Construction method for water stop structure between new concrete structure and old concrete structure

Abstract

The invention discloses a construction method for a water stop structure between a new concrete structure and an old concrete structure. Comprising the steps that (1) a mounting groove is dug in the side face of an old concrete structure; (2) a wing piece on one side of a conventional water stop piece is pre-bent; (3) the bent wing piece of the water stop piece is fixed to the lower side wall of the mounting groove; (4) a new concrete structure is constructed on one side of the old concrete structure, and the other wing piece of the water stop piece is fixed; and the inlet of the new and old structure parting is filled with sealant. A stressed steel bar layer on the upstream face is avoided by grooving the side face of the old concrete structure, the defect that steel bars are cut off due to grooving is overcome, and the stress strength of the original structure is not affected; the water stop belt is obliquely fixed in the side face groove, then the high-strength cement mortar is backfilled, the intersection position of the backfill material and the side face groove avoids the upstream face, the water stop belt is not prone to being damaged after long-term operation, construction is easy, the structure is safe and reliable, the water stop effect is good, and the water stop belt is very suitable for danger removal, reinforcement, transformation and lifting of water conservancy projects.

Description

Technical Field

[0001] The invention relates to the technical field of water conservancy engineering, and in particular to a construction method of a water-stop structure between new and old concrete structures. Background Art

[0002] my country's Ministry of Water Resources has made every effort to promote the construction of water conservancy infrastructure. After long-term operation, most water conservancy projects have now entered the stage of risk removal, reinforcement, renovation and upgrading. In actual work, a safety appraisal is usually carried out first, and the qualified old concrete structure is retained. Then, a new concrete structure is constructed on this basis. A water-stop structure must be set at the joints between the new and old concrete mentioned above, and the quality of the water-stop structure treatment directly affects the quality, safety and benefits of the project. There are mainly two ways to set up water stops: the first is to cut a rectangular groove 2' on the water-facing surface of the old concrete structure 1', and then install the water-stop plate 3' at the joints between the new and old concrete (see Figure 1 , 2 ); The second method is to attach and fix one end of the water stop sheet 3' to the surface of the old concrete 1' joint, and pour the other end into the new concrete structure 4' (see Figure 3 , 4 ). The former will cut off the steel bars of the concrete surface layer, affecting the safety of the original structure. In addition, the contact surface between the newly poured concrete and the old concrete at the slot is relatively weak, and is more likely to be damaged under the long-term action of water flow, thus causing damage to the waterstop structure and affecting the safety of the project. Although the latter will not cause significant damage to the old structure, since the waterstop is not buried in the concrete, but is attached to the joint through anchor bolts and other measures, if the sealant on the joint surface is aged and damaged after long-term use, the waterstop and the structural joint surface will form a weak point of seepage, and the waterstop cannot play a secondary protective role, affecting the safety and benefits of the project. Summary of the invention

[0003] In order to solve the above problems, the present invention provides a simple, easy, safe and reliable method for constructing a water-stop structure between new and old concrete structures, which can specifically adopt the following technical solutions: The method for constructing a water-stop structure between an old and new concrete structure of the present invention comprises an old concrete structure, a new concrete structure and a water-stop sheet arranged therebetween; the old concrete structure and the new concrete structure are arranged side by side, and the water-facing surfaces of the old concrete structure and the new concrete structure are both provided with a fastening steel bar layer; a mounting groove is provided on the side of the old concrete structure, the opening of the mounting groove is arranged opposite to the joint between the new and old structures, the mounting groove is located below the fastening steel bar layer, and the lower side wall of the mounting groove is a planar structure gradually inclined downward in the direction of the joint between the new and old structures; the water-stop nose of the water-stop sheet is arranged in the joint between the new and old structures, one side wing of the water-stop sheet is attached to the lower side wall and fixedly connected thereto, and the other side wing of the water-stop sheet is arranged in the new concrete structure; a cement mortar backfill layer is provided in the mounting groove, and a sealant sealing layer is provided at the entrance of the joint between the new and old structures; The construction method comprises the following steps: Step 1: Dig the installation groove on the side of the old concrete structure; Step 2: Pre-bend one side wing of the conventional water stop according to the angle between the lower side wall of the installation groove and the joint between the new and old structures; Step 3: Fix the bent water stop wing on the lower side wall of the installation groove; Step 4: Lay closed-cell foam board at the joint between the new and old structures, then construct the new concrete structure on one side of the old concrete structure, and fix the wing piece on the other side of the water stop piece in the new concrete structure; Step 5: Use the grouting pipe to inject high-grade cement mortar into the installation groove for backfilling, and fill the sealant at the entrance of the joint between the new and old structures.

[0004] The seam between the new and old structures is perpendicular to the water-facing surface.

