Prestressed steel strand grouting plugging system

Abstract

The utility model discloses a prestressed steel strand grouting plugging system which comprises a prestressed steel strand, a top end grouting plugging device and a low-pressure grouting device, the top end grouting plugging device seals the top end of the prestressed steel strand and comprises an integrally-formed flexible sealing sleeve, and the low-pressure grouting device is arranged in the flexible sealing sleeve. The flexible sealing sleeve comprises a containing part on the upper side, a transition part between the upper side and the lower side, a sleeving part on the lower side and a sleeving part hose clamp, two functional pipes communicated with the containing part are arranged on the top face of the containing part, the functional pipes and the flexible sealing sleeve are integrally formed, and the low-pressure grouting device is connected with the low-pressure grouting pipe. The accommodating part and the transition part are filled with a sealing material which is vertically and downwards injected by a low-pressure grouting device through a low-pressure grouting pipe, and the part, penetrating into the accommodating part, of the prestressed steel strand is wrapped and sealed by the sealing material. The flexible sealing sleeve is designed to be matched with the waterproof capacity of polyurethane or epoxy resin, grouting plugging of the steel strand is completed, and the problem of underground leakage related to people's livelihood in the current building industry is greatly relieved.

Description

Technical Field

[0001] This utility model belongs to the field of prestressed pull-out pile construction, and in particular, it is a prestressed steel strand grouting and sealing system. Background Technology

[0002] The existing prestressed foundation piles are each equipped with six 21.8mm prestressed steel strands. After the prestressed piles are anchored into the foundation slab, and the prestressed steel strands are tensioned on the top surface of the slab, a working length of 100mm needs to be reserved. (See also...) Figure 1 As shown, the prestressed steel strands are slow-bonding steel strands. Each 21.8mm prestressed steel strand includes a central steel wire and two rings of peripheral steel wires surrounding the central steel strand, for a total of 19 steel wires. Each steel wire is coated with a slow-bonding adhesive, and finally, a PE pipe is used to form an outer shell. There are gaps between each steel wire within the steel strand bundle, and the outside is wrapped with PE pipe. Groundwater can easily seep upwards through the gaps between the steel wires and between the steel wires and the outer PE pipe, ultimately causing water seepage at the ends of the prestressed steel strands at the top of the prestressed tension pile.

[0003] Currently, the common approach to address water seepage in prestressed steel strands is to apply an external plastic coating for corrosion protection and then fill the gaps with structural material.

[0004] For example, publication number CN205975170U discloses a prestressed plastic-coated steel strand. This strand consists of a rubber layer extruded around a central steel wire, with outer steel wires tightly twisted around the rubber layer. The rubber layer is compressed to form a textured structure, extending into the gaps formed by the two tangential outer steel wires and the rubber layer. During the strand twisting process, the rubber layer deforms under the combined action of the outer and central steel wires, effectively filling the gaps between the outer and central steel wires and improving the internal density of the strand. This prevents water seepage from the gaps between the wires. However, after prestressing is applied, under the combined force of the central and peripheral steel wires, this structural filling often deforms simultaneously, potentially causing the rubber layer to be compressed into an ideal seal. This easily leads to new gaps, and the gaps between the peripheral steel wires and the outer plastic coating still exist, making it impossible to completely seal the ends of the prestressed steel strand.

[0005] Publication number CN211775123U discloses a sealing structure for a slow-setting bonded prestressed steel strand. This structure involves applying a sealing cap to the end of the steel strand, the cap containing a curing agent. The curing agent flows into the end of the steel strand to accelerate the curing of the slow-setting adhesive. A snap-fit ​​structure is required between the sealing cap and the end of the steel strand to ensure a tight seal. This sealing cap provides external sealing to the steel strand, requiring a redesign of the strand structure to accommodate the cap. Furthermore, there is a risk of curing agent spillage, and it is impossible to monitor whether the curing agent completely fills the gaps between the wires at the end of the steel strand. Utility Model Content

