Positioning device for concrete beam prestressed beam steel strand support tube
By using flexible plastic support tubes and U-shaped sleeves combined with a vertical bracing adjustment mechanism in concrete beams, the problems of positional accuracy and stability of the support tubes were solved, thus improving the tensioning construction quality of prestressed steel strands.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- CHINA CONSTR SEVENTH ENG DIVISION CORP LTD
- Filing Date
- 2025-05-22
- Publication Date
- 2026-06-26
AI Technical Summary
In existing prestressed concrete beams, the positional accuracy and stability of the steel strand threading support pipes are not high, which affects the quality of tensioning construction.
The system uses easily bendable plastic support tubes, combined with U-shaped sleeves and vertical bracing adjustment mechanisms. The support tubes are fixed by the U-shaped sleeves and the height is finely adjusted by the vertical bracing adjustment mechanism to ensure the stability and positional accuracy of the support tubes within the steel reinforcement system.
This improved the assembly stability and positional accuracy of the support pipe, thereby enhancing the tensioning quality of the prestressed steel strands.
Smart Images
Figure CN224413157U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of prestressed beams, and in particular to a positioning device for the steel strand support pipe of a prestressed concrete beam. Background Technology
[0002] Prestressed concrete beams are constructed by applying a certain amount of pressure to the beam before it is subjected to load. This pressure allows the tensile stress generated during the service life to first offset the prestress, thereby delaying the appearance of cracks and limiting their width. Prestressed concrete beams improve the beam's crack resistance. Under the same load-bearing capacity requirements, the cross-sectional height of a prestressed beam can be smaller than that of a conventional concrete beam, thus reducing the structure's self-weight and lowering foundation costs. Furthermore, it increases the beam's stiffness and reduces deformation during service life, resulting in better structural stability and applicability.
[0003] Prestressed beams require the installation and tensioning of prestressed steel strands. The elastic recoil force of the reinforcing steel instills prestress into the concrete beam. To ensure the smooth insertion of the steel strands, vertically curved support tubes are installed within the reinforcing steel system. Currently, these support tubes are typically fixed using wire binding, which can lead to inaccurate positioning and poor stability, affecting the quality of the prestressing strand tensioning process and requiring improvement. Utility Model Content
[0004] To address the aforementioned problems, this utility model proposes a positioning device for the steel strand support pipe of a prestressed concrete beam.
[0005] The technical solution of this utility model is: a positioning device for steel strand support pipes of prestressed concrete beams, comprising a beam reinforcement system and support pipes. The support pipes are easily bendable plastic pipes and are arranged in an S-shape within the beam reinforcement system. Multiple support pipes can be arranged side by side in the beam reinforcement system. The support pipes are supported on the transverse reinforcement bars within the beam reinforcement system. A U-shaped sleeve is provided at the transverse reinforcement bar, and the U-shaped sleeve is welded and fixed to the middle of the transverse reinforcement bar in the opposite direction. The support pipe passes through the U-shaped sleeve, and a sliding gap is provided between the support pipe and the U-shaped sleeve, allowing the support pipe to slide freely within the U-shaped sleeve while also restricting its large displacement. A vertical support adjustment mechanism connected to the support pipe is provided between adjacent transverse reinforcement bars.
[0006] Preferably, the vertical support adjustment mechanism includes a vertical support rod and an L-shaped bracket. A horizontal support rod is vertically provided at the lower part of the vertical support rod, and both ends of the horizontal support rod are fixed to the longitudinal bars of the beam reinforcement system. A sliding sleeve is provided at the end of the L-shaped bracket, and the sliding sleeve is slidably connected to the middle part of the vertical support rod. The L-shaped bracket can rotate and slide on the vertical support rod through the sliding sleeve. The L-shaped bracket supports the support tube, and the width of the L-shaped bracket matches the size of the support tube. Adjusting nuts are threadedly connected to the vertical support rod at the upper and lower parts of the sliding sleeve.
[0007] Preferably, at least two horizontal braces are arranged side by side, and the distance between the two horizontal braces is the same as the distance between adjacent longitudinal ribs.
[0008] Preferably, two U-shaped sleeves are arranged side by side, and the two U-shaped sleeves are welded parallel to each other to the outer side of the transverse rib, with the height of one U-shaped sleeve being higher than the height of the other U-shaped sleeve.
