A novel closure process for the triangular section of a hollow rigid frame bridge

Abstract

This invention relates to a novel closure process for the triangular section of a hollow rigid frame bridge. After construction reaches the lower chord X10# block and the upper chord S9# block, the lower chord hanging basket bottom formwork system is temporarily anchored to the bottom plate of the beam segment of the lower chord X10# block, and the lower chord triangular hanging basket is removed. A temporary locking device of upper and lower chord tubular columns is installed between the upper chord S9# block and the lower chord X9# block. A steel pipe support with fasteners for the bottom and web plates of the upper chord S10# block is installed on the top plate of the beam segment of the lower chord X10# block, and the upper chord S10# block is constructed. After reassembly, the upper chord hanging basket of the solid web area is assembled, and the closure block 11# is constructed in two horizontal layers, with the horizontal layer section being the top of the lower chord box girder. This invention constructs the closure block in two horizontal layers, adapting to the structural characteristics of the triangular section of a hollow rigid frame bridge and the requirements of asynchronous construction technology for the upper and lower chords. It eliminates the need for a large number of full-span scaffolds, simplifies the process, improves the utilization rate of the hanging basket, achieves rapid closure of the triangular section, and effectively shortens the construction cycle.

Description

Technical Field

[0001] This invention relates to the field of bridge construction technology, specifically to a novel closure process for the triangular section of a hollow rigid frame bridge. Background Technology

[0002] Long-span concrete hollow rigid frame bridges are widely used in bridge projects spanning rivers and valleys due to their strong spanning capacity, high structural rigidity, and beautiful appearance. Their triangular area is a key stress-bearing part where the upper and lower chords intersect, and the efficiency and quality of the closure construction directly determine the stability and safety of the overall bridge structure.

[0003] The existing construction technology for closure of the triangular section of a hollow rigid frame bridge is affected by factors such as the complexity of the triangular section structure, dense reinforcement, and limited space for operation. The closure block is cast in one piece, which leads to problems such as insufficient concrete vibration and difficulty in controlling the casting quality. Moreover, the integral casting requires the erection of a large number of scaffolds, the construction process is cumbersome, and the utilization efficiency of equipment such as hanging baskets is low, resulting in a long construction period and high construction costs. At the same time, the asynchronous construction of the upper and lower chord structures in the triangular section makes it difficult to control the deformation and posture of the closure joint. The integral casting is prone to cracks due to structural deformation, which affects the durability of the bridge structure.

[0004] Therefore, it is urgent to develop a closure process that is adapted to the structural characteristics of the triangular area of ​​a hollow rigid frame bridge, so as to achieve both rapid closure and construction quality assurance. Summary of the Invention

[0005] The purpose of this invention is to provide a novel closure process for the triangular section of a hollow rigid frame bridge, in order to solve the technical problems of poor quality control, low construction efficiency, and difficulty in posture control in existing triangular section closure processes.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A novel closure process for the triangular section of a hollow rigid frame bridge is provided, the closure process comprising:

[0008] The lower chord of the hollow rigid frame bridge was constructed using a triangular hanging basket on the lower chord until the lower chord X10# block was completed.

[0009] The upper chord of the hollow rigid frame bridge was constructed using a diamond-shaped hanging basket until the upper chord S9# block was completed.

[0010] The lower chord hanging basket bottom formwork system is temporarily anchored to the bottom plate of the beam segment of the lower chord X10# block, and then the lower chord triangular hanging basket is removed;

[0011] Move the upper chord diamond hanging basket to the position of the upper chord S10# block, remove the bottom formwork system of the upper chord hanging basket, and install the upper and lower chord tube column temporary locking device between the upper chord S9# block and the lower chord X9# block to complete the temporary locking of the upper and lower chords in the triangular area.

[0012] Install the bottom and web fastener-type steel pipe support for the upper chord S10# block on the top plate of the beam segment of the lower chord X10# block, and construct the upper chord S10# block;

[0013] The lower chord hanging basket bottom mold system and the upper chord diamond hanging basket above are connected to each other by the hanging rods to form the recombined solid area upper chord hanging basket, which is then moved to the position of the closure block 11#.

[0014] The closure block #11 was constructed in two horizontal layers, with the horizontal layer section being the top of the lower chord box girder.

[0015] Furthermore, the upper and lower chord column type temporary locking device includes a vertical column and an inclined tube body intersecting between adjacent vertical columns;

[0016] The upper and lower ends of the vertical column are respectively fixed to the bottom plate of the upper chord S9# block and the top plate of the lower chord X9# block.

