An optimized structure for post-tensioned bonded prestressed tensioning grooves and its construction method.

Abstract

This invention discloses an optimized structure and construction method for a bonded prestressed tensioning channel in post-tensioning. The optimized structure includes a prestressed beam, a tensioning side beam located at one end of the prestressed beam, and tensioning bars located inside the prestressed beam and the tensioning side beam. By setting up the tensioning side beam, this invention extends the tensioning end, originally located at the prestressed beam end, to the tensioning side beam, avoiding the densely reinforced area at the beam end; it also provides a tensioning foundation for prestressing. The tensioning side beam platform and the tensioning side channel beam form a tensioning channel, enabling convenient tensioning and ensuring sufficient operating space for tensioning. The reinforcement of the tensioning end is further ensured by the denser stirrups and diagonally inserted reinforcing bars, which helps to improve the strength of the beam at the tensioning point.

Description

Technical Field

[0001] This invention relates to the field of prestressed beam construction technology, and in particular to an optimized structure for post-tensioned bonded prestressed tensioning grooves and its construction method. Background Technology

[0002] For cast-in-place beam construction, prestressing is often used to ensure improved performance such as strength and cracking resistance during use. Prestressing is divided into pre-tensioning and post-tensioning. Post-tensioning involves inserting reinforcing bars to anchor the beam after it has been cast. However, in actual on-site construction, the main reinforcement bars of beams and columns are often large, and the prestressing tendons are positioned close to the densely reinforced areas at the beam ends. If tensioning slots are pre-reserved using conventional methods, a large number of main reinforcement bars in the beams and columns would need to be cut, making on-site construction difficult. Furthermore, the remaining space in the densely reinforced areas is narrow, making it difficult to arrange reinforcing bars around the tensioning slots. Summary of the Invention

[0003] This invention provides an optimized structure and construction method for post-tensioned bonded prestressed tensioning grooves, which solves technical problems such as the setting of post-tensioning bars, the setting of tensioning ends, and the setting of reinforcement at the tensioning ends of prestressed beams in densely reinforced areas near the beam ends.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] An optimized structure for post-tensioning with bonded prestressing tension groove includes a prestressed beam, a tensioning side beam disposed at one end of the prestressed beam, and post-tensioning tendons disposed inside the prestressed beam and the tensioning side beam.

[0006] The tensioning side beam includes a tensioning side main beam that is longitudinally connected to the prestressed beam, a tensioning side beam platform set at the tensioning end of the tensioning side main beam, and a tensioning side trough beam set at the tensioning end;

[0007] The post-tensioning bar is anchored at the free end on one side of the prestressed beam, and then passes through the inside of the prestressed beam and the tensioning side main beam, and emerges from the tensioning side beam platform. The post-tensioning bar is U-shaped as a whole and is arranged in an upward arc shape on the tensioning side beam. The post-tensioning bar passes through the corrugated pipe embedded in the prestressed beam and the tensioning side beam.

[0008] The tensioning side beam platform is set in a right-angled triangle protruding along the length of the tensioning side main beam, and its cross-section is rectangular;

[0009] The tensioning side beam platform and the tensioning side channel beam form an L-shaped tensioning end.

[0010] Furthermore, the prestressed beam is a simply supported beam with columns at both ends; one side of the prestressed beam is a free end, and the other side is connected to the tensioning side beam; the free end is set as the anchorage end of the post-tensioning reinforcement.

[0011] Furthermore, the height of the tensioning side main beam is less than that of the prestressed beam, and the top surface of the tensioning side main beam is flush with the top surface of the prestressed beam; the length of the tensioning side main beam is greater than the design length of the dense stirrup area.

[0012] Furthermore, the reinforced stirrups are installed on the tensioning side beam platform and the adjacent tensioning side main beam, and the longitudinal section of the reinforced stirrups is trapezoidal.

