Post-cast strip impervious structure of large U-shaped prestressed thin-wall aqueduct body

Abstract

The invention relates to the field of building construction, in particular to a post-cast strip impervious structure of a large U-shaped prestressed thin-wall aqueduct body. Comprising a post-cast strip anti-seepage structure, the post-cast strip anti-seepage structure is arranged between two adjacent main prestress main groove bodies, the post-cast strip anti-seepage structure comprises two post-cast strips, the two post-cast strips are symmetrically arranged, and the side walls, away from each other, of the two post-cast strips are in butt joint with the corresponding main prestress main groove bodies; an expansion joint is arranged between the two post-cast strips, a metal waterstop is arranged at the butt joint position of the post-cast strips and the main prestress main groove body, an elastic waterstop is installed on the top face of the expansion joint, and construction joints, in butt joint with the main prestress main groove body, of the post-cast strips are processed into chiseling faces. The water stop design of the expansion joint between the U-shaped aqueduct bodies is replaceable, and maintenance is convenient.

Description

Technical Field

[0001] The invention relates to the field of building construction, and in particular to an anti-seepage structure of a post-cast belt of a large-scale U-shaped prestressed thin-wall aqueduct body. Background Art

[0002] Aqueduct refers to an overhead water channel that transports water across rivers, valleys, depressions and roads. Among them, large-scale large-span aqueducts use prestressed simply supported thin-walled U-shaped trough structures.

[0003] At present, in-situ cast-in-place construction is adopted for large-span heavy-duty prestressed simply supported thin-walled U-shaped troughs. Post-tensioning method is generally used for steel bundle tensioning. In order to meet the space requirements for prestressing tensioning operations, post-cast strips are reserved at the ends of the two adjacent aqueduct troughs.

[0004] The prestressed simply supported thin-walled U-shaped trough is cast in two parts: the main prestressed main trough and the post-cast strip. The post-cast strip adopts W6-F100C50 slightly expanding reinforced concrete structure + construction joint copper waterstop + roughening of the joint surface of new and old concrete to prevent leakage of the trough.

[0005] In order to adapt to the needs of deformation of the beam-type U-shaped trough structure, an expansion joint is set in the middle of the post-cast strip at the ends of the two adjacent aqueduct troughs.

[0006] The large U-shaped beam-type trough expansion joint has a width of 5cm. In order to meet the water conveyance function of the trough after completion, the expansion joint adopts a water-stop structure.

[0007] The U-shaped trough body post-casting belt structure is waterproof, including the structure body and construction joint anti-seepage. The U-shaped trough body uses W6-F100C50 micro-expansion concrete. During the construction process, the concrete structure is prone to cracks due to poor vibration or inadequate maintenance, which leads to leakage in the later stage of the trough body. The main causes of construction joint leakage include two aspects: the contact between the new and old concrete is not tight and the copper water stop installation quality is unqualified.

[0008] The U-shaped trough expansion joint water-stopping structure should have the characteristics of adapting to the deformation of the expansion joint, and at the same time be required to have the function of preventing leakage and being easy to maintain. Summary of the invention

[0009] The purpose of the present invention is to provide a large-scale U-shaped prestressed thin-walled aqueduct body post-casting belt anti-seepage structure to solve the above-mentioned problems. The present invention ensures that the U-shaped trough structure has an anti-seepage function, and its construction joints are leak-proof; the expansion joints between two adjacent beam-type U-shaped trough bodies have an expansion function, and at the same time, under the working conditions of expansion or displacement between the two adjacent trough bodies, its anti-seepage function meets the needs of safe water delivery. In addition, due to the long-term use of expansion joint water-stopping materials (such as rubber water-stopping plates), aging will occur. Therefore, the expansion joint water-stopping design between the U-shaped aqueduct body is a replaceable and easy-to-maintain water-stopping structure.