[0017] Furthermore, the upper chord S10# block bottom and web plate fastener type steel pipe support includes a lattice frame body composed of uprights and longitudinal and transverse horizontal bars. The upper and lower parts of the lattice frame body are provided with diagonal sweeping bars, and the lattice frame body is provided with X-shaped scissor braces.

[0018] The intersection of the uprights and the longitudinal and transverse horizontal bars is fixed by fasteners;

[0019] The top of the upright is connected to a U-shaped top support, and a pad is provided between the U-shaped top support and the bottom plate of the beam segment of the upper chord S10# block.

[0020] Furthermore, the construction of the upper chord S10# block includes:

[0021] The upper chord diamond-shaped hanging basket provides outer and inner molds, and is used in conjunction with the upper chord S10# block bottom and web plate fastener-type steel pipe support for the construction of the upper chord S10# block;

[0022] During the installation of reinforcing bars, the vertical prestressing tendons along the entire length of the upper and lower chords are laid out in advance. The prestressing ducts are positioned using a grid-shaped steel bar, and the grid-shaped steel bar is spot-welded to the vertical prestressing tendons along the entire length for fixation.

[0023] Furthermore, in the reconstructed solid abdominal region upper chord hanging basket, the outer mold of the upper chord rhomboid hanging basket is extended and connected to the outer mold of the lower chord triangular hanging basket.

[0024] Furthermore, the outer steel plate of the closure block 11# includes the side plate and the outer steel plate of the intersection area of ​​the upper and lower chords. The outer steel plate of the intersection area of ​​the upper and lower chords includes the top plate of the lower chord, the arc plate, and the bottom plate of the upper chord.

[0025] Furthermore, the first phase of construction for the closure block #11 includes:

[0026] Install the side plates of the lower chord box girder section;

[0027] Install the bottom chord top plate and the arc plate in the outer steel plate of the intersection area of ​​the upper and lower chords as the bottom pressure plate;

[0028] The lower chord box girder section was poured using the combined lower chord hanging basket bottom formwork system.

[0029] Furthermore, during the first construction of the closure block 11#, vibration holes were pre-reserved on the top plate of the lower chord in the outer steel plate of the intersection area of ​​the upper and lower chords for concrete vibration.

[0030] Furthermore, the second phase of construction for closure block #11 includes:

[0031] Install the side plates of the upper chord box girder section;

[0032] Install the bottom plate of the upper chord in the outer steel plate of the intersection area of ​​the upper and lower chords;

[0033] Using the concrete surface from the first construction as support, the upper chord box girder section was poured.

[0034] Furthermore, during the second construction of the closure block 11#, a support frame was erected on the top of the lower chord top plate in the outer steel plate of the upper and lower chord intersection area, and the top of the support frame supported the bottom plate of the upper chord in the outer steel plate of the upper and lower chord intersection area.

[0035] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0036] This invention provides a novel closure process for the triangular section of a hollow rigid frame bridge. The closure blocks are constructed using symmetrical layered casting with pre-reserved vibration holes in the inner formwork. The outer steel plates are installed in sections, and the prestressed tendons are pre-laid out to avoid obstruction. This solves the problems of dense reinforcement and insufficient concrete vibration in the triangular section, effectively ensuring the quality of concrete pouring. Simultaneously, the closure blocks are constructed in two horizontal layers, adapting to the structural characteristics of the triangular section of the hollow rigid frame bridge and the asynchronous construction process of the upper and lower chords. The first construction relies on the lower chord formwork, and the second construction relies on the initial concrete surface and the upper chord formwork, eliminating the need for extensive full-span scaffolding, significantly simplifying the construction process, improving the utilization rate of the formwork equipment, achieving rapid closure of the triangular section, and effectively shortening the construction cycle. Furthermore, the construction process of this invention uses a pipe-column structure to temporarily lock the upper and lower chords of the triangular section during low-temperature periods, effectively controlling the posture of the closure joint, ensuring the stability of the bridge structure system in the hollow section, and improving construction quality. Attached Figure Description

[0037] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other embodiments can be obtained from these drawings without creative effort.

[0038] Figure 1 This is a schematic diagram of asynchronous construction of the upper and lower chords of a hollow rigid frame bridge provided in an embodiment of the present invention.

[0039] Figure 2 This is a schematic diagram of the bottom formwork system and side formwork anchoring provided in an embodiment of the present invention.