[0013] Furthermore, the reinforced stirrups include rectangular main beam edge stirrups, main beam inner stirrups connected inside the main beam edge stirrups, additional stirrup bars connected to the top of the main beam edge stirrups, and additional reinforcing bars connected inside the additional stirrup bars.

[0014] Furthermore, the additional stirrups are vertical extension bars of the main beam edge stirrups and the main beam inner stirrups, and the top of the extension bars are integrally connected by horizontal bars; the additional stirrups are arranged diagonally along the length of the tensioning side beam platform.

[0015] Furthermore, the top of the tensioning side beam platform is also provided with obliquely inserted steel bars at intervals. The obliquely inserted steel bars are inserted obliquely from the top of the tensioning side beam platform into the entire tensioning side beam platform and into the interior of the tensioning side main beam.

[0016] Furthermore, the corrugated pipe includes a side corrugated pipe and a through corrugated pipe. The side corrugated pipe is connected to the prestressed beam and the two side connecting beams perpendicular to the prestressed beam, and the through corrugated pipe is connected to the interior of the prestressed beam and the tensioning side beam.

[0017] Furthermore, the through corrugated pipe is arranged in an arc shape at the tensioning side beam platform and has a corresponding pipe penetration area, which is the area enclosed by the stirrups on the side of the main beam; additional reinforcement bars are provided on both sides of the through corrugated pipe at the penetration area for fixed connection.

[0018] Furthermore, the post-tensioning method includes a construction method for optimized structures with bonded prestressed tensioning grooves. The specific steps are as follows:

[0019] Step 1: Pre-construct the prestressed beams and pre-install corrugated pipes on them; tie the reinforcing bars of the prestressed beams and the reinforcing bars of the tensioned side beams at the same time, and carry out detailed design at the locations where the stirrups are densely packed;

[0020] Step 2: Increase the spacing of the reinforced stirrups to ensure that the corrugated pipe can pass through upwards; and use formwork to mark the location of the pre-reserved tensioning groove when tying the reinforcing bars.

[0021] Step 3: Cast the prestressed beam and tensioned side beam. After the beam concrete is cast and the concrete of the prestressed beam and tensioned side beam meets the design requirements, thread the tensioning bars through the corrugated pipe.

[0022] Step 4: Disconnect the reinforcing bars and stirrups on the side of the beam at the pre-reserved tensioning groove position on the tensioning side beam platform, and insert the tensioning equipment into the tensioning groove through the gap where the reinforcing bars were disconnected to tension the prestressed tendons;

[0023] Step 5: After tensioning is completed, promptly restore the disconnected reinforcing bars and reinforce them with steel bars of the same specification; after the prestressed duct is grouted and anchored, use micro-expansion concrete of a higher grade to seal the prestressed tensioning groove.

[0024] The beneficial effects of this invention are reflected in:

[0025] 1) By setting up a tensioning side beam, this invention extends the tensioning end, which was originally at the end of the prestressed beam, to the tensioning side beam, thus avoiding the dense reinforcement area at the beam end; on the other hand, it provides a tensioning foundation for prestressing tensioning.

[0026] 2) By setting up the tensioning side beam platform and the tensioning side channel beam, the present invention forms a tensioning channel, which realizes convenient tensioning and ensures the tensioning operation space;

[0027] 3) By adding denser stirrups and inclined reinforcing bars, this invention further ensures the reinforcement of the tensioning end, which is beneficial to improving the strength of the beam at the tensioning point;

[0028] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention; the main objects and other advantages of the invention may be realized and obtained by means of the embodiments particularly pointed out in the description. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of an optimized structure for a bonded prestressed tensioning groove in post-tensioning methods.

[0030] Figure 2 This is a partial schematic diagram of an optimized structure for post-tensioned bonded prestressed tensioning grooves;

[0031] Figure 3 This is a detailed design drawing of a post-tensioned bonded prestressed tensioning groove optimized structure.

