PC cast-in-situ aqueduct structure with longitudinal steel beams tensioned at single end
By using longitudinal steel strands with single-end tensioning and a waterproof coating in the aqueduct structure, the problems of cumbersome construction and water leakage of single-end tensioned PC cast-in-place aqueducts were solved, achieving efficient casting and improved durability.
Patent Information
- Application Number
- CN202422832463.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-20
- Publication Date
- 2025-11-04
- Estimated Expiration
- 2034-11-20
AI Technical Summary
The existing construction process of single-end tensioned PC cast-in-place aqueduct is complicated, the end concrete is not densely poured, and there is a risk of water leakage.
The PC cast-in-place aqueduct structure adopts longitudinal steel strands with single-end tensioning. The aqueduct body is divided into anchoring end section, transition section, standard section and tensioning end section along the length direction. It is equipped with longitudinal and circumferential steel strands. The tensioning end section is equipped with a waterstop groove. Concrete pouring is carried out from top to bottom. The exposed surface of the aqueduct body is coated with a waterproof coating.
The construction process of the aqueduct was simplified, the quality of concrete pouring was ensured, and the durability and waterproof performance of the aqueduct were improved.
Smart Images
Figure CN223510258U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to the field of hydraulic engineering, concretely is a kind of prestressed prestressed cast-in-situ flume structure with longitudinal steel beam using single-end tension. BACKGROUND
[0002] Flume is a kind of overhead water channel acrossing valley, line. Flume is a kind of water conveyance building, with the development of hydraulic engineering, simply supported flume is developed towards prestressed system with large span and high bearing capacity, flume uses prestressed concrete structure (Prestressed Concrete), so it is called PC flume. At present, simply supported PC cast-in-situ flume uses double-end tension or single-end tension to establish prestress, so as to reach the required design bearing capacity.
[0003] The end cross section of the existing single-end tension PC cast-in-situ flume is shown in Figure 1 The distribution of post-cast strip notch 1 at the end of flume on cross section is not continuous, and the shape of post-cast strip notch 1 is very complex. During construction, smaller formwork is needed to seal the end concrete, and anchor bolt for water stop needs to be pre-buried at the position without post-cast strip notch, and anchor bolt needs to be buried before pouring secondary concrete at the position with post-cast strip notch, so the whole construction process is relatively complicated; the concrete at the position of post-cast strip notch part can only be poured horizontally, and the problems of non-dense pouring and non-dense vibration are prone to occur. INVENTION CONTENTS
[0004] The utility model provides a kind of PC cast-in-situ flume structure with longitudinal steel beam using single-end tension, to simplify the end structure of existing flume, simplify the construction of flume.
[0005] The technical scheme adopted by the utility model is: a kind of PC cast-in-situ flume structure with longitudinal steel beam using single-end tension, the length direction of flume is sequentially for anchoring end head section, first gradual change section, standard section, second gradual change section and tension end head section in the length direction of flume, and continuous water passage is formed in the inner side of each section;Ring beam and longitudinal steel beam are provided in the body of flume, each longitudinal steel beam is arranged along the length direction of flume, and the end face of tension end head section is provided with longitudinal steel beam tension groove, longitudinal steel beam tension groove is continuously distributed on the section perpendicular to the length direction of flume, longitudinal steel beam tension groove extends to the top surface of two side walls of the water passage of tension end head section, and the anchoring end of each longitudinal steel beam is anchored in anchoring end head section, and the tension end of each longitudinal steel beam is located in longitudinal steel beam tension groove.
[0006] After the aqueducts are prestressed through tensioning, anchorage reinforcement bars are laid between the anchorage end sections and tensioning end sections of adjacent aqueducts, and then concrete is poured to form a joint structure. To facilitate the installation of a water-stop structure and prevent leakage at the joint, the end face of the anchorage end section and the end face of the tensioning end section are both provided with a water-stop groove along the water passage. The water-stop grooves on the end face of the tensioning end section are located inside the longitudinal steel strand tensioning groove.
[0007] To ensure a stable connection between the subsequently poured concrete and the end face of the aqueduct, the end faces of both the anchoring end section and the tensioning end section are roughened by chiseling.
[0008] The two ends of the aqueduct need to be placed on top of two supports. Specifically: the bottom surfaces of the anchoring end section and the tensioning end section are both horizontal planes and form end beams respectively.