[0040] Figure 3 This is a schematic diagram of the basket reassembly, temporary locking, and bracket arrangement provided in an embodiment of the present invention.

[0041] Figure 4 This is a schematic diagram of the layered casting of the closure block 11# provided in an embodiment of the present invention.

[0042] Figure 5 This is a schematic diagram of the segmentation and installation of the outer steel plate provided in an embodiment of the present invention.

[0043] Figure 6 This is a structural diagram of the upper chord S10# block bottom and web plate fastener type steel pipe support provided in an embodiment of the present invention.

[0044] The diagram is labeled as follows:

[0045] 1-Lower chord triangular hanging basket, 2-Lower chord X10# block, 3-Upper chord S9# block, 4-Lower chord hanging basket bottom formwork system, 5-Lower chord hanging basket outer formwork, 6-Upper chord diamond hanging basket, 7-Upper chord hanging basket bottom formwork system, 8-Upper chord S10# block, 9-Upper and lower chord pipe column type temporary locking device, 10-Upper chord S10# block bottom and web plate fastener type steel pipe support, 11-Upper chord hanging basket in solid web area after reassembly, 12-Closing block 11# block, 13-Last bundle of temporary fasteners for the lower chord, 14-Horizontal layered casting interface of the closing block, 15-Outer steel plate of web plate intersection section, 16-Outer steel plate of upper and lower chord intersection area, 17-Dividing line of outer steel plate of web plate, 18-Lower chord X9# block;

[0046] 1001-Upright pole, 1002-Longitudinal and transverse horizontal bars, 1003-Sweeping bar, 1004-Scissor brace, 1005-U-shaped top support, 1006-Padded block. Detailed Implementation

[0047] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the invention.

[0048] In the description of this invention, it should be understood that the terms "upper", "lower", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0049] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," "setting," etc., should be interpreted broadly. For example, they can refer to a fixed connection or setting, a detachable connection or setting, or an integral connection or setting. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0050] It should also be noted that although the order of steps is mentioned in the method description, in some cases, steps may be performed in a different order than that described here, and this should not be interpreted as a restriction on the order of steps.

[0051] The triangular section of the hollow rigid frame bridge consists of an upper chord, a lower chord, and piers. The roots of the upper and lower chords are connected by vertical piers, and the connection method is integral concrete casting. The root of the upper chord is the upper chord S0# block, and the root of the lower chord is the lower chord X0# block. Starting from the upper chord S0# block and the lower chord X0# block, the upper and lower chords are constructed symmetrically to both sides.

[0052] This invention provides a novel closure process for the triangular section of a hollow rigid frame bridge, applicable to the construction of long-span railway concrete hollow rigid frame bridges. It solves technical problems such as the confined space, dense reinforcement, difficulty in controlling the closure posture, and susceptibility to cracking during pouring in the triangular section of hollow rigid frame bridges. Based on the structural characteristics of the hollow triangular section and the asynchronous construction requirements of the upper and lower chords, the triangular section is poured independently in two stages along the top surface of the lower chord box girder: the first stage utilizes the lower chord formwork for pouring, using the concrete surface from the first stage as support for the second stage's bottom plate and web of the closure block. Simultaneously, the upper chord formwork serves as support for the top plate and flanges of the closure block. Combined with the formwork dismantling and reassembly, temporary locking, installation of external steel plates, scaffolding erection, and layered symmetrical pouring, the hollow triangular section is rapidly closed with controllable quality and stable alignment. This process offers advantages such as high construction efficiency, strong quality control, and convenient operation.

[0053] Specifically, the closure process includes the following construction steps:

[0054] S1: As Figure 1 The lower chord of the hollow rigid frame bridge is constructed using the lower chord triangular hanging basket 1 until the lower chord X10# block 2 is completed.

[0055] The lower chord triangular hanging basket 1 includes a triangular truss, a bottom formwork platform (i.e., the lower chord hanging basket bottom formwork system 4), inner and outer formwork, a suspension system (including hangers), an anchoring system, and a traveling system, which can use existing conventional equipment.

[0056] S2: As Figure 1 The upper chord of the hollow rigid frame bridge is constructed using the upper chord diamond hanging basket 6 until the upper chord S9# block 3 is completed.

[0057] The upper chord rhomboid hanging basket 6 includes a rhomboid truss, a bottom formwork platform (i.e., the upper chord hanging basket bottom formwork system 7), inner and outer formwork, a suspension system (including hangers), an anchoring system, and a traveling system, which can use existing conventional equipment.