[0009] Preferably, the end of the support tube is fitted with a pre-embedded sleeve, which is made of stainless steel. The pre-embedded sleeve has a limiting end plate on its cross-section, and each of the four corners of the limiting end plate has a through hole for inserting a rivet. The pre-embedded sleeve and the support tube can slide relative to each other.
[0010] Preferably, a spring is fitted onto the embedded sleeve, and the spring is welded and fixed to the embedded sleeve. Both the spring and the embedded sleeve extend into the beam reinforcement system to a certain depth.
[0011] The beneficial technical effects of this utility model are as follows: This utility model fixes the support pipe by setting a double U-shaped sleeve on the transverse reinforcement of the steel reinforcement system, which has the advantage of high support strength for the support pipe and improves its assembly stability. At the same time, a vertical support adjustment mechanism is set in the steel reinforcement system. The height of the support pipe is finely adjusted by the mechanism to assist in supporting the support pipe and improve its position accuracy, thereby improving the prestressing tensioning construction quality of the prestressed steel strand. Attached Figure Description
[0012] Figure 1 This is a three-dimensional structural schematic diagram of the present invention;
[0013] Figure 2 yes Figure 1 A magnified view of a portion of the image;
[0014] Figure 3 This is a schematic diagram of the main structure of this utility model;
[0015] Figure 4 yes Figure 3 A schematic diagram of the AA-direction cross-section structure;
[0016] Figure 5 This is a three-dimensional structural diagram of the vertical support adjustment mechanism.
[0017] In the figure, 1. Beam reinforcement system, 11. Longitudinal reinforcement, 12. Transverse reinforcement, 2. Support pipe, 3. U-shaped sleeve, 4. Vertical support adjustment mechanism, 41. Vertical support rod, 42. Horizontal support rod, 43. L-shaped bracket, 431. Sliding sleeve, 44. Adjusting nut, 5. Embedded sleeve, 51. Limiting end plate, 6. Spring. Detailed Implementation
[0018] Example 1, see appendix Figure 1-4A positioning device for a prestressed concrete beam steel strand support pipe includes a beam reinforcement system 1 and a support pipe 2. The support pipe is S-shaped and installed within the beam reinforcement system. The support pipe 2 is supported on transverse reinforcement bars 12 within the beam reinforcement system 1. A U-shaped sleeve 3 is provided at each transverse reinforcement bar 12. The U-shaped sleeve 3 is welded in the opposite direction and fixed to the middle of the transverse reinforcement bar 12. The support pipe 2 passes through the U-shaped sleeve 3, and a sliding gap is provided between the support pipe 2 and the U-shaped sleeve 3 to ensure that it can be pulled outward after the initial setting of the concrete. By setting double U-shaped sleeves 3 on the transverse reinforcement bars 12 of the reinforcement system to fix the support pipe 2, it has the advantage of high support strength for the support pipe and improves its assembly stability. A vertical bracing adjustment mechanism 4 connected to the support pipe 2 is provided between adjacent transverse reinforcement bars 12.
[0019] Two U-shaped sleeves 3 are arranged side by side, and the two U-shaped sleeves 3 are welded parallel to each other on the outer side of the transverse rib 12. The double U-shaped sleeves 3 have a large limiting support area for the support tube 2, and the fixing effect is better.
[0020] The end of the support pipe 2 is fitted with a pre-embedded sleeve 5. The cross-section of the pre-embedded sleeve is provided with a limiting end plate 51. The pre-embedded sleeve 5 and the support pipe 2 can slide relative to each other. The limiting end plate 51 is supported on the end face of the beam, increasing the anchoring force of the pre-embedded sleeve 5, so that the pre-embedded sleeve 5 provides strong sliding support for the subsequent insertion of steel strands.
[0021] A spring 6 is fitted onto the embedded sleeve 5. The spring is welded and fixed to the embedded sleeve 5. After the concrete is poured, the spring 6 can be evenly embedded into the concrete, thereby improving the bonding strength between the embedded sleeve 5 and the beam concrete.