[0009] To further improve the waterproof performance of the tank, the surfaces of the tank that form water passages are coated with a waterproof coating, or all exposed surfaces of the tank are coated with a waterproof coating. For example, the waterproof coating is a cement-based penetrating crystalline waterproof coating with a thickness of 2 mm.
[0010] In order to apply circumferential prestress to the steel strands through double-end tensioning rings, furthermore: the planes corresponding to each circumferential steel strand are perpendicular to the length direction of the aqueduct and are arranged at intervals along the length direction of the aqueduct. The top of the two side walls of each section of the aqueduct is provided with circumferential steel strand tensioning grooves, and the two ends of the circumferential steel strands are located in the two circumferential steel strand tensioning grooves.
[0011] To further improve the stability of the aqueduct, the water passage has a U-shaped cross-section perpendicular to the length of the aqueduct, and the tops of the two side walls of each section of the aqueduct are connected by tie rods spaced apart along the length of the aqueduct.
[0012] To ensure the safety of personnel walking on the top of the two side walls of the trough, additionally, pedestrian railings are installed on the top of the two side walls of each section of the trough.
[0013] To further reduce the stress of the circumferential steel strands on the channel body, the circumferential steel strands are flat in cross-section.
[0014] The beneficial effects of this invention are as follows: the longitudinal steel strand tensioning channels are continuously distributed on a cross-section perpendicular to the length direction of the aqueduct, and the end face shape of the tensioning end section is relatively simple, making it easier to erect the formwork for the end face of the tensioning end section when pouring the aqueduct body. After the longitudinal steel strands are prestressed through tensioning, concrete can be poured into the longitudinal steel strand tensioning channels from top to bottom without affecting the vibration of the concrete, ensuring the pouring quality, and thus guaranteeing the durability of the aqueduct. Attached Figure Description
[0015] Figure 1 This is a schematic diagram of the end cross-section of an existing single-end tensioned PC cast-in-place aqueduct.
[0016] Figure 2 This is a schematic diagram of the tank structure of this utility model.
[0017] Figure 3 yes Figure 2 A schematic diagram of the end face of the anchoring end section in the embodiment shown.
[0018] Figure 4 yes Figure 2 A cross-sectional schematic diagram of the standard segment of the embodiment shown.
[0019] Figure 5 yes Figure 2 A schematic diagram of the end face of the tensioning end section in the embodiment shown.
[0020] Figure reference numerals: 1. Post-cast strip groove; 2-1. Anchorage end section; 2-2. First transition section; 2-3. Standard section; 2-4. Second transition section; 2-5. Tensioning end section; 3. Water passage; 4. Circumferential steel strand; 5. Longitudinal steel strand; 6. Longitudinal steel strand tensioning groove; 7. Waterstop groove; 8. Circumferential steel strand tensioning groove; 9. Tie rod. Detailed Implementation
[0021] The present invention will be further described below with reference to the accompanying drawings.
[0022] like Figures 2 to 5 As shown, this utility model is a cast-in-place PC aqueduct structure with longitudinal steel strands tensioned at one end. The aqueduct body, along its length, consists of an anchoring end section 2-1, a first transition section 2-2, a standard section 2-3, a second transition section 2-4, and a tensioning end section 2-5. Each section forms a continuous water-passing channel 3 on its inner side, with the water flow direction of the water-passing channel 3 consistent with the length direction of the aqueduct. Each section of the aqueduct is a reinforced concrete structure and is a single unit. The cross-section of the water-passing channel 3 perpendicular to the length direction of the aqueduct is generally U-shaped, but can also be C-shaped. To enhance the stability of the aqueduct body, the tops of the two side walls of each section are connected by tie rods 9 spaced apart along the length direction of the aqueduct. The two side walls of the aqueduct body are also the two side walls of the water-passing channel 3. The tie rods 9 are generally reinforced concrete structures and are cast integrally with the aqueduct body. The length direction of the tie rods 9 is perpendicular to the length direction of the aqueduct, and the tie rods 9 are generally evenly spaced. To ensure the safety of personnel walking on the top of the two side walls of the trough, pedestrian railings are also installed on the top of the two side walls of each section of the trough.