[0032] Figure 4 This is a schematic diagram of the reinforcement details of the main beam section on the tensioning side;

[0033] Figure 5 This is a schematic diagram of the reinforcement details at the tensioning side beam platform;

[0034] Figure 6 This is a schematic diagram of the overall installation of the corrugated pipe;

[0035] Figure 7 This is a schematic diagram of the corrugated pipe installation at the pipe penetration area.

[0036] Figure reference numerals: 1-Prestressed beam, 2-Post-tensioning reinforcement, 3-Tensioning side beam, 31-Tensioning side main beam, 32-Tensioning side beam platform, 33-Tensioning side channel beam, 4-Column under beam, 5-Dense stirrups, 51-Main beam edge stirrups, 52-Main beam inner stirrups, 53-Additional stirrup reinforcement, 54-Additional reinforcing bars, 6-Inclined steel bars, 7-Corrugated pipe, 71-Through corrugated pipe, 72-Edge corrugated pipe, 8-Pipe penetration area, 9-Additional reinforcement. Detailed Implementation

[0037] Taking a certain energy internet industry project as an example, its beams are prestressed beams. To facilitate the tensioning of post-tensioned steel bars, a post-tensioned bonded prestressed tensioning groove is used to optimize the structure, such as... Figures 1 to 7 As shown, it includes a prestressed beam 1, a tensioning side beam 3 disposed at one end of the prestressed beam 1, and post-tensioning tendons 2 disposed inside the prestressed beam 1 and the tensioning side beam 3; the tensioning side beam 3 includes a tensioning side main beam 31 connected sequentially to the prestressed beam 1, a tensioning side beam platform 32 disposed at the tensioning end of the tensioning side main beam 31, and a tensioning side trough beam 33 disposed at the tensioning end.

[0038] In this embodiment, the post-tensioning bar 2 is anchored at the free end on one side of the prestressed beam 1, and then passes through the interior of the prestressed beam 1 and the tensioning side main beam 31, emerging from the tensioning side beam platform 32. The post-tensioning bar 2 is U-shaped and is arranged in an upward arc shape on the tensioning side beam 3. The post-tensioning bar 2 passes through the corrugated pipe 7 embedded in the prestressed beam 1 and the tensioning side beam 3. The tensioning side beam platform 32 is arranged in a right-angled triangle protruding upward on the tensioning side main beam 31, and its cross-section is rectangular. The tensioning side beam platform 32 and the tensioning side channel beam 33 form an L-shaped tensioning end.

[0039] In this embodiment, the prestressed beam 1 is a simply supported beam with columns 4 at both ends. One side of the prestressed beam 1 is a free end, and the other side is connected to the tensioning beam 3. The free end is used as the anchorage end of the post-tensioning reinforcement 2. The height of the tensioning main beam 31 is less than that of the prestressed beam 1, and the top surface of the tensioning main beam 31 is flush with the top surface of the prestressed beam 1. The length of the tensioning main beam 31 is greater than the design length of the area of ​​the dense stirrups 5.

[0040] In this embodiment, the reinforced stirrups 5 are installed at the tensioning side beam platform 32 and the adjacent tensioning side main beam 31, and the longitudinal section of the reinforced stirrups 5 is trapezoidal. The reinforced stirrups 5 include rectangular main beam edge stirrups 51, main beam inner stirrups 52 connected inside the main beam edge stirrups 51, additional stirrup bars 53 connected to the top of the main beam edge stirrups 51, and additional reinforcing bars 54 connected inside the additional stirrup bars 53. The additional stirrup bars 53 are vertical reinforcement bars that extend the main beam edge stirrups 51 and the main beam inner stirrups 52, and the top of the extension bars are integrally connected by horizontal bars; the additional stirrup bars 53 are arranged diagonally along the longitudinal direction of the tensioning side beam platform 32.