[0005] The cross section of the installation groove is an isosceles right triangle structure with the bottom side parallel to the seam between the new and old structures.

[0006] The water stop plate is a 1.0 mm thick red copper water stop plate.

[0007] A lower gasket, the water stop plate, an upper gasket and a pressing steel plate are arranged in sequence above the lower side wall, and the lower gasket, the water stop plate, the upper gasket and the pressing steel plate are connected to the old concrete structure through anchor bolts.

[0008] The water-stop structure construction method provided by the present invention for use between new and old concrete structures avoids the stressed steel bar layer on the water-facing surface by slotting the side of the old concrete structure, avoids the drawback of cutting off the steel bars due to slotting, and does not affect the stress strength of the original structure; the water-stop strip is tilted and fixed in the side groove, and then backfilled with high-strength cement mortar, and the junction of the backfill material and the side groove avoids the water-facing surface, and is not easily damaged under long-term operation. The present invention is easy to construct, has a safe and reliable structure, is stable and durable, and has a good water-stopping effect, and is very suitable for risk removal, reinforcement, and transformation and improvement of water conservancy projects. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 Is the installation intention of the existing water stop Figure 1 .

[0010] Figure 2 yes Figure 1 Schematic diagram of the structure of the water stop plate.

[0011] Figure 3 Is the installation intention of the existing water stop Figure 2 .

[0012] Figure 4 yes Figure 3 Schematic diagram of the structure of the water stop plate.

[0013] Figure 5 It is a schematic structural diagram of the water-stopping structure of the present invention (the closed-cell foam board is omitted).

[0014] Figure 6 yes Figure 5 Schematic diagram of the structure of the water stop plate.

[0015] Figure 7 yes Figure 5 A partial enlarged view of the anchor bolt part. DETAILED DESCRIPTION

[0016] The following is a detailed description of an embodiment of the present invention in conjunction with the accompanying drawings. This embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation method and a specific operation process are given, but the protection scope of the present invention is not limited to the following embodiment.

[0017] like Figure 5-7 As shown, the water-stopping structure used between the new and old concrete structures of the present invention comprises an old concrete structure 1, a new concrete structure 2 and a water-stopping sheet 3 arranged therebetween.

[0018] The old concrete structure 1 and the new concrete structure 2 are arranged side by side. In this embodiment, the joints between the two (i.e., the joints 4 between the old and new structures) are perpendicular to the water-facing surface. The water-facing surfaces of the old concrete structure 1 and the new concrete structure 2 are both provided with stress-bearing steel bars and distribution steel bars (forming a fastening steel bar layer 5) according to the stress conditions of the structures to meet the safety requirements of the concrete structures.

[0019] The side of the old concrete structure 1 (i.e., the side close to the joint 4 between the new and old structures) is provided with an installation groove 6, which is located below the fastening steel bar layer 5, and the opening of the installation groove 6 is arranged opposite to the joint 4 between the new and old structures, and the lower side wall of the installation groove 6 is a plane structure that gradually tilts downward in the direction of the joint 4 between the new and old structures. In this embodiment, the cross section of the installation groove 6 is an isosceles right triangle structure whose bottom side is parallel to the joint 4 between the new and old structures, that is, the upper side wall of the installation groove 6 is arranged 45° upward along its symmetry axis, and the lower side wall is arranged 45° downward along its symmetry axis. Therefore, when installing the water stop sheet 3, it is only necessary to fold one side of the wing upward by 45°, which is convenient and easy. In addition, when the wing of the water stop sheet 3 is attached to the lower side wall, if water seepage occurs, it will converge along the wing to the water stop nose of the water stop sheet 3 (i.e., the U-shaped bend in the middle of the water stop sheet 3), thereby improving the water blocking effect.

[0020] The above-mentioned water stop plate 3 adopts a 1.0mm thick copper water stop plate, wherein the central water stop nose is arranged in the joint 4 between the new and old structures, one side wing plate is attached to the lower side wall of the installation groove 6 and fixedly connected thereto, and the other side wing plate is poured into the new concrete structure 2 during construction.

[0021] The water stop plate 3 is connected to the old concrete structure 1 by anchoring. Specifically, a lower gasket 7 is arranged above the lower side wall of the installation groove 6, and then the water stop plate 3, the upper gasket 8 and the pressing steel plate 9 are placed in sequence, and then the lower gasket 7, the water stop plate 3, the upper gasket 8 and the pressing steel plate 9 are fixed to the old concrete structure 1 by anchor bolts 10. The upper gasket 8 and the lower gasket 7 are usually rubber gaskets, the pressing steel plate 9 is Q235 steel plate, and multiple anchor bolts 10 are evenly spaced in the length direction of the installation groove 6.