[0010] To achieve the above object, the present invention provides the following solutions:

[0011] A large-scale U-shaped prestressed thin-walled aqueduct body post-casting strip anti-seepage structure, including a post-casting strip anti-seepage structure, which is arranged between two adjacent main prestressed main trough bodies, and the post-casting strip anti-seepage structure includes two post-casting strips, which are symmetrically arranged, and the side walls of the two post-casting strips that are away from each other are connected to the corresponding main prestressed main trough bodies, and an expansion joint is provided between the two post-casting strips, and a metal waterstop is provided at the connection between the post-casting strip and the main prestressed main trough body, and an elastic waterstop is installed on the top surface of the expansion joint, and the construction joint between the post-casting strip and the main prestressed main trough body is treated as a roughened surface.

[0012] Preferably, the surface treatment of the construction joint of the main prestressed main trough body is to roughen the surface, remove scum and wash it, and apply at least two coats of concrete interface treatment agent after the surface is dry.

[0013] Preferably, the expansion joint is filled with polyethylene caulking plates.

[0014] Preferably, a plurality of L-shaped screws are cast in the post-cast strip, the top ends of the L-shaped screws extend out of the top surface of the post-cast strip, and the elastic waterstop is installed on the top surface of the post-cast strip via the L-shaped screws and nuts.

[0015] Preferably, the elastic waterstop strip and the post-cast strip are bonded together by GB composite rubber sheet and adhesive.

[0016] Preferably, the surface of the water-conducting side of the expansion joint of the post-cast strip is set as a "concave" shaped trough body, the elastic waterstop is installed in the "concave" shaped trough body, the middle of the top surface of the elastic waterstop is abutted against the polyethylene caulking plate, the space between the polyethylene caulking plate and the "concave" shaped trough body is filled with acrylic mortar, and the top surface of the polyethylene caulking plate located in the "concave" shaped trough body is sealed by polysulfide sealant.

[0017] The present invention has the following technical effects:

[0018] A whole piece of buried copper waterstop is set between the prestressed thin-walled trough body and the post-casting strip of the U-shaped aqueduct, the roughness level of the construction joint is set, the concrete interface treatment agent is applied and the curing agent is sprayed to strengthen the concrete maintenance and other technical measures to enhance the bonding strength between the new and old concrete, reduce the probability of harmful cracks along the construction joint of the U-shaped trough body, and improve the overall anti-seepage performance.

[0019] The present invention designs a method for manufacturing a water-stop structure for an expansion joint between two adjacent beam-type U-shaped trough bodies. The Ω-shaped GB composite rubber water-stop strip arranged in the expansion joint and the staggered surface of the post-casting strip concrete are bonded with adhesive and fixed and pressed with a stainless steel pressure plate, thereby preventing leakage caused by dislocation and deformation of the U-shaped trough body joint caused by hydraulic shock, temperature change, earthquake, etc.

[0020] The stainless steel pressure plate of the Ω-shaped rubber waterstop is set in a "⌒" shape, and the edges on both sides are polished into semicircular shapes. It is fastened by pre-buried screws at intervals of 100mm to improve the quality of water-stop sealing.

[0021] A "concave" groove is set on the water-facing surface of the expansion joint between two adjacent beam-type U-shaped trough bodies. The inner expansion joint is filled with polysulfide sealing paste, and the post-casting zone of the trough body is filled with acrylic mortar, which not only ensures the deformation requirements between the U-shaped trough bodies, but also meets the functional requirements of water stopping, anti-scouring and wear resistance.

[0022] A "concave" groove is set on the water-facing surface of the expansion joint between two adjacent beam-type U-shaped trough bodies, and the rubber waterstop is buried in the bottom of the groove by bonding and pressing plates to prevent scouring and delay the aging of the waterstop, and is also easy to dismantle and replace for maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0024] Figure 1 It is a schematic diagram of the structure of a large-scale U-shaped aqueduct with a central beam according to the present invention.

[0025] Figure 2 It is a side view of the prestressed thin-walled trough body and post-cast strip structure of the large-scale U-shaped aqueduct with a central beam according to the present invention.

[0026] Figure 3 It is a top view of the prestressed thin-walled trough body and post-cast strip structure of the large-scale U-shaped aqueduct with a central beam according to the present invention.