[0058] S3: As Figure 2 The lower chord hanging basket bottom formwork system 4 is temporarily anchored to the bottom plate of the beam segment of lower chord X10# block 2. Then, the triangular truss is removed, the outer formwork is fixed to the beam segment of lower chord X10# block 2, and the remaining parts of the lower chord triangular hanging basket 1 are removed.

[0059] At the same time, the prestressed tendon tensioning and grouting of block S9#3 of the upper chord were completed.

[0060] S4: As Figure 3 Move the upper chord diamond-shaped hanging basket 6 to the position of the upper chord S10# block 8, remove the upper chord hanging basket bottom mold system 7, and install the upper and lower chord tube column temporary locking device 9 between the upper chord S9# block 3 and the lower chord X9# block 17 to complete the temporary locking of the upper and lower chords in the triangular area.

[0061] The temporary locking device 9 for upper and lower chord columns includes vertical columns and inclined tubes intersecting between adjacent vertical columns. The upper and lower ends of the vertical columns are fixed to the bottom plate of the beam segment of the upper chord S9# block 3 and the top plate of the beam segment of the lower chord X9# block 17, respectively. Steel plates are pre-embedded in the bottom plate of the beam segment of the upper chord S9# block 3 and the top plate of the beam segment of the lower chord X9# block 17 for connection and fixation with the vertical columns.

[0062] Temporary locking is carried out when the temperature is low and relatively stable. After the locking requirements are met, wedge-shaped pads are used to pad the top of the vertical column on the inclined surface of the beam bottom. All connection parts are welded on site to complete the locking and ensure the stability of the bridge structure system in the hollow area and the closure position.

[0063] S5: Install the bottom and web fastener type steel pipe support 10 of the upper chord S10# block on the top plate of the beam segment of the lower chord X10# block 2, and construct the upper chord S10# block 8.

[0064] like Figure 6 The upper chord S10# block bottom and web plate fastener-type steel pipe support 10 includes a lattice frame composed of uprights 1001 and longitudinal and transverse horizontal bars 1002. The upper and lower parts of the lattice frame are provided with diagonal sweeping bars 1003, and X-shaped scissor braces 1004 are installed inside the lattice frame. The intersections of the uprights 1001 and the longitudinal and transverse horizontal bars 1002 are fixed by fasteners.

[0065] The top of the upright 1001 is connected to the U-shaped top support 1005, and a pad 1006 is provided between the U-shaped top support 1005 and the bottom plate of the beam segment of the upper chord S10# block 8. The bottom of the upright 1001 is supported to the top plate of the beam segment of the lower chord X9# block 17.

[0066] If necessary, a U-shaped top support 1005 is also connected to the inner end of the horizontal bar. An I-beam is fixed to the side of the vertical column of the temporary locking device 9 of the upper and lower chord column on this side. A pad 1006 is also provided between the U-shaped top support 1005 and the I-beam.

[0067] Construction of upper chord S10# block 8, including:

[0068] S501: The upper chord diamond hanging basket 6 provides the outer mold and inner mold, and together with the upper chord S10# block bottom and web plate fastener-type steel pipe support 10, the upper chord S10# block 8 is constructed.

[0069] S502: When installing the reinforcing bars, the vertical prestressing tendons along the entire length of the upper and lower chords are laid out in advance. The prestressing ducts are positioned using a grid-shaped reinforcing bar, and the grid-shaped reinforcing bars are spot-welded to the vertical prestressing tendons along the entire length.

[0070] S6: Connect the lower chord hanging basket bottom mold system 4 and the upper chord diamond hanging basket 6 above with the hanging rod to form the recombined solid area upper chord hanging basket 11, and move to the position of the closing block 11# block 12.

[0071] In the reconstructed solid abdominal region upper chord hanging basket 11, the outer mold of the upper chord rhomboid hanging basket 6 is extended and connected to the outer mold of the lower chord triangular hanging basket 1.

[0072] When constructing the upper chord S10# block 8, install the outer steel plate 15 of the web intersection section, such as... Figure 6 The main function of the steel plate 15 encasing the web section is to disperse the peak stress in the triangular area, suppress the stress concentration in the closure area that causes concrete cracking, and improve crack resistance.

[0073] S7: As Figure 4After tensioning the last temporary cable of the lower chord, the closure block 11#12 was constructed in two horizontal layers, with the horizontal layer section being the top of the lower chord box girder. The first construction used the lower chord triangular hanging basket 1 to complete the pouring. The second construction used the concrete surface from the first construction as support to construct the second bottom plate and web of the closure block 11#12, while the upper chord rhomboid hanging basket 6 was used as support to construct the top plate and flange of the closure block 11#12, completing the rapid closure of the hollow triangular area.