[0022] The construction process and principle of the positioning device for the prestressed steel strand support pipe 2 in this embodiment are as follows: According to the design requirements of the prestressed steel strand, U-shaped sleeves 3 are welded and fixed on the transverse reinforcement 12 in the beam reinforcement system 1, and vertical support adjustment mechanisms 4 are set between adjacent U-shaped sleeves 3. After the U-shaped sleeves 3 are welded, the support pipe 2 is inserted into the reinforcement system from one end. The support pipe 2 passes through each U-shaped sleeve 3 in sequence according to the bending route. At the same time, the vertical support adjustment mechanism 4 assists in supporting the support pipe 2, and the support pipe 2 forms a fixed bending shape. Then, the subsequent concrete pouring construction is carried out. Before the concrete initially sets, the internal support pipe 2 is pulled out, so that a channel for the steel strand to pass through is formed inside the beam.
[0023] Example 2, see appendix Figure 3-5This embodiment is basically the same as Embodiment 1, and the similarities will not be repeated. The difference is that the vertical support adjustment mechanism 4 includes a vertical support rod 41 and an L-shaped bracket 43. A horizontal support rod 42 is vertically provided at the lower part of the vertical support rod 41. The two ends of the horizontal support rod are fixed to the longitudinal bars 11 of the beam reinforcement system 1, which vertically fixes the entire vertical support adjustment mechanism 4 in the reinforcement system. A sliding sleeve 431 is provided at the end of the L-shaped bracket 43. The sliding sleeve is slidably connected to the middle part of the vertical support rod 41. The L-shaped bracket 43 supports the support tube 2. The gap between the L-shaped bracket 43 and the vertical support rod 41 matches the size of the support tube 2. Adjusting nuts 44 are threadedly connected to the vertical support rod 41 at the upper and lower parts of the sliding sleeve 431. At least two horizontal support rods 42 are arranged side by side.
[0024] In this embodiment, the vertical support adjustment mechanism 4 uses an L-shaped bracket 43 to assist in supporting the support pipe 2, thereby improving its stability within the steel reinforcement system. By turning the adjusting nut 44, the sliding sleeve 431 can be driven to slide along the vertical support rod 41, changing the height of the L-shaped bracket 43 and thus changing its support height for the support pipe 2, keeping it in an accurate bending and fixing position. The vertical support adjustment mechanism 4, which is evenly distributed within the steel reinforcement system, can ensure the bending accuracy of each part of the support pipe 2 and improve its construction quality.
Claims
1. A positioning device for steel strand support pipes in prestressed concrete beams, characterized in that: It includes a beam reinforcement system and a support pipe. The support pipe is S-shaped and installed inside the beam reinforcement system. The support pipe is supported on the transverse reinforcement bars inside the beam reinforcement system. A U-shaped sleeve is provided at the transverse reinforcement bar. The U-shaped sleeve is welded in the opposite direction and fixed to the middle of the transverse reinforcement bar. The support pipe passes through the U-shaped sleeve and there is a sliding gap between the support pipe and the U-shaped sleeve. A vertical bracing adjustment mechanism connected to the support pipe is provided between adjacent transverse reinforcement bars.
2. The positioning device for the steel strand support pipe of a prestressed concrete beam according to claim 1, characterized in that: The vertical support adjustment mechanism includes a vertical support rod and an L-shaped bracket. A horizontal support rod is vertically provided at the lower part of the vertical support rod. The two ends of the horizontal support rod are fixed to the longitudinal bars of the beam reinforcement system. A sliding sleeve is provided at the end of the L-shaped bracket. The sliding sleeve is slidably connected to the middle part of the vertical support rod. The L-shaped bracket supports the support tube. Adjusting nuts are threadedly connected to the vertical support rod at the upper and lower parts of the sliding sleeve.
3. The positioning device for the steel strand support pipe of a prestressed concrete beam according to claim 2, characterized in that: The cross braces are arranged in at least two parallel sections.
4. The positioning device for the steel strand support pipe of a prestressed concrete beam according to claim 1, characterized in that: The U-shaped sleeves are arranged side by side, and the two U-shaped sleeves are welded parallel to each other to the outer side of the transverse rib.
5. The positioning device for the steel strand support pipe of a prestressed concrete beam according to claim 1, characterized in that: The end of the support pipe is fitted with a pre-embedded sleeve, and a limiting end plate is provided on the cross-section of the pre-embedded sleeve, allowing the pre-embedded sleeve and the support pipe to slide relative to each other.
6. The positioning device for the steel strand support pipe of a prestressed concrete beam according to claim 5, characterized in that: A spring is fitted onto the pre-embedded sleeve, and the spring is welded and fixed to the pre-embedded sleeve.