Single-pier self-stress bent cap structure

Abstract

The utility model discloses a single-pier self-stress bent cap structure which comprises a single pier and a bent cap poured at the upper end of the single pier. The bent cap is characterized in that the bent cap is composed of a common concrete part at the bottom and a high-expansion concrete part at the upper part, the common concrete part is composed of common concrete and bottom structural ribs poured in the common concrete, and the high-expansion concrete part is composed of high-expansion concrete, an upper row of self-stress ribs, a lower row of self-stress ribs and a self-stress tension plate; the upper row of self-stress ribs and the lower row of self-stress ribs are both poured in the high-expansion concrete, and the upper row of self-stress ribs are connected with the bottom structural ribs through inclined shear-resistant steel bars. According to the single-pier self-stress bent cap structure, the upper row of self-stress ribs in the high-expansion concrete part are connected with the bottom structural ribs through the shear-resistant steel bars, the bent cap is reinforced, and therefore the single-pier self-stress bent cap structure is high in bearing capacity, light in structural size, free of tensioning and grouting, simple in process, low in manufacturing cost, safe, green and environmentally friendly.

Description

Technical Field

[0001] The utility model relates to a single-pier self-stressing capping beam structure, and more specifically, to a single-pier self-stressing capping beam structure without tensioning. Background Art

[0002] With the rapid development of China's economy, the number of motor vehicles is increasing day by day, so urban traffic is becoming busier and busier. To solve traffic congestion, viaducts are springing up. Limited by the limited urban land resource space, in order to minimize the occupied space of viaducts as much as possible, there are more and more single-pier capping beam structures that occupy less land. During the construction of single-pier capping beams, if the single-pier capping beam structure adopts a common reinforced concrete structure, in order to ensure that the strength of the capping beam meets the support requirements, a larger size of the capping beam is required, resulting in a clumsy capping beam structure, which is not conducive to the conservation and beautification of urban space.

[0003] If a prestressed capping beam is adopted, the process is complex and the cost is high. At the same time, there are adverse factors such as slurry pollution during the grouting of the prestressed capping beam. Therefore, there is an urgent need for a new type of capping beam structure to meet the construction of single-pier capping beams for urban traffic. For this reason, the utility model proposes a self-stressing single-pier capping beam structure. Summary of the Invention

[0004] The utility model provides a single-pier self-stressing capping beam structure to overcome the above technical problems.

[0005] The single-pier self-stressing capping beam structure of the utility model includes a single pier and a capping beam cast on the upper end of the single pier; characterized in that: the capping beam is composed of a bottom ordinary concrete part and an upper high-expansion concrete part. The ordinary concrete part is composed of ordinary concrete and bottom structural reinforcement cast therein. The high-expansion concrete part is composed of high-expansion concrete, upper row of self-stressing steel bars, lower row of self-stressing steel bars and self-stressing tensioning plates. The upper row of self-stressing steel bars and the lower row of self-stressing steel bars are both cast in the high-expansion concrete. The self-stressing tensioning plates are arranged at both ends of the high-expansion concrete part. The two ends of the upper row of self-stressing steel bars and the lower row of self-stressing steel bars are respectively fixed on two aligned self-stressing tensioning plates; the upper row of self-stressing steel bars is connected to the bottom structural reinforcement through inclined shear-resistant steel bars.

[0006] In the single-pier self-stressing capping beam structure of the utility model, upper and lower two rows of self-stressing tensioning plates are arranged on both sides of the high-expansion concrete part, and each row of self-stressing tensioning plates is composed of 2 or more self-stressing tensioning plates; two aligned self-stressing tensioning plates at both ends of the high-expansion concrete part are connected through 2 rows or more of upper row of self-stressing steel bars or lower row of self-stressing steel bars.

[0007] For the single-pier self-stressing capping beam structure of the present utility model, the upper end of the shear-resistant steel bar is welded to the upper row of self-stressing steel bars, and the lower end of the shear-resistant steel bar is welded to the bottom structural steel bars; the shear-resistant steel bars are arranged with the upper end facing inwards and the lower end facing outwards, and the angle between the shear-resistant steel bars and the horizontal direction is 45°. The shear-resistant steel bars on the left and right sides in the capping beam are symmetrically distributed.

[0008] For the single-pier self-stressing capping beam structure of the present utility model, both the upper row of self-stressing steel bars and the lower row of self-stressing steel bars adopt BRH400 steel bars with a diameter of 20 mm to 25 mm, and the upper row of self-stressing steel bars and the lower row of self-stressing steel bars are connected to the self-stressing tensioning plate by welding.

[0009] For the single-pier self-stressing capping beam structure of the present utility model, the self-stressing tensioning plate adopts a steel plate with a thickness of 1.5 cm to 2.0 cm.

[0010] For the single-pier self-stressing capping beam structure of the present utility model, both the bottom structural steel bars and the shear-resistant steel bars adopt BRH335 steel bars with a diameter of 20 mm to 25 mm.