[0041] In this embodiment, the top of the tensioning side beam platform 32 is also provided with obliquely inserted steel bars 6 at intervals. The obliquely inserted steel bars 6 are inserted obliquely from the top of the tensioning side beam platform 32 into the entire tensioning side beam platform 32 and into the interior of the tensioning side main beam 31. The corrugated pipe 7 includes a side corrugated pipe 72 and a through corrugated pipe 71. The side corrugated pipe 72 is connected to the prestressed beam 1 and the two connecting beams perpendicular to the prestressed beam 1 on both sides. The through corrugated pipe 71 is connected to the interior of the prestressed beam 1 and the tensioning side beam 3. The through corrugated pipe 71 is arranged in an arc shape at the tensioning side beam platform 32 and has a corresponding pipe exit area 8. The pipe exit area 8 is the area enclosed by the side stirrups 51 of the main beam. Additional reinforcement bars 9 are provided on both sides of the through corrugated pipe 71 at the exit area for fixed connection.

[0042] Combination Figures 1 to 7 The construction method of the post-tensioned prestressed tensioning groove optimized structure is further explained below, with the specific steps as follows:

[0043] Step 1: Pre-construct prestressed beam 1, and pre-install corrugated pipe 7 on prestressed beam 1; tie the reinforcing bars of prestressed beam 1, and at the same time tie the reinforcing bars of tension side beam 3, among which the design of the 5 densified stirrups is carried out in detail.

[0044] Step 2: Increase the spacing of the reinforced stirrups 5, ensuring that the corrugated pipe 7 extends upwards; and use a template to mark the location of the pre-reserved tensioning groove when tying the reinforcing bars.

[0045] Step 3: Pour the prestressed beam 1 and tension side beam 3. After the beam concrete is poured, and the concrete of the prestressed beam 1 and tension side beam 3 meets the design requirements, thread the post-tensioning bar 2 through the corrugated pipe 7.

[0046] Step 4: Disconnect the reinforcing bars and stirrups 5 on the beam side at the reserved tensioning groove position at the tensioning side beam platform 32, and put the tensioning equipment into the tensioning groove through the gap where the reinforcing bars are disconnected to tension the prestressed tendons.

[0047] Step 5: After tensioning is completed, promptly restore the disconnected reinforcing bars and reinforced stirrups 5, and strengthen them with reinforcing bars of the same specification; after the prestressed duct is grouted and anchored, use micro-expansion concrete of a higher grade to seal the prestressed tensioning groove.

[0048] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. An optimized structure for post-tensioned bonded prestressed tensioning grooves, characterized in that, It includes a prestressed beam (1), a tensioning side beam (3) set at one end of the prestressed beam (1), and post-tensioning bars (2) set inside the prestressed beam (1) and the tensioning side beam (3); The tensioning side beam (3) includes a tensioning side main beam (31) that is connected in sequence with the prestressed beam (1), a tensioning side beam platform (32) set at the tensioning end of the tensioning side main beam (31), and a tensioning side trough beam (33) set at the tensioning end. The post-tensioning bar (2) is anchored at the free end on one side of the prestressed beam (1), and then passes through the interior of the prestressed beam (1) and the tensioning side main beam (31), and emerges from the tensioning side beam platform (32). The post-tensioning bar (2) is U-shaped as a whole and is arranged in an upward arc shape on the tensioning side beam (3). The post-tensioning bar (2) passes through the corrugated pipe (7) embedded in the prestressed beam (1) and the tensioning side beam (3). The tensioning side beam platform (32) is set in a right-angled triangle protruding upwards on the tensioning side main beam (31), and its cross-section is rectangular; The tensioning side beam platform (32) and the tensioning side channel beam (33) form an L-shaped tensioning end.

2. The optimized structure of a post-tensioned bonded prestressed tensioning groove as described in claim 1, characterized in that, The prestressed beam (1) is a simply supported beam with columns (4) at both ends of the beam. One side of the prestressed beam (1) is a free end, and the other side is connected to the tensioning side beam (3). The free end is set as the anchoring end of the post-tensioning reinforcement (2).

3. The optimized structure of a post-tensioned bonded prestressed tensioning groove as described in claim 2, characterized in that, The height of the tensioning side main beam (31) is less than that of the prestressed beam (1), and the top surface of the tensioning side main beam (31) is flush with the top surface of the prestressed beam (1); the length of the tensioning side main beam (31) is greater than the design length of the area of ​​the dense stirrups (5).

