Continuous box girder side span cast-in-place and closure section few-support overall supporting construction structure and method

Abstract

The invention provides a continuous box girder side span cast-in-place and closure section few-support overall supporting construction structure and method.The continuous box girder side span cast-in-place and closure section few-support overall supporting construction structure comprises a steel pipe support arranged on a transition pier bearing platform, and the top of the steel pipe support is provided with a shakeout unloading cylinder and a profile steel cross beam; the section steel cross beam is connected with the upper portion of the cantilever casting section hanging basket front cross beam through I-shaped steel to form an integral support. An existing hanging basket front cross beam is used as a force bearing point, a foundation does not need to be additionally processed, a few single-row steel pipe columns are arranged on a bearing platform, a support system of a side span cast-in-place section can be formed, meanwhile, the side span cast-in-place section and a side span closure section can share a support for supporting, a side span closure section hanging bracket does not need to be independently designed, and the side span cast-in-place section and a final suspended pouring section can be synchronously constructed; the two-side wing plate full framing constructed in advance can shorten the follow-up side span closure section construction time. The problems of large foundation treatment and material investment of a conventional support method are solved, the contradiction of the construction sequence of a suspension casting section and a side span cast-in-place section of a hanging bracket method is solved, and the method is suitable for side span cast-in-place and closure construction of continuous box girders of highways and railways.

Description

Technical Field

[0001] The invention relates to the technical field of cast-in-place supports for side spans of continuous box girders, and mainly to a cast-in-place support structure and method for integrally supporting a joint section of a continuous box girder with few supports. Background Art

[0002] The cast-in-place of the side span of a continuous beam generally adopts the support method or the hanger method. The support is generally a full-frame support or a multi-row steel pipe support for construction. This method has strong applicability. Since it can be constructed simultaneously with the cantilever casting section, it does not affect the overall construction period, so it is widely used in the cast-in-place of the side span of a continuous beam. However, the investment is relatively high, and the support foundation needs to be processed, the economy is poor, and the time required to set up the support is long. This problem is more prominent in areas with steeper slopes and softer foundations, and the required material investment will increase sharply. In the conventional hanger method, the hanger construction can only be carried out after the cantilever section before the side span joint section is cast and tensioned, and then the side span joint section is constructed. Compared with the full-frame or multi-row steel pipe support method, the cast-in-place section of the side span needs to be carried out after the cantilever casting section is completed, and it cannot be constructed synchronously with the cantilever casting section, which delays the construction time. Summary of the invention

[0003] In order to solve the above technical problems, the present invention provides a continuous box girder side span cast-in-place and joint section with few supports for overall support construction structure and method. The method adopts common materials and has a simple structural form. The existing front crossbeam of the hanging basket is used as the load-bearing point, and no additional treatment is required for the foundation. A small number of single-row steel pipe columns are arranged on the pedestal to form a support system for the side span cast-in-place section. At the same time, the support can be shared with the side span joint section, and there is no need to design a separate hanger for the side span joint section. It can be constructed synchronously with the last suspended casting section. The full-span supports of the two side wing plates constructed in advance can shorten the construction time of the subsequent side span joint section. At the same time, since the casting time of the side span cast-in-place section, the last suspended casting section and the side span joint section is quite close, the overall performance of the continuous beam is more excellent.

[0004] In order to realize the above-mentioned technical features, the purpose of the present invention is achieved as follows: a continuous box girder side span cast-in-place and joint section with few supports as an integral support construction structure, including steel pipe columns arranged on the top of the embedded steel plates of the transition pier cap, sand cylinders are placed on the top of the steel pipe columns, double-piece steel beams are placed on the top of the sand cylinders, the double-piece steel beams are connected to the front beams of the hanging basket with I-beams, and the upper wing plates of the I-beams are equipped with full-span supports and bottom formwork structures.

[0005] Preferably, the steel pipe columns adopt a single-row arrangement structure, and oblique reinforcement rods are fixed between adjacent steel pipe piles.

[0006] Preferably, the steel pipe pile is connected to the transition pier at the top of the pier cap by a channel steel parallel connection.