[0011] For the single-pier self-stressing capping beam structure of the present utility model, the grades of both the ordinary concrete and the high-expansion concrete are 40 MPa to 50 MPa; 90 days after the high-expansion concrete is poured, the self-stress value generated in the longitudinal direction of the capping beam is 5 MPa to 7 MPa.

[0012] The beneficial effects of the present utility model are as follows: The single-pier self-stressing capping beam structure of the present utility model is composed of a single pier fixed to the foundation and a capping beam fixed to the single pier. The capping beam is composed of an ordinary concrete part at the bottom and a high-expansion concrete part at the upper part, and the upper row of self-stressing steel bars in the high-expansion concrete part is connected to the bottom structural steel bars through shear-resistant steel bars; in this way, when the ordinary concrete is first poured and then the high-expansion concrete is poured, during the solidification and expansion process of the high-expansion concrete, the capping beam generates longitudinal self-stress through the self-stressing tensioning plate and the upper and lower rows of self-stressing steel bars, increasing the bearing capacity of the capping beam in the longitudinal direction. At the same time, by setting the shear-resistant steel bars, the shear resistance of the capping beam in the vertical direction is increased, further strengthening the capping beam, enabling the capping beam to have the ability to bear the upper road structure. The single-pier self-stressing capping beam structure designed in this way has high bearing capacity, the structural size can be made relatively light, there is no need for tensioning and grouting, the process is simple, the cost is low, and it is safe, green and environmentally friendly. Brief Description of the Drawings

[0013] Figure 1 It is a structural schematic diagram of the single-pier self-stressing capping beam structure of the present utility model;

[0014] Figure 2 It is an end view of the capping beam in the present utility model.

[0015] In the figure: 1 upper row of self-stressing bars, 2 lower row of self-stressing bars, 3 self-stressing tensioning plate, 4 high-expansion concrete, 5 bottom structural bars, 6 shear-resistant bars, 7 ordinary concrete, 8 single pier. Detailed implementation mode

[0016] The present utility model will be further described below in conjunction with the accompanying drawings and embodiments.

[0017] As Figure 1 shown, the structural schematic diagram of the single-pier self-stressing capping beam structure of the present utility model is given. Figure 2 The end view of the capping beam in the present utility model is given. The single-pier self-stressing capping beam structure shown in the present utility model is composed of a single pier 8 and a capping beam. The lower end of the single pier 8 is fixed in the foundation, and the capping beam is poured on the upper end of the single pier 8. The capping beam shown is composed of a bottom ordinary concrete part and an upper high-expansion concrete part. The ordinary concrete part is composed of ordinary concrete 7 and bottom structural bars 5 poured therein. The bottom structural bars 5 are the reinforcement of the ordinary concrete part of the capping beam.

[0018] The high-expansion concrete part shown is composed of high-expansion concrete 4, upper row of self-stressing bars 1, lower row of self-stressing bars 2 and self-stressing tensioning plates 3. The upper row of self-stressing bars 1 and the lower row of self-stressing bars 2 are both poured in the high-expansion concrete 4. The self-stressing tensioning plates 3 are arranged at both ends of the high-expansion concrete part, that is, both ends of the capping beam. Both ends of the upper row of self-stressing bars 1 and the lower row of self-stressing bars 2 are respectively fixed on two aligned self-stressing tensioning plates 3, and the connection method is welding.

[0019] In this way, during the solidification process of the poured high-expansion concrete 4, it expands, which will drive the self-stressing tensioning plates 3 to move slightly outwards, and the upper row of self-stressing bars 1 and the lower row of self-stressing bars 2 are restricted by the tension between the two side self-stressing tensioning plates 3, so that compressive self-stress is generated in the longitudinal direction of the high-expansion concrete. The capping beam with self-stress in the longitudinal direction has stronger bearing capacity to support the road structure on the capping beam.

[0020] The upper row of self-stressing bars 1 shown is connected to the bottom structural bars 5 through shear-resistant bars 6. The upper end of the shear-resistant bars 6 is welded to the upper row of self-stressing bars 1, and the lower end of the shear-resistant bars 6 is welded to the bottom structural bars 5. The shear-resistant bars 6 are arranged with the upper end facing inwards and the lower end facing outwards, and the included angle between the shear-resistant bars and the horizontal direction is 45°. The shear-resistant bars on the left and right sides in the capping beam are symmetrically distributed. It can be seen that the upper section of the shear-resistant bars 6 is poured in the high-expansion concrete 4, and the lower section is poured in the ordinary concrete 7. Since the shear-resistant bars 6 are provided in the capping beam, the capping beam has better bearing capacity for vertical shear force, further increasing the firmness of the capping beam.