4. The optimized structure of a post-tensioned bonded prestressed tensioning groove as described in claim 3, characterized in that, The reinforced stirrups (5) are set at the tensioning side beam platform (32) and the adjacent tensioning side main beam (31), and the longitudinal section of the reinforced stirrups (5) is trapezoidal.

5. The optimized structure of a post-tensioned bonded prestressed tensioning groove as described in claim 4, characterized in that, The reinforced stirrups (5) include a rectangular main beam edge stirrup (51), a main beam inner stirrup (52) connected inside the main beam edge stirrup (51), an additional stirrup (53) connected to the top of the main beam edge stirrup (51), and an additional reinforcing bar (54) connected inside the additional stirrup (53).

6. The optimized structure of a post-tensioned bonded prestressed tensioning groove as described in claim 5, characterized in that, The additional stirrup (53) is a vertical extension bar of the main beam side stirrup (51) and the main beam inner stirrup (52), and the top of the extension bar is integrally connected by a horizontal bar; the additional stirrup (53) is arranged obliquely along the length of the tensioning side beam platform (32).

7. The optimized structure of a post-tensioned bonded prestressed tensioning groove as described in claim 6, characterized in that, The top of the tensioning side beam platform (32) is also provided with obliquely inserted steel bars (6) at intervals. The obliquely inserted steel bars (6) are inserted obliquely from the top of the tensioning side beam platform (32) into the entire tensioning side beam platform (32) and into the interior of the tensioning side main beam (31).

8. The optimized structure of a post-tensioned bonded prestressed tensioning groove as described in claim 7, characterized in that, The corrugated pipe (7) includes a side corrugated pipe (72) and a through corrugated pipe (71). The side corrugated pipe (72) is connected to the prestressed beam (1) and the two side connecting beams perpendicular to the prestressed beam (1). The through corrugated pipe (71) is connected to the interior of the prestressed beam (1) and the tensioning side beam (3).

9. The optimized structure of a post-tensioned bonded prestressed tensioning groove as described in claim 8, characterized in that, The through corrugated pipe (71) is set in an arc shape at the tensioning side beam platform (32) and a corresponding pipe exit area (8) is set. The pipe exit area (8) is the area enclosed by the main beam side stirrups (51). Additional reinforcement (9) is set on both sides of the through corrugated pipe (71) at the exit area for fixed connection.

10. A construction method for an optimized post-tensioned prestressed tensioning groove structure as described in claim 9, characterized in that, The specific steps are as follows: Step 1: Pre-construct the prestressed beam (1), and pre-install the corrugated pipe (7) on the prestressed beam (1); tie the reinforcing bars of the prestressed beam (1), and tie the reinforcing bars of the tension side beam (3) at the same time, and carry out detailed design at the densified stirrups (5); Step 2: For the reinforced stirrups (5), increase the spacing of the stirrups, and the spacing should at least meet the requirement that the corrugated pipe (7) extends upwards; And use formwork to mark the location of the reserved tensioning groove when tying the reinforcing bars; Step 3: Cast the prestressed beam (1) and tension side beam (3). After the beam concrete is cast, and the concrete of the prestressed beam (1) and tension side beam (3) meets the design requirements, the post-tensioning bar (2) is threaded through the corrugated pipe (7). Step 4: Disconnect the reinforcing bars and stirrups (5) on the side of the beam at the pre-reserved tensioning groove position on the tensioning side beam platform (32), and put the tensioning equipment into the tensioning groove from the gap where the reinforcing bars are disconnected to tension the prestressed tendons; Step 5: After tensioning is completed, promptly restore the disconnected reinforcing bars and reinforced stirrups (5), and reinforce them with reinforcing bars of the same specification; after the prestressed duct is grouted and anchored, use micro-expansion concrete of a higher grade to seal the prestressed tensioning groove.

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