[0023] The aqueduct body contains circumferential steel strands 4 and longitudinal steel strands 5. The planes corresponding to each circumferential steel strand 4 are perpendicular to the length of the aqueduct and are spaced apart along its length. Circumferential steel strand tensioning grooves 8 are respectively provided at the top of the two side walls of each section of the aqueduct body, with both ends of the circumferential steel strand 4 located within the two circumferential steel strand tensioning grooves 8. Circumferential prestress can be established in the circumferential steel strands 4 through double-end tensioning or single-end tensioning. After the circumferential prestress is established in the circumferential steel strands 4, concrete can be poured into the circumferential steel strand tensioning grooves 8. Due to the large length of the aqueduct body, i.e., the large span of the aqueduct, the aqueduct body is actually a thin-walled component. To reduce the stress of the circumferential steel strands 4 on the aqueduct body, the circumferential steel strands 4 are flat in cross-section to increase the contact area between the circumferential steel strands 4 and the aqueduct body. For example, the circumferential steel strands 4 use flat-anchored high-strength, low-relaxation steel strands 7Φ. s 15.2, and adopts a double-end tensioning process.
[0024] There are multiple longitudinal steel strands 5, each arranged along the length of the aqueduct. The two ends of each longitudinal steel strand 5 are the anchoring end and the tensioning end, respectively. The end face of the tensioning end section 2-5 of the aqueduct body is provided with longitudinal steel strand tensioning grooves 6. These grooves are continuously distributed on a cross-section perpendicular to the length of the aqueduct, such as... Figure 5 As shown. The longitudinal steel strand tensioning groove 6 extends to the top surface of the two side walls of the water passage 3 in the tensioning end section 2-5, to facilitate the later pouring and vibration of concrete into the longitudinal steel strand tensioning groove 6. The depth of the longitudinal steel strand tensioning groove 6 only needs to meet the construction conditions, for example, a depth of 0.2m to 0.4m. The anchoring ends of each longitudinal steel strand 5 are anchored in the anchoring end section 2-1, and the tensioning ends of each longitudinal steel strand 5 are located in the longitudinal steel strand tensioning groove 6. The outer boundary of the longitudinal steel strand tensioning groove 6 is set along the arrangement boundary of each longitudinal steel strand 5. In order to ensure that the anchoring ends of the longitudinal steel strand 5 are firmly anchored in the anchoring end section 2-1, the anchoring ends of the longitudinal steel strand 5 have end plates, which are embedded in the anchoring end section 2-1. According to the stress of the longitudinal steel strand 5, the longitudinal steel strand 5 generally uses steel strands with a circular cross-section, for example, the longitudinal steel strand 5 uses high-strength, low-relaxation steel strand 7Φ with circular anchors. s 15.2, and adopts single-end tensioning process.
[0025] The two ends of the aqueduct need to be placed on top of two supports; therefore, the bottom surfaces of both the anchoring end section 2-1 and the tensioning end section 2-5 are horizontal and form end beams respectively. See, for example... Figure 3 and Figure 5 The outer contours of the anchoring end section 2-1 and the tensioning end section 2-5 are rectangular at the top and isosceles trapezoidal at the bottom in the cross section perpendicular to the length direction of the aqueduct.
[0026] After the aqueducts are prestressed through tensioning, anchorage reinforcement bars are laid and concrete is poured between the anchorage end section 2-1 and the tensioning end section 2-5 of two adjacent aqueducts, thus forming a joint structure. To facilitate the installation of a water-stop structure and prevent leakage at the joint, a water-stop groove 7 is provided on the end face of the anchorage end section 2-1 along the water passage 3, and a water-stop groove 7 is also provided on the end face of the tensioning end section 2-5 along the water passage 3. The water-stop groove 7 on the end face of the tensioning end section 2-5 is located inside the longitudinal steel strand tensioning groove 6. (See [reference]). Figure 3 and Figure 5 To ensure a stable connection between the subsequently poured concrete and the end face of the aqueduct, the end faces of both the anchoring end section 2-1 and the tensioning end section 2-5 are roughened surfaces, for example, with a roughening depth of 6mm. The side wall of the longitudinal steel strand tensioning groove 6, away from the water passage 3, serves as a template for the pouring of the joint structure.