[0007] Preferably, one end of the I-beam longitudinal beam is in close contact with the transition pier cap beam and supported on the top of the double-piece steel cross beam, and the other end supports and extends over the front cross beam of the hanging basket, and the transition pier cap beam is arranged at the top of the transition pier.

[0008] Preferably, the top of the basket front cross beam is supported by a basket longitudinal beam, the basket longitudinal beam is arranged at intervals from the I-beam longitudinal beam, and the basket front cross beam transfers the load to the diamond basket rear anchor system through the basket front sling; the top of the basket longitudinal beam is supported by a basket bottom mold.

[0009] Preferably, the top of the full-span support is used for the simultaneous casting construction of the top side span cast-in-place section and the side span joint section.

[0010] Preferably, the steel pipe column is constructed in advance; after the construction of the penultimate suspended casting section is completed, the diamond hanging basket is moved forward into position, and after the construction of the last suspended casting section, the I-beam longitudinal beam is erected.

[0011] Preferably, after the overall support is formed by combining the steel pipe column and the lower support of the diamond-shaped hanging basket, the cast-in-place section of the side span and the last suspended section are constructed simultaneously, and finally the side span joint section is constructed. Among them, the last suspended section needs to be tensioned, and the cast-in-place section of the side span can be completed before tensioning.

[0012] Preferably, the I-beam longitudinal beam and the hanging basket longitudinal beam should use the same specifications. If the vertical displacement changes greatly after the casting of the last suspended segment, an I-beam with a smaller specification than the hanging basket longitudinal beam should be used for erection, leaving enough space above the front cross beam of the hanging basket to meet the changing requirements of the vertical displacement of the box girder casting and tensioning.

[0013] Preferably, the bottom formwork structure of the side span cast-in-place section and the side span joint section is smoothly connected with the hanging basket bottom formwork of the last section of the suspended casting section.

[0014] A method for integrally supporting the cast-in-place side span and the closure section of a continuous box girder with few supports, the method being implemented by using the support construction structure, comprising the following steps: Step 1: erect a single row of steel pipe columns on the transition pier cap, connect the steel pipe columns through oblique reinforcement rods, and connect them to the pre-buried steel plates of the transition pier through channel steel flat joints; Step 2: Place the sand cylinder and double-jointed steel beam on the steel pipe column, and the steel pipe column side is ready; Step 3: The penultimate suspended casting section is completed, and the diamond hanging basket is moved forward to prepare for the construction of the last suspended casting section; Step 4: Place an I-beam longitudinal beam on the double-jointed steel beam and the front beam of the hanging basket, with one end of the I-beam longitudinal beam closely attached to the transition pier cap beam and the other end extending over the front beam of the hanging basket; Step 5: erect full-height brackets and bottom formwork structures for the cast-in-place section of the side span and the wing panels of the closure section of the side span on the I-beam longitudinal beam; Step 6: Simultaneously construct the last suspended cast-in-place section and the side span cast-in-place section; Step 7: construct the side span closure section; Step eight, dismantle the full-span support, diamond-shaped hanging basket, steel pipe columns and ancillary structures, and the construction of the side span of the continuous box girder is completed.

[0015] The present invention has the following beneficial effects: 1. The present invention improves and innovates the traditional construction process, is easy to construct, has clear and easy-to-understand process procedures, is highly operable, requires less material input, and is easy to erect and dismantle.

[0016] 2. The present invention considers the supporting structure of the side span cast-in-place, joint closure and a suspended cast section in a unified manner. This structure is simple and the unified construction shortens the construction time, which is conducive to saving construction period.

[0017] 3. The present invention only uses a single row of steel pipe columns to be arranged on the transition pier cap, which is not affected by topographical and geological conditions, does not require foundation reinforcement, and simplifies the process.

[0018] 4. The present invention takes advantage of the characteristics of the I-beam and the bottom formwork of the hanging basket to better fit the bottom line of the box girder based on the characteristics that the bottom of the side span cast-in-place and the joint section is a straight line and the last suspended cast section is a gentle curve. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0020] Figure 1 It is a schematic side view of the arrangement of the integral support of the present invention.

[0021] Figure 2 For the present invention Figure 1 A partial enlarged view of the location of the middle support connection mechanism.