[0027] Figure 4 for Figure 2 AA cross-sectional schematic diagram, schematic diagram of the anti-seepage structure of the post-casting belt structure of the beam-type U-shaped trough in the present invention.

[0028] Figure 5 for Figure 1 and Figure 2 Schematic diagram of the BB cross section.

[0029] Figure 6 for Figure 1 and Figure 2Schematic diagram of CC cross section.

[0030] Figure 7 for Figure 1 and Figure 2 The enlarged schematic diagram of the middle D portion is also a schematic diagram of the expansion joint water-stopping structure between two adjacent beam-type U-shaped troughs in the present invention.

[0031] Among them, 1. Anti-seepage structure of post-cast strip; 2. Main prestressed main trough; 3. Large U-shaped aqueduct with n-span beam; 4. Large U-shaped aqueduct with n+1-span beam; 5. Large U-shaped aqueduct with n+2-span beam; 6. Post-cast strip; 7. Construction joint; 8. Expansion joint; 9. Metal waterstop; 10. Roughened surface; 11. Concrete interface treatment agent; 12. Elastic waterstop; 13. Polysulfide sealing paste; 14. GB composite rubber sheet; 15. Retaining adhesive; 16. L-shaped screw; 17. Polyethylene caulking plate; 18. Acrylic mortar; 19. Stainless steel pressure plate; 20. Nut. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0034] Reference Figures 1 to 7 As shown, the present embodiment provides a large-scale U-shaped prestressed thin-walled aqueduct body post-cast strip anti-seepage structure, including a post-cast strip anti-seepage structure 1, the post-cast strip anti-seepage structure 1 is arranged between two adjacent main prestressed main trough bodies 2, the post-cast strip anti-seepage structure 1 includes two post-cast strips 6, the two post-cast strips 6 are symmetrically arranged, the side walls of the two post-cast strips 6 that are away from each other are connected to the corresponding main prestressed main trough bodies 2, an expansion joint 8 is provided between the two post-cast strips 6, a metal waterstop 9 is provided at the joint between the post-cast strip 6 and the main prestressed main trough body 2, an elastic waterstop 12 is installed on the top surface of the expansion joint 8, and the construction joint 7 where the post-cast strip 6 and the main prestressed main trough body 2 are connected is treated as a roughened surface 10.

[0035] According to a further optimization scheme, the surface treatment of the construction joint 7 of the main prestressed main trough body 2 is to roughen the surface 10, clean the scum and wash it, and apply at least two coats of concrete interface treatment agent 11 after the surface is dried.

[0036] According to a further optimized solution, the expansion joint 8 is filled with a polyethylene caulking plate 17 .

[0037] A further optimized solution is that a plurality of L-shaped screws 16 are cast in the post-cast strip 6, the top ends of the L-shaped screws 16 extend out of the top surface of the post-cast strip 6, and the elastic waterstop 12 is installed on the top surface of the post-cast strip 6 through the L-shaped screws 16 and the nuts 20.

[0038] According to a further optimized solution, the elastic water stop strip 12 and the post-cast strip 6 are bonded together by a GB composite rubber sheet 14 and a retaining adhesive 15 .

[0039] To further optimize the solution, the surface of the water conveying side of the expansion joint 8 of the post-cast strip 6 is set as a "concave" shaped trough, the elastic waterstop 12 is installed in the "concave" shaped trough, and the middle of the top surface of the elastic waterstop 12 is abutted with a polyethylene caulking plate 17, and the space between the polyethylene caulking plate 17 and the "concave" shaped trough is filled with acrylic mortar 18, and the top surface of the polyethylene caulking plate 17 located in the "concave" shaped trough is sealed by a polysulfide sealant 13.

[0040] The construction process of this embodiment is as follows:

[0041] The main prestressed main trough 2 of the nth span beam type large U-shaped aqueduct prestressed thin-walled trough 3, the n+1th span beam type large U-shaped aqueduct prestressed thin-walled trough 4, and the n+2th span beam type large U-shaped aqueduct prestressed thin-walled trough 5 are cast in situ. The main prestressed main trough 2 is U-shaped, the metal waterstop 9 is made of copper, and the elastic waterstop 12 is a shaped rubber waterstop.