[0027] The end face of the anchorage end section 2-1 can be a vertical plane perpendicular to the length direction of the aqueduct. Due to the use of single-end tensioning, no pre-reserved space for steel strand tensioning is needed between aqueduct sections. The dimension of the joint structure along the length of the aqueduct can be shortened to 0.4m to 0.8m. Therefore, the supports for the aqueduct body can be moved to both sides of the aqueduct body, reducing the width of the piers and thus saving on the amount of concrete used for the piers. To improve the waterproof performance of the aqueduct body, a waterproof coating is applied to the surface of the aqueduct body forming the water passage 3. To prevent water from seeping into the aqueduct body and extend its service life, all exposed surfaces of the aqueduct body are coated with a waterproof coating. For example, the waterproof coating is a 2mm thick cement-based penetrating crystalline waterproof coating.
Claims
1. A cast-in-place PC aqueduct structure with longitudinal steel strands tensioned at one end, wherein the aqueduct body, along its length, consists of an anchoring end section (2-1), a first transition section (2-2), a standard section (2-3), a second transition section (2-4), and a tensioning end section (2-5), with continuous water passages (3) formed on the inner side of each section; characterized in that: The aqueduct is equipped with circumferential steel strands (4) and longitudinal steel strands (5). Each longitudinal steel strand (5) is arranged along the length of the aqueduct. The end face of the tensioning end section (2-5) is provided with a longitudinal steel strand tensioning groove (6). The longitudinal steel strand tensioning groove (6) is continuously distributed on a section perpendicular to the length of the aqueduct. The longitudinal steel strand tensioning groove (6) extends to the top surface of the two side walls of the water passage (3) of the tensioning end section (2-5). The anchoring end of each longitudinal steel strand (5) is anchored in the anchoring end section (2-1). The tensioning end of each longitudinal steel strand (5) is located in the longitudinal steel strand tensioning groove (6).
2. The PC cast-in-place aqueduct structure with single-end tensioning of longitudinal steel strands as described in claim 1, characterized in that: The end face of the anchoring end section (2-1) is provided with a waterstop groove (7) along the water passage (3), and the end face of the tensioning end section (2-5) is provided with a waterstop groove (7) along the water passage (3). The waterstop groove (7) on the end face of the tensioning end section (2-5) is located inside the longitudinal steel strand tensioning groove (6).
3. The PC cast-in-place aqueduct structure with single-end tensioning of longitudinal steel strands as described in claim 1, characterized in that: The end faces of both the anchoring end section (2-1) and the tensioning end section (2-5) are roughened surfaces treated with chiseling.
4. The PC cast-in-place aqueduct structure with single-end tensioning of longitudinal steel strands as described in claim 1, characterized in that: The bottom surfaces of both the anchoring end section (2-1) and the tensioning end section (2-5) are horizontal and form end beams respectively.
5. A cast-in-place PC aqueduct structure with single-end tensioning of longitudinal steel strands as described in claim 1, characterized in that: The surface of the tank body that forms the water passage (3) is provided with a waterproof coating, or all exposed surfaces of the tank body are provided with a waterproof coating.
6. A cast-in-place PC aqueduct structure with single-end tensioning of longitudinal steel strands as described in claim 5, characterized in that: The waterproof coating is a 2mm thick cement-based penetrating crystalline waterproof coating.
7. A cast-in-place PC aqueduct structure with single-end tensioning of longitudinal steel strands as described in any one of claims 1 to 6, characterized in that: The planes corresponding to each circumferential steel strand (4) are perpendicular to the length direction of the aqueduct and are arranged at intervals along the length direction of the aqueduct. The top of the two side walls of each section of the aqueduct is provided with circumferential steel strand tensioning grooves (8), and the two ends of the circumferential steel strand (4) are located in the two circumferential steel strand tensioning grooves (8).
8. A cast-in-place PC aqueduct structure with single-end tensioning of longitudinal steel strands as described in any one of claims 1 to 6, characterized in that: The water passage (3) has a U-shaped cross section perpendicular to the length of the aqueduct, and the tops of the two side walls of each section of the aqueduct are connected by tie rods (9) arranged at intervals along the length of the aqueduct.
9. A cast-in-place PC aqueduct structure with single-end tensioning of longitudinal steel strands as described in any one of claims 1 to 6, characterized in that: Pedestrian railings are installed at the top of the two side walls of each section of the trough.
10. A cast-in-place PC aqueduct structure with single-end tensioning of longitudinal steel strands as described in any one of claims 1 to 6, characterized in that: The circumferential steel strand (4) has a flat cross-section.