[0022] After the construction of the new concrete structure 2 is completed, high-grade cement mortar (the required strength is higher than that of the old concrete structure 1) is injected into the installation groove 6 through the grouting pipe to form a cement mortar backfill layer 11, and sealant is filled at the entrance of the new and old structure joints 4 to form a sealant sealing layer 12.

[0023] Taking a conventional 420 mm wide copper sheet water stop as an example, the construction method of the water stop structure of the present invention is described, which specifically includes the following steps: Step 1: excavate an isosceles right triangle groove with a bottom width of 317 mm and a height of 158 mm on the side of the old concrete structure 1 as the installation groove 6; Step 2: Make or purchase a 1.0 mm thick copper water stop sheet 3 with a water stop nose, bend one side of the wing upwards by 45° and set aside; Step 3: Use anchor bolts 10 to fix the bent wing of the water stop 3 to the lower side wall of the installation groove 6; specifically, ① drill holes every 300mm on the lower side wall of the installation groove 6, with a hole depth of 350mm; ② place the rubber lower gasket 7, the copper sheet water stop 3, the rubber upper gasket 8 and the 100mm×8mm Q235 compression steel plate 9 with reserved holes in sequence above the lower side wall of the installation groove 6; ③ Use anchor bolts 10 to fix the lower gasket 7, the water stop 3, the upper gasket 8 and the compression steel plate 9 to the old concrete structure 1, and inject anchor glue into the drilled holes; Step 4: Lay out a closed-cell foam board at the joint 4 between the new and old structures, then construct a new concrete structure 2 on one side of the old concrete structure 1, and fix the wing piece on the other side of the water stop sheet 3 in the new concrete structure 2; Step 5: Use a grouting pipe to inject high-grade cement mortar into the installation groove 6 for backfilling, and fill the sealant at the entrance of the joint between the new and old structures.

[0024] It should be noted that, in the description of the present invention, terms indicating orientation or positional relationships, such as "front", "rear", "left", "right", "vertical", "horizontal", "inside", "outside", etc., are based on the orientation or positional relationships shown in the drawings and are only for the convenience of describing the present invention and simplifying the description, 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.

Claims

1. A method for constructing a water-stop structure between new and old concrete structures, characterized in that: The water-stop structure comprises an old concrete structure, a new concrete structure and a water-stop sheet arranged therebetween; the old concrete structure and the new concrete structure are arranged side by side, and the water-facing surfaces of the old concrete structure and the new concrete structure are both provided with a fastening steel bar layer; a mounting groove is provided on the side of the old concrete structure, the opening of the mounting groove is arranged opposite to the joint between the new and old structures, the mounting groove is located below the fastening steel bar layer, and the lower side wall of the mounting groove is a plane structure gradually inclined downward in the direction of the joint between the new and old structures; the water-stop nose of the water-stop sheet is arranged in the joint between the new and old structures, one side wing of the water-stop sheet is attached to the lower side wall and fixedly connected thereto, and the other side wing of the water-stop sheet is arranged in the new concrete structure; a cement mortar backfill layer is provided in the mounting groove, and a sealant sealing layer is provided at the entrance of the joint between the new and old structures; The construction method comprises the following steps: Step 1: Dig the installation groove on the side of the old concrete structure; Step 2: Pre-bend one side wing of the conventional water stop according to the angle between the lower side wall of the installation groove and the joint between the new and old structures; Step 3: Fix the bent water stop wing on the lower side wall of the installation groove; Step 4: Lay closed-cell foam board at the joint between the new and old structures, then construct the new concrete structure on one side of the old concrete structure, and fix the wing piece on the other side of the water stop piece in the new concrete structure; Step 5: Use the grouting pipe to inject high-grade cement mortar into the installation groove for backfilling, and fill the sealant at the entrance of the joint between the new and old structures.

2. The method for constructing a water-stop structure between new and old concrete structures according to claim 1, characterized in that: The seam between the new and old structures is perpendicular to the water-facing surface.

3. The method for constructing a water-stop structure between new and old concrete structures according to claim 1, characterized in that: The cross section of the installation groove is an isosceles right triangle structure with the bottom side parallel to the seam between the new and old structures.

4. The method for constructing a water-stop structure between new and old concrete structures according to claim 1, characterized in that: The water stop plate is a 1.0 mm thick red copper water stop plate.

5. The method for constructing a water-stop structure between new and old concrete structures according to claim 1, characterized in that: A lower gasket, the water stop plate, an upper gasket and a pressing steel plate are arranged in sequence above the lower side wall, and the lower gasket, the water stop plate, the upper gasket and the pressing steel plate are connected to the old concrete structure through anchor bolts.

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