[0042] Step 1: cast the main prestressed main trough body 2 of the large U-shaped aqueduct prestressed thin-walled trough hole by hole, and reserve a post-casting strip 6 between two adjacent main prestressed main trough bodies 2. When the main prestressed main trough body 2 is cast in place, a ┘└-shaped steel plate clamp is set through the end mold to install and fix the copper water stop strip 9.

[0043] Step 2: Concrete construction of post-cast zone 6.

[0044] 1. Roughen the joint surface between the new and old concrete. The joint surface between the main prestressed main trough 2 and the post-casting strip 6 is roughened to form a roughened surface 10, and the area of ​​fresh concrete exposed by the roughening is not less than 100%; after roughening, use a wire brush to clean the scum and wash it, and after the concrete surface is dry, apply at least two coats of concrete interface treatment agent 11;

[0045] 2. Tie the steel bars of the post-casting strip 6 of the two adjacent beam-type U-shaped troughs;

[0046] 3. Joint setting. A polyethylene caulking plate 17 with a thickness of 50 mm is installed between two adjacent beam-type U-shaped troughs to form an expansion joint 8. A #-shaped mesh card is set in the steel bars of the post-casting strip 6 of the two adjacent spans of the U-shaped trough to accurately position and vertically penetrate the polyethylene caulking plate 17, so that the caulking plate will not deviate during the concrete pouring process of the post-casting strip 6.

[0047] 4. The L-shaped screw 16 is embedded in the concrete. The Ф10 L-shaped screw 16 is fixed by welding the #-shaped Ф6 steel mesh and the post-casting belt 6 steel bars; the straight edge of the L-shaped screw 16 is lateral to the inside of the U-shaped groove;

[0048] 5. Install the inner and outer formwork and support system of the post-casting strip 6 of the adjacent two beam-type U-shaped troughs; the exposed part of the L-shaped screw 16 is fixed to the formwork through the nut 20 to ensure that the length of the exposed part of the concrete surface is accurately controlled to be above 35mm;

[0049] 6. Concrete pouring of post-casting strip 6. After adjusting the axis position and exposed length of the embedded L-shaped screw 16, pour the concrete of post-casting strip 6; when the concrete is poured to 1 / 4 to 1 / 3 of the height of the embedded screw, correct the embedded position again; after removing the mold, the exposed part of the embedded screw is protected by a PVC pipe. The post-casting strip 6 is covered with a concrete water-retaining curing film and the curing time should not be less than 14 days.

[0050] Step three: Install the expansion joint water-stop structure.

[0051] 1. After the concrete of the post-casting belt 6 of the U-shaped groove is poured and reaches the designed strength, use a wire brush to clean the concrete scum of the groove, and then clean the pre-buried polyethylene caulking plate 17 of the expansion joint in the groove. The cleaning depth should be consistent with the nose height of the elastic water stop belt 12;

[0052] 2. After cleaning the dust with high-pressure air, evenly apply adhesive 15 on the contact surface between the straight edge of the elastic waterstop 12 and the concrete, install the GB composite rubber plate 14 and the rubber waterstop 12, and the elastic waterstop 12 is Ω-shaped.

[0053] 3. Install the pressure plate. After the elastic water stop 12 is bonded and fixed, install the stainless steel pressure plate 19, which is "⌒" shaped, with the convex surface facing the inner side of the U-shaped groove; install the ordinary gasket first, then the spring gasket, and finally the nut 20; first tighten the nut 20 in a fixed manner, and finally apply a uniform tightening torque of 35N·m.

[0054] Step 4: Water-stop effect inspection. After the expansion joint water-stop structure is installed, plugs are set at both ends of the aqueduct body, and water is filled to inspect the joint water-stop, including the leakage of the U-shaped main prestressed main trough 2, post-casting strip 6, construction joint 7, and expansion joint 8; observe once every 10cm of water until the designed water level; let it stand for 48 hours, add water to the increased water level line and observe continuously for one week; if there is no leakage point in the entire bridge trough body, it is confirmed that the water-stop effect inspection is qualified.