[0022] Figure 3 It is a front schematic diagram of the steel pipe support side of the present invention.

[0023] Figure 4 It is a front side schematic diagram of the front cross beam of the hanging basket of the present invention.

[0024] In the figure: transition pier cap 1, transition pier 2, steel pipe column 3, channel steel flat joint 4, transition pier cap beam 5, sand tube 6, double-piece steel crossbeam 7, I-beam longitudinal beam 8, bottom formwork structure 9, side span cast-in-place section 10, side span joint section 11, last section cantilevered section 12, second to last cantilevered section 13, hanging basket front crossbeam 14, hanging basket longitudinal beam 15, hanging basket bottom formwork 16, hanging basket front sling 17, diamond hanging basket 18, oblique reinforcement rod 19, full-span bracket 20. DETAILED DESCRIPTION

[0025] The embodiments of the present invention are further described below in conjunction with the accompanying drawings.

[0026] Embodiment 1: See also Figure 1-4 A construction structure for the cast-in-place and joint section of a continuous box girder with few supports as a whole, including a steel pipe column 3 arranged at the top of the embedded steel plate of the transition pier cap 1, a sand tube 6 is placed at the top of the steel pipe column 3, a double-jointed steel beam 7 is placed at the top of the sand tube 6, the double-jointed steel beam 7 is connected to the front crossbeam 14 of the hanging basket by an I-beam longitudinal beam 8, and the upper wing plate of the I-beam longitudinal beam 8 is equipped with a full-span support 20 and a bottom formwork structure 9. The above-mentioned construction structure, whose constituent materials are common and the structural form is simple, is composed of a steel pipe support and a front crossbeam of the hanging basket, which speeds up the support installation and box girder casting speed, ensures the safety of the cast-in-place and joint section construction of the continuous beam side span, and is suitable for the cast-in-place and joint section construction of the continuous box girder side span under various circumstances.

[0027] Furthermore, the steel pipe columns 3 are arranged in a single row, and oblique reinforcing rods 19 are fixed between adjacent steel pipe piles 3. By adopting the oblique reinforcing rods 19, the strength and stability of the connection structure of adjacent steel pipe columns 3 can be enhanced, thereby ensuring the safety of the support during the construction process.

[0028] Furthermore, the steel pipe pile 3 is connected to the transition pier 2 at the top of the pier cap 1 by a channel steel flat joint 4. The channel steel flat joint 4 can realize a reliable fixed connection between the steel pipe pile 3 and the transition pier 2, thereby enhancing the structural stability of the steel pipe pile 3.

[0029] Furthermore, one end of the I-beam longitudinal beam 8 is in close contact with the transition pier cap beam 5 and supported on the top of the double-piece steel cross beam 7, and the other end supports and extends through the front cross beam 14 of the hanging basket. The transition pier cap beam 5 is arranged at the top of the transition pier 2. The fixed installation structure of the I-beam longitudinal beam 8 is used to ensure the end positioning of the I-beam longitudinal beam 8, and at the same time, its stable support is achieved, ensuring its structural reliability. The front cross beam 14 of the hanging basket can be used to transfer the bearing capacity of the I-beam longitudinal beam 8 to the anchoring system.

[0030] Furthermore, the top of the basket front cross beam 14 supports a basket longitudinal beam 15, which is arranged at intervals with the I-beam longitudinal beam 8. The basket front cross beam 14 transfers the load to the rear anchor system of the diamond basket 18 through the basket front sling 17; the top of the basket longitudinal beam 15 supports a basket bottom formwork 16. The basket longitudinal beam 15 can reliably support the basket bottom formwork 16, and effectively transfer the bearing capacity to the anchoring system during the pouring process.

[0031] Furthermore, the top of the full-span bracket 20 is used for the synchronous pouring construction of the top side span cast-in-place section 10 and the side span joint section 11. The full-span bracket 20 can be used for the pouring construction support during the subsequent pouring process of the side span cast-in-place section 10 and the side span joint section 11.