[0021] It can be seen that due to the compressive stress generated in the longitudinal direction by the high-expansion concrete part of the capping beam, and the shear-resistant steel bars 6 increasing the shear resistance of the capping beam, the single-pier self-stressing capping beam structure designed in this way has high bearing capacity, the structural size can be made relatively light, there is no need for tensioning and grouting, the process is simple, and the cost is low.

[0022] The self-stressing tensioning plates 3 shown are arranged in two upper and lower rows on both sides of the high-expansion concrete part, and the self-stressing tensioning plates 3 on both sides are arranged in alignment. Each row of self-stressing tensioning plates is composed of 2 or more self-stressing tensioning plates 3. The two aligned self-stressing tensioning plates are connected by 2 or more rows of upper-row self-stressing steel bars 1 or lower-row self-stressing steel bars 2.

[0023] Among them, both the upper-row self-stressing steel bars 1 and the lower-row self-stressing steel bars 2 are made of BRH400 steel bars with a diameter of 20mm - 25mm. The upper-row self-stressing steel bars 1 and the lower-row self-stressing steel bars 2 are connected to the self-stressing tensioning plates 3 by welding. The self-stressing tensioning plates 3 are made of steel plates with a thickness of 1.5cm - 2.0cm. Both the bottom structural steel bars 5 and the shear-resistant steel bars 6 are made of BRH335 steel bars with a diameter of 20mm - 25mm. The grades of both the ordinary concrete 7 and the high-expansion concrete 4 are 40MPa - 50MPa; 90 days after the high-expansion concrete is poured, the self-stress value generated in the longitudinal direction of the capping beam is 5MPa - 7MPa.

[0024] During the construction of the single-pier self-stressing capping beam structure of the present utility model, first pour the ordinary concrete 7, and cure the poured ordinary concrete 7 for 3 days after pouring, and then pour the high-expansion concrete 4, and the high-expansion concrete 4 needs to be cured with water for 7 days.

Claims

1. A single-pier self-stressing capping beam structure, comprising a single pier (8) and a capping beam cast on the upper end of the single pier; characterized in that: The capping beam is composed of a general concrete part at the bottom and a high-expansion concrete part at the top. The general concrete part is composed of general concrete (7) and bottom structural reinforcement bars (5) cast therein. The high-expansion concrete part is composed of high-expansion concrete (4), upper row of prestressing tendons (1), lower row of prestressing tendons (2) and prestressing tensioning plates (3). The upper row of prestressing tendons and the lower row of prestressing tendons are both cast in the high-expansion concrete. The prestressing tensioning plates are arranged at both ends of the high-expansion concrete part. The two ends of the upper row of prestressing tendons and the lower row of prestressing tendons are respectively fixed on two aligned prestressing tensioning plates; the upper row of prestressing tendons is connected to the bottom structural reinforcement bars (5) through inclined shear-resistant reinforcement bars (6).

2. The single-pier self-stressing bent cap structure according to claim 1, wherein: There are two upper and lower rows of prestressing tensioning plates (3) arranged on both sides of the high-expansion concrete part. Each row of prestressing tensioning plates is composed of 2 or more prestressing tensioning plates; the two aligned prestressing tensioning plates at both ends of the high-expansion concrete part are connected through 2 rows or more of upper row of prestressing tendons (1) or lower row of prestressing tendons (2).

3. The single-pier self-stressing bent cap structure according to claim 1 or 2, characterized in that: The upper end of the shear-resistant reinforcement bar (6) is welded to the upper row of prestressing tendons (1), and the lower end of the shear-resistant reinforcement bar is welded to the bottom structural reinforcement bars (5); the shear-resistant reinforcement bars are arranged with the upper end facing inwards and the lower end facing outwards, and the included angle between the shear-resistant reinforcement bars and the horizontal direction is 45°. The shear-resistant reinforcement bars on the left and right sides in the capping beam are symmetrically distributed.

4. The single-pier self-stressing capping beam structure according to claim 1 or 2, characterized in that: Both the upper row of prestressing tendons (1) and the lower row of prestressing tendons (2) adopt BRH400 steel bars with a diameter of 20mm - 25mm. The upper row of prestressing tendons and the lower row of prestressing tendons are connected to the prestressing tensioning plates (3) by welding.

5. The single-pier self-stressing bent cap structure according to claim 1 or 2, characterized in that: The prestressing tensioning plates (3) adopt steel plates with a thickness of 1.5cm - 2.0cm.

6. The single-pier self-stressing bent cap structure according to claim 1 or 2, characterized in that: Both the bottom structural reinforcement bars (5) and the shear-resistant reinforcement bars (6) adopt BRH335 steel bars with a diameter of 20mm - 25mm.

7. The single-pier self-stressing bent cap structure according to claim 1 or 2, characterized in that: The grades of both the general concrete (7) and the high-expansion concrete (4) are 40MPa - 50MPa; 90 days after the high-expansion concrete is cast, the self-stress value generated in the longitudinal direction of the capping beam is 5MPa - 7MPa.

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