts of adjacent arc-shaped plates, and the pre-tightening member is used to apply a pre-tightening force to the connecting parts of adjacent arc-shaped plates to bring them closer together.

3. A fastening device for the termination of waterproof membrane at pile heads as described in claim 2, characterized in that, The fasteners include bolts and nuts; The connecting part is provided with a mounting hole, and one end of the bolt passes through the mounting hole of the connecting part of the adjacent arc-shaped plate and is fixed by a nut; The preload is disposed between the head of the bolt and the connecting part or / and between the connecting part and the nut.

4. A fastening device for the termination of waterproof membrane at pile heads as described in claim 1, characterized in that, The serrated protrusions are multiple toothed strips distributed in a ring; The cross-section of the rack includes an upper tooth surface, an outer tooth surface, and a lower tooth surface. The angle between the upper tooth surface and the outer tooth surface is an acute angle, and the angle between the lower tooth surface and the outer tooth surface is an obtuse angle.

5. A fastening device for the termination of waterproof membrane at pile heads as described in claim 4, characterized in that, The angle between the external tooth surface and the vertical plane is 30° to 45°, and the angle between the lower tooth surface and the vertical plane is 80° to 90°.

6. A fastening device for the termination of waterproof membrane at pile heads as described in claim 1, characterized in that, The top of the elastic inner liner is provided with an annular sealing groove on the side facing the pile head.

7. A method for fastening the termination of waterproof membrane at pile heads, characterized in that, Includes the following steps: Lay the waterproof membrane, turning it upside down along the pile head to the predetermined height; The annular outer shell of the fastening device according to any one of claims 1 to 6 is wrapped around the end of the waterproof membrane, and the annular outer shell is fixed by pre-tightening force through the dynamic pre-tightening component. There is a gap between the splicing surfaces of the fixed connection part, and the serrated protrusions of the elastic inner lining layer press the waterproof membrane. Construct a concrete structure to cover the fastening devices and pile heads; When the thickness of the waterproof membrane changes due to deformation, the pre-tightening force of the dynamic pre-tightening component can adjust the gap between the splicing surfaces of the joint and compensate for the radial gap changes of the waterproof membrane in real time.

8. A method for fastening the termination of waterproof membrane at pile heads as described in claim 7, characterized in that, The pre-tightening force can press the serrated protrusions of the elastic inner lining into the surface of the waterproof membrane by 1-2 mm.

9. A fastening method for the termination of waterproof membrane at pile heads as described in claim 7, characterized in that, The top of the elastic inner liner is provided with an annular sealing groove on the side facing the pile head; In the annular sealing groove, sealing material is continuously injected and scraped smooth along the pile circumference.

10. A method for fastening the termination of waterproof membrane at pile heads as described in claim 7, characterized in that, Before constructing the concrete structure, wrap the fastening device with insulating material.

Images