[0032] Further, the steel pipe column 3 is constructed in advance; after the penultimate suspended casting section 13 is completed, the diamond hanging basket 18 is moved forward to its position, and after the last suspended casting section 12 is constructed, the I-beam longitudinal beam 8 is set up. Through the above-mentioned pouring construction sequence, the safety of the entire pouring construction is guaranteed.

[0033] Furthermore, after the steel pipe column 3 and the diamond hanging basket 18 are combined to form an overall support, the side span cast-in-place section 10 and the last section suspended cast-in-place section 12 are constructed synchronously first, and the side span joint section 11 is constructed last. Among them, the last section suspended cast-in-place section 12 needs to be tensioned, and the side span cast-in-place section 10 can be completed before tensioning. Since the last section suspended cast-in-place section 12 needs to be tensioned, the side span cast-in-place section 10 can be completed before tensioning without affecting the overall construction period.

[0034] Furthermore, conventional I-beam longitudinal beams 8 and hanging basket longitudinal beams 15 should use the same specifications. If the vertical displacement changes greatly after the casting of the last suspended segment 12, I-beams with smaller specifications than the hanging basket longitudinal beams 15 can be used for erection, leaving enough space above the front cross beam 14 of the hanging basket to meet the changing requirements of the vertical displacement of the box girder casting and tensioning.

[0035] Furthermore, the bottom formwork structure 9 of the side span cast-in-place section 10 and the side span joint section 11 should be connected smoothly with the hanging basket bottom formwork 16 of the last section of the suspended casting section 12.

[0036] Embodiment 2: A method for integrally supporting the cast-in-place side span and the closure section of a continuous box girder with few supports, the method being implemented by using the support construction structure, comprising the following steps: Step 1: a single row of steel pipe columns 3 are set up on the transition pier cap 1, the steel pipe columns 3 are connected by oblique reinforcing rods 19, and are connected to the pre-buried steel plates of the transition pier 2 through channel steel flat joints 4; Step 2: Place the sand tube 6 and the double-jointed steel beam 7 on the steel pipe column 3, and the steel pipe column side is ready; Step 3: The penultimate suspended casting section 13 is completed, and the diamond hanging basket 18 is moved forward to prepare for the construction of the last suspended casting section 12; Step 4: Place an I-beam longitudinal beam 8 above the double-jointed steel beam 7 and the front beam 14 of the hanging basket, with one end of the I-beam longitudinal beam 8 in close contact with the transition pier cap beam 5 and one end extending through the front beam 14 of the hanging basket; Step 5: erecting the side span cast-in-place section 10 and the side span joint section 11 on the I-beam longitudinal beam 8 to use the full-height bracket 20 and the bottom formwork structure 9 for the wing plate; Step 6: synchronously construct the last suspended cast-in-place section 12 and the side span cast-in-place section 10; Step seven, constructing the side span closure section 11; Step eight, dismantle the full-span support 20, diamond-shaped hanging basket 18, steel pipe column 3 and auxiliary structures, and the construction of the side span of the continuous box girder is completed.

Claims

1. A continuous box girder side span cast-in-place and joint section with few supports for integral support construction, characterized in that: The invention comprises a steel pipe column (3) arranged at the top of the embedded steel plate of the transition pier cap (1), a sand cylinder (6) is placed at the top of the steel pipe column (3), a double-jointed steel beam (7) is placed at the top of the sand cylinder (6), the double-jointed steel beam (7) is connected to the front beam (14) of the hanging basket by an I-beam longitudinal beam (8), and a full-height bracket (20) and a bottom mold structure (9) are arranged on the upper wing plate of the I-beam longitudinal beam (8).

2. According to claim 1, a continuous box girder side span cast-in-place and joint section with few supports for integral support construction structure, characterized in that: The steel pipe columns (3) adopt a single-row arrangement structure, and oblique reinforcement rods (19) are fixed between adjacent steel pipe piles (3).

3. According to claim 1, a continuous box girder side span cast-in-place and joint section with few supports for integral support construction structure, characterized in that: The steel pipe pile (3) is connected to the transition pier (2) at the top of the pier cap (1) via a channel steel flat joint (4).