[0055] Step 5, backfilling acrylic mortar 18 and polysulfide sealant 13.

[0056] 1. Acrylic emulsion mortar 18 is prepared and mixed according to the mix ratio determined by the test and the construction method is adopted by manual spreading and pressing.

[0057] 2. Before construction, use a wire brush to remove dust and dirt on the concrete surface, then rinse and moisten with clean water. First use acrylic emulsion slurry to prime, then apply acrylic emulsion mortar in layers, with each layer thickness controlled at about 5mm. About 4 hours after applying acrylic emulsion mortar 18, cover with concrete water-retaining curing film and maintain for 7 days.

[0058] 3. Install a 50mm polyethylene caulking plate 17 at the expansion joint 8 in the groove. When backfilling the acrylic mortar 18, ensure that the polyethylene caulking plate 17 is vertical and circumferentially in the same section.

[0059] 4. Remove the polyethylene caulking plate 17 in the groove on the surface of the water supply side of the U-shaped groove after the expansion joint 8 is cast, and the depth is controlled at 15mm; then fill the polysulfide sealant 13 in the groove, and grind it to make it smooth while filling.

[0060] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0061] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A large-scale U-shaped prestressed thin-walled aqueduct body post-casting zone anti-seepage structure, characterized in that: The invention comprises a post-cast strip anti-seepage structure (1), wherein the post-cast strip anti-seepage structure (1) is arranged between two adjacent main prestressed main trough bodies (2), wherein the post-cast strip anti-seepage structure (1) comprises two post-cast strips (6), wherein the two post-cast strips (6) are symmetrically arranged, and the side walls of the two post-cast strips (6) which are away from each other are butted against the corresponding main prestressed main trough bodies (2), and an expansion joint (8) is arranged between the two post-cast strips (6), and a metal water stop strip (9) is arranged at the butt joint between the post-cast strip (6) and the main prestressed main trough body (2), and an elastic water stop strip (12) is installed on the top surface of the expansion joint (8), and the construction joint (7) where the post-cast strip (6) and the main prestressed main trough body (2) are butt jointed is treated as a roughened surface (10).

2. A large-scale U-shaped prestressed thin-walled aqueduct body post-casting zone anti-seepage structure according to claim 1, characterized in that: The surface of the construction joint (7) of the main prestressed main trough (2) is treated by roughening the surface (10), then cleaning the scum and washing, and applying at least two coats of a concrete interface treatment agent (11) after the surface is dried.

3. The large-scale U-shaped prestressed thin-walled aqueduct body post-casting zone anti-seepage structure according to claim 1 is characterized in that: The expansion joint (8) is filled with a polyethylene caulking plate (17).

4. The large-scale U-shaped prestressed thin-walled aqueduct body post-casting zone anti-seepage structure according to claim 1 is characterized in that: A plurality of L-shaped screws (16) are cast in the post-cast strip (6), and the top ends of the L-shaped screws (16) extend out of the top surface of the post-cast strip (6). The elastic water stop strip (12) is installed on the top surface of the post-cast strip (6) through the L-shaped screws (16) and nuts (20).

5. The large-scale U-shaped prestressed thin-walled aqueduct body post-casting zone anti-seepage structure according to claim 1 is characterized in that: The elastic water stop strip (12) and the post-cast strip (6) are bonded together by a GB composite rubber sheet (14) and a retaining adhesive (15).

6. The large-scale U-shaped prestressed thin-walled aqueduct body post-casting zone anti-seepage structure according to claim 3 is characterized in that: The surface of the water conveying side of the expansion joint (8) of the post-casting strip (6) is set as a "concave" shaped trough body, the elastic water stop strip (12) is installed in the "concave" shaped trough body, the middle of the top surface of the elastic water stop strip (12) is abutted against the polyethylene caulking plate (17), the space between the polyethylene caulking plate (17) and the "concave" shaped trough body is filled with acrylic mortar (18), and the top surface of the polyethylene caulking plate (17) located in the "concave" shaped trough body is sealed by a polysulfide sealing paste (13).

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