[0074] like Figure 5 The outer steel plate of the closure block 11# block 12 includes the side plate and the outer steel plate 16 of the intersection area of ​​the upper and lower chords. The side plate on one side is divided into six pieces. The outer steel plate 16 of the intersection area of ​​the upper and lower chords includes the lower chord top plate, the arc plate and the upper chord bottom plate.

[0075] The outer steel plates of closure blocks 11 and 12 were all hoisted using tower cranes with chain hoists for position adjustment, and then connected and fixed to the side formwork with bolts. The side plates were hoisted in six stages, and the outer steel plate 16 at the intersection of the upper and lower chords was hoisted in three stages. Thin steel strips were used for the joints, and the gap width was controlled within 20mm.

[0076] The first construction of closure block 11# and block 12 includes the following steps:

[0077] S701: Install the side plates of the lower chord box girder; then install the bottom web reinforcement and vertical prestressed reinforcement; then install the inner formwork system.

[0078] S702: Install the lower chord top plate and arc plate in the outer steel plate 16 of the upper and lower chord intersection area as the lower pressure plate.

[0079] S703: Combined lower chord hanging basket bottom formwork system 4, for casting the lower chord box girder section.

[0080] During the initial construction of closure block 11# and block 12, vibration holes were pre-reserved on the top plate of the lower chord in the outer steel plate 16 at the intersection of the upper and lower chords for concrete vibration. When the concrete height was close to the required level, the vibration holes were sealed and welded with the same specification outer steel plate. After concrete pouring, water was used for moisture retention and curing, and the interface between segments was roughened.

[0081] The second construction of closure block 11# and block 12 includes the following steps:

[0082] S704: Install the side plates of the upper chord box girder; then add reinforcement bars; then install the inner formwork system.

[0083] S705: Install the bottom plate of the upper chord in the outer steel plate 16 of the intersection area of ​​the upper and lower chords.

[0084] S706: Using the concrete surface from the first construction as support, pour the upper chord box girder section.

[0085] During the second construction of the closure block 11# block 12, a support frame was erected on the top of the lower chord top plate of the outer steel plate 16 in the intersection area of ​​the upper and lower chords. The top of the support frame supported the bottom plate of the upper chord in the outer steel plate 16 in the intersection area of ​​the upper and lower chords.

[0086] The concrete pouring of the closure blocks 11# and 12 was carried out using high-pressure pump pipes, and a tremie pipe was installed to reduce the free fall height of the concrete.

[0087] After the closure construction is completed, the working conditions of key processes are inspected, including the structural inspection after the hanging basket is reassembled, the quality inspection of the temporary locking structure installation, the quality inspection of the outer steel plate installation, the quality inspection of the steel reinforcement formwork installation, and the inspection of the edge protection measures. Only after the inspection is passed can the corresponding process be carried out.

[0088] The closure process of the present invention has the following technical advantages:

[0089] 1. This invention involves two horizontal and layered constructions of the closure block, which is adapted to the structural characteristics of the triangular area of ​​a hollow rigid frame bridge and the asynchronous construction process of the upper and lower chords. The first construction relies on the lower chord hanging basket, and the second construction relies on the first concrete surface and the upper chord hanging basket. This eliminates the need to erect a large number of full-span scaffolds, greatly simplifies the construction process, improves the utilization rate of the hanging basket equipment, achieves rapid closure of the triangular area, and effectively shortens the construction cycle.

[0090] 2. In the process of this invention, the closure block is poured in symmetrical layers, and the inner mold is reserved with vibration holes, which solves the problem of dense reinforcement and insufficient concrete vibration in the triangular area; at the same time, the outer steel plate is installed in sections and the prestressed tendons are laid out in advance to avoid them, which effectively improves the installation accuracy of the reinforcement, formwork and steel plate, ensures the quality of concrete pouring and avoids the generation of structural cracks.

[0091] 3. In the process of this invention, during the low-temperature period, a pipe column structure is used to temporarily lock the upper and lower chords of the triangular area, effectively controlling the closure posture and ensuring the stability of the bridge structure system in the hollow area; during the reorganization of the hanging basket, the bottom formwork and guide beam are hoisted and converted, the side formwork is extended with the truss, and connected with the lower chord side formwork to form the hanging basket in the solid area; in conjunction with the erection of the fastener-type steel pipe support, a stable support system is