4. According to claim 3, a continuous box girder side span cast-in-place and joint section with few supports for integral support construction structure, characterized in that: One end of the I-beam longitudinal beam (8) is in close contact with the transition pier cap beam (5) and is supported on the top of the double-jointed steel cross beam (7), and the other end supports and extends over the front cross beam (14) of the hanging basket. The transition pier cap beam (5) is arranged on the top of the transition pier (2).

5. According to claim 1, a continuous box girder side span cast-in-place and joint section with few supports for integral support construction structure, characterized in that: The top of the basket front cross beam (14) is supported by a basket longitudinal beam (15), the basket longitudinal beam (15) and the I-beam longitudinal beam (8) are arranged at intervals, and the basket front cross beam (14) transfers the load to the rear anchor system of the diamond basket (18) through the basket front sling (17); the top of the basket longitudinal beam (15) is supported by a basket bottom mold (16).

6. According to claim 5, a continuous box girder side span cast-in-place and joint section with few supports for integral support construction structure, characterized in that: The top of the full span support (20) is used for the synchronous casting construction of the top side span cast-in-place section (10) and the side span joint section (11).

7. According to claim 6, a continuous box girder side span cast-in-place and joint section with few supports for integral support construction structure, characterized in that: The steel pipe column (3) is constructed in advance; after the construction of the penultimate suspended casting section (13) is completed, the diamond hanging basket (18) is moved forward to its position, and after the construction of the last suspended casting section (12), the I-beam longitudinal beam (8) is erected.

8. According to claim 7, a continuous box girder side span cast-in-place and joint section with few supports for integral support construction structure, characterized in that: After the steel pipe column (3) and the lower support of the diamond hanging basket (18) are combined to form an overall support, the side span cast-in-place section (10) and the last section suspended cast-in-place section (12) are first constructed synchronously, and finally the side span joint section (11) is constructed. Among them, the last section suspended cast-in-place section (12) needs to be tensioned, and the side span cast-in-place section (10) can be completed before tensioning.

9. According to claim 7, a continuous box girder side span cast-in-place and joint section with few supports for integral support construction structure, characterized in that: The I-beam longitudinal beam (8) and the basket longitudinal beam (15) should be of the same specifications. If the vertical displacement changes greatly after the last suspended cast segment (12) is cast, an I-beam with a smaller specification than the basket longitudinal beam (15) should be used for erection, leaving enough space above the front cross beam (14) of the basket to meet the requirements of the change of vertical displacement during the casting and tensioning of the box beam; The bottom formwork structure (9) of the side span cast-in-place section (10) and the side span joint section (11) is connected in sequence with the hanging basket bottom formwork (16) of the last suspended cast section (12).

10. A method for constructing continuous box girder side span cast-in-place and joint section with few supports for integral support, characterized in that: The construction method is implemented by using the supporting construction structure according to any one of claims 1 to 9, and comprises the following steps: Step 1: erecting a single row of steel pipe columns (3) on the transition pier cap (1), connecting the steel pipe columns (3) by oblique reinforcing rods (19), and connecting them to the embedded steel plates of the transition pier (2) by channel steel parallel joints (4); Step 2: Place the sand cylinder (6) and the double-jointed steel beam (7) on the steel pipe column (3), and the steel pipe column side is ready; Step 3: The penultimate suspended casting section (13) is completed, and the diamond hanging basket (18) is moved forward to prepare for the construction of the last suspended casting section (12); Step 4: placing an I-beam longitudinal beam (8) above the double-jointed steel beam (7) and the front beam (14) of the hanging basket, wherein one end of the I-beam longitudinal beam (8) is in close contact with the transition pier cap beam (5) and the other end extends over the front beam (14) of the hanging basket; Step 5, erecting a full-height bracket (20) and a bottom formwork structure (9) for the wing panels of the side span cast-in-place section (10) and the side span joint section (11) on the I-beam longitudinal beam (8); Step 6: synchronously construct the last suspended cast-in-place section (12) and the side span cast-in-place section (10); Step 7, constructing the side span closure section (11); Step 8: dismantle the full-height bracket (20), diamond-shaped hanging basket (18), steel pipe column (3) and auxiliary structure, and the construction of the side span of the continuous box girder is completed.

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