[0006] The purpose of this invention is to provide a grouting and sealing system for prestressed steel strands. This system aims to address the technical problem in existing prestressed steel strand length sealing measures where structural filling cannot be completely sealed under stress. It also aims to solve the problems of redesigning the steel strand structure and the cumbersome connection between the prefabricated sealing cap and the structure when using an external sealing cap. Furthermore, it addresses the technical problems of unmonitored curing agent overflow from the sealing cap and the degree of curing agent flow into the steel strand.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] A prestressed steel strand grouting and sealing system includes a prestressed steel strand, a top grouting and sealing device, and a low-pressure grouting device. The top grouting and sealing device seals the top end of the prestressed steel strand.

[0009] The top grouting plug includes an integrally formed flexible sealing sleeve, which includes an upper receiving portion, a transition portion between the upper and lower portions, a lower sleeve portion, and a sleeve portion hose clamp.

[0010] The size of the receiving part is larger than the size of the socket part, and the size of the transition part is larger at the top and smaller at the bottom. The upper side connects to the receiving part, and the lower side connects to the socket part.

[0011] The top surface of the receiving part is provided with two functional pipes that communicate with the receiving part. The functional pipes are integrally formed with the flexible sealing sleeve. They are a low-pressure grouting pipe and an exhaust overflow observation pipe, respectively. The bottom of the low-pressure grouting device is connected to the top of the low-pressure grouting pipe. The low-pressure grouting device is set vertically. The receiving part and the transition part are filled with sealing material injected vertically downward by the low-pressure grouting device through the low-pressure grouting pipe. The part of the prestressed steel strand that penetrates into the receiving part is wrapped and sealed by the sealing material. The exhaust overflow observation pipe is also filled with sealing material and overflows.

[0012] The prestressed steel strand is in a state of bearing tension after being tensioned. The part of the prestressed steel strand that extends out of the prestressed anchor at the top of the pull-out prestressed foundation pile is the working section. The top grouting sealer seals the top part of the working section. The length of the working section that penetrates into the top grouting sealer is not less than 50mm.

[0013] The top of the working section extends from the socket part through the transition part to the insertion receiving part. The socket part's throat clamp ring sleeve seals the socket part and the working section on the outer periphery of the socket part.

[0014] The flexible sealing sleeve and functional tube are integrally molded from natural rubber.

[0015] Rubber sealing plugs are inserted into the low-pressure grouting pipe and the vent overflow observation pipe.

[0016] The low-pressure grouting pipe is located in the center of the top surface of the receiving part, and the exhaust overflow observation pipe is located at the edge of the top surface of the receiving part. The height of the low-pressure grouting pipe is greater than the height of the exhaust overflow observation pipe.

[0017] The size of the receiving part is larger than that of the socket part. The receiving part is a large-diameter cylinder, and the transition part is an inverted frustum-shaped cone. The socket part is a small-diameter cylinder. The inner diameter of the socket part is larger than the outer diameter of the prestressed steel strand. The wall thickness of the receiving part is smaller than that of the socket part, and the wall thickness of the receiving part is also smaller than that of the functional tube.

[0018] The sealing material is modified polyurethane or modified epoxy resin.

[0019] The hose clamp of the socket is made of stainless steel.

[0020] Compared with the prior art, this utility model has the following features and beneficial effects:

[0021] This utility model designs a flexible sealing sleeve to fit over the top of the prestressed steel bar, and uses a low-pressure grouting device to inject grout into the sleeve. Combined with the waterproofing capabilities of sealing materials such as modified polyurethane or modified epoxy resin, the grouting seal of the steel strand ends is completed, preventing subsequent water leakage and greatly alleviating the problem of underground leakage that is currently a major concern in the construction industry.

[0022] Compared with the structural improvements of prestressed steel strands in the prior art, this utility model adopts external sealing, and the sealing material forms a solid body inside the flexible sealing sleeve, which ensures that the prestressed steel strands can be completely sealed even under stress, and ensures that there will be no water leakage.

[0023] This application describes the external injection of sealing material into a flexible sealing sleeve. It employs two functional tubes: one for grouting, which, compared to existing technologies that pre-fill with curing agent, ensures complete sealing of the top of the prestressed steel strands; and the other serves as an venting and overflow observation tube, ensuring the monitorability of the compactness within the flexible sealing sleeve after grouting. The bottom of the flexible sealing sleeve is locked in place by a hose clamp at the joint, preventing sealant overflow. After construction, a rubber sealing plug is used to seal the functional tubes, allowing for further construction steps and subsequent direct burial.

[0024] This utility model's process can be completed by only one operator, which not only solves the problem of leakage in prestressed steel strands but also significantly improves on-site construction efficiency. It is safe, applicable, and has great promotional and practical value. Its application will generate good economic and social benefits.

[0025] This utility model is applicable to the pre-sealing of water seepage at the end of the pre-reserved steel strand at the top of prestressed tension piles or the sealing treatment of water seepage at the end of the prestressed steel strand tensioning. Attached Figure Description

[0026] The present invention will now be described in further detail with reference to the accompanying drawings.

[0027] Figure 1 This is a schematic diagram of the cross-section of prestressed steel strand in the prior art.

[0028] Figure 2 This is a schematic diagram of the connection structure between the top grouting sealing device and the prestressed steel strand of this utility model.

[0029] Figure 3 yes Figure 2 A top-view structural diagram.

[0030] Figure 4 This is a schematic diagram of the overall structure of this utility model.

[0031] Figure reference numerals: 1-Low-pressure grouting device, 2-Flexible sealing sleeve, 21-Receiving part, 22-Transition part, 23-Socket part, 24-Socket part hose clamp, 3-Low-pressure grouting pipe, 4-Exhaust grout overflow observation pipe, 5-Sealing material, 6-Prestressed steel strand, 61-Working section, 7-Prestressed anchor, 8-Rubber sealing plug, 9-Central steel wire, 10-Peripheral steel wire, 11-PE pipe outer shell. Detailed Implementation

[0032] See Figure 1 This is a schematic diagram of the cross-section of a prestressed steel strand in the prior art, which includes one central steel wire 9 and 18 peripheral steel wires 10. There are gaps between the peripheral steel wires 10 and between the peripheral steel wires 10 and the central steel wire 9. The steel wires are covered with a PE pipe shell 11.

[0033] See the examples. Figure 2-4 As shown, a prestressed steel strand grouting and sealing system includes a prestressed steel strand 6, a top grouting and sealing device, and a low-pressure grouting device 1.

[0034] Prestressed steel strand 6 extends beyond the prestressed tension pile. The prestressed foundation pile is 23.5 meters long and 0.7 meters in diameter, with six steel strands of diameter D=21.8mm per pile. The prestressed steel strand 6 is in a tensioned state. After the prestressed tension pile is anchored into the foundation slab, the prestressed steel strand is tensioned at the top surface of the foundation slab, leaving a working length of 100mm. That is, the part of the prestressed steel strand 6 extending beyond the prestressed anchor 7 at the top of the tension prestressed foundation pile is the working section 61, with a length H of 100mm. The top of the working section 61 is sealed by a top grouting sealer. The length h of the working section 61 of the prestressed steel strand 6 penetrating the top grouting sealer is not less than 50mm.

[0035] The top grouting plug includes an integrally formed flexible sealing sleeve 2, which includes an upper receiving portion 21, a transition portion 22 between the upper and lower sides, a lower sleeve portion 23, and a sleeve portion hose clamp 24.

[0036] The size of the receiving part 21 is larger than the size of the socket part 23. The size of the transition part 22 is larger at the top and smaller at the bottom. It connects to the receiving part 21 on the upper side and to the socket part 23 on the lower side. The size of the receiving part 21 is larger than the size of the socket part 23. The receiving part 21 is a large-diameter cylinder. The transition part 22 is an inverted frustum-shaped cone. The socket part 23 is a small-diameter cylinder. The inner diameter of the socket part 23 is larger than the outer diameter of the working section 61. The wall thickness of the receiving part 21 is smaller than the wall thickness of the socket part 23.

[0037] In this embodiment, the height a of the receiving part 21 is 50 mm, the diameter b of the receiving part is 66 mm, the height c of the sleeve part 23 is 20 mm, the diameter d of the sleeve part 23 is 35 mm, the wall thickness of the receiving part 21 is 2 mm, and the wall thickness of the sleeve part 23 is 3 mm.

[0038] The top of the working section 61 extends from the socket 23 through the transition section 22 to the insertion receiving section 21. The socket hose clamp 24, annularly sleeved around the outer periphery of the socket 23, seals the socket 23 and the working section 61. In this embodiment, the socket hose clamp 24 is a stainless steel clamp.

[0039] The top surface of the receiving part 21 is provided with two functional tubes that communicate with the receiving part 21. The functional tubes are integrally formed with the flexible sealing sleeve. In this embodiment, the flexible sealing sleeve 2 and the functional tubes are integrally formed with natural rubber. There must be no defects such as cracks or sand holes to ensure the sealing performance of the plug.

[0040] The functional pipes are a low-pressure grouting pipe 3 and an exhaust overflow observation pipe 4. The bottom of the low-pressure grouting device 1 is connected to the top of the low-pressure grouting pipe 3. The low-pressure grouting device 1 is vertically arranged. The low-pressure grouting pipe 3 is located at the center of the top surface of the receiving part 21. The exhaust overflow observation pipe 4 is located at the edge of the top surface of the receiving part 21. The height of the low-pressure grouting pipe 3 is greater than the height of the exhaust overflow observation pipe 4. The wall thickness of the receiving part 21 is also less than the wall thickness of the functional pipes.

[0041] In this embodiment, the wall thickness of the functional tube is 3mm; the functional tube is a variable cross-section tube, with the diameter e of the enlarged top section being 14mm and the diameter f of the remaining part being 10mm.

[0042] The receiving section 21 and the transition section 22 are filled with sealing material 5 injected vertically downwards through the low-pressure grouting pipe 3 by the low-pressure grouting device 1. The portion of the working section that extends into the receiving section 21 is sealed by the sealing material 5, and the vent overflow observation pipe 4 is also filled with sealing material 5 and overflows. In this embodiment, the sealing material 5 is modified polyurethane or modified epoxy resin. Rubber sealing plugs 8 are also inserted into the low-pressure grouting pipe 3 and the vent overflow observation pipe 4.

[0043] The construction process of this utility model is as follows:

[0044] Step 1: Prefabricate the top grouting sealer according to the dimensions of the prestressed steel strand 6;

[0045] Step 2: First, insert the prestressed steel strand 6 through the bottom sleeve part 23, with the steel strand inserted 50mm. Then, tighten and lock the sleeve part hose clamp 24 of the sleeve part 23.

[0046] Step 3: Use the low-pressure grouting device 1 to connect to the top grouting port of the low-pressure grouting pipe 3 to grout the sealing material 5. Wait until the venting and overflow observation pipe 4 starts to vent and finally obvious overflow occurs, then stop grouting.

[0047] Step 4: Use the matching rubber sealing plug 8 to tightly seal the openings of the vent overflow observation pipe 4 and the low-pressure grouting pipe 3.

[0048] Step 5: After the sealing material 5 inside the flexible sealing sleeve 2 has solidified, the top grouting and sealing work of the prestressed steel strand is completed.

[0049] Step 6: The flexible sealing sleeve 2 and the functional tube do not need to be removed and can be directly buried in the foundation slab during the subsequent foundation slab construction.

Claims

1. A prestressed steel strand grouting plugging system, characterized in that: The prestressed steel strand (6), the top grouting stopper and the low-pressure grouting device (1), the outer side of the steel wire of the prestressed steel strand (6) is coated with a PE pipe shell (11), the top grouting stopper seals the top end part of the prestressed steel strand (6), The top grouting stopper comprises a flexible sealing sleeve (2) integrally formed, the flexible sealing sleeve (2) comprises an accommodating part (21) on the upper side, a transition part (22) between the upper and lower sides, a sleeving part (23) on the lower side and a sleeving part throat ring (24), The size of the accommodating part (21) is larger than that of the sleeving part (23), the size of the transition part (22) is large on the upper side and small on the lower side, the upper side is connected with the accommodating part (21), and the lower side is connected with the sleeving part (23), Two functional pipes in communication with the accommodating part (21) are arranged on the top surface of the accommodating part (21), the functional pipes are integrally formed with the flexible sealing sleeve and are respectively a low-pressure grouting pipe (3) and an exhaust overflow grouting observation pipe (4), the bottom of the low-pressure grouting device (1) is connected with the top of the low-pressure grouting pipe (3), the low-pressure grouting device (1) is vertically arranged, the accommodating part (21) and the transition part (22) are filled with sealing material (5) injected vertically downward through the low-pressure grouting pipe (3) by the low-pressure grouting device (1), the part of the prestressed steel strand (6) deep into the accommodating part (21) is wrapped and sealed by the sealing material (5), and the exhaust overflow grouting observation pipe (4) is also filled with the sealing material (5) and overflows grouting.

2. The prestressed steel strand grouting plugging system according to claim 1, characterized in that: The prestressed steel strand (6) is in a force-holding state after the tension is applied, the part of the prestressed steel strand (6) protruding from the prestressed anchor device (7) at the top of the uplift prestressed foundation pile is a working section (61), the top grouting stopper seals the top end part of the working section (61), and the length of the working section (61) penetrating into the top grouting stopper is not less than 50 mm.

3. The prestressed steel strand grouting plugging system according to claim 2, characterized in that: The top of the working section (61) is from the sleeving part (23) through the transition part (22) to the accommodating part (21), and the sleeving part throat ring (24) is annularly sleeved on the outer periphery of the sleeving part (23) to seal between the sleeving part (23) and the working section (61).

4. The prestressed steel strand grouting plugging system according to claim 1, characterized in that: The flexible sealing sleeve (2) and the functional pipes are integrally formed by natural rubber.

5. The prestressed steel strand grouting plugging system according to claim 1 or 4, characterized in that: Rubber sealing plugs (8) are arranged on the low-pressure grouting pipe (3) and the exhaust overflow grouting observation pipe (4).

6. The prestressed steel strand grouting plugging system according to claim 1, characterized in that: The low-pressure grouting pipe (3) is located at the central top surface of the accommodating part (21), the exhaust overflow grouting observation pipe (4) is located at the edge of the top surface of the accommodating part (21), and the height of the low-pressure grouting pipe (3) is greater than that of the exhaust overflow grouting observation pipe (4).

7. The prestressed steel strand grouting plugging system according to claim 1 or 6, characterized in that: The size of the accommodating part (21) is larger than that of the sleeving part (23), the accommodating part (21) is a large-diameter cylindrical shape, the transition part (22) is a reverse tapered table type, the sleeving part (23) is a small-diameter cylindrical shape, the inner diameter of the sleeving part (23) is greater than the outer diameter of the prestressed steel strand (6), the wall thickness of the accommodating part (21) is smaller than that of the sleeving part (23), and the wall thickness of the accommodating part (21) is also smaller than that of the functional pipes.

8. The prestressed steel strand grouting plugging system according to claim 1, characterized in that: The sealing material (5) is modified polyurethane or modified epoxy resin.

9. The prestressed steel strand grouting plugging system according to claim 1, characterized in that: The sleeving part throat ring (24) is a stainless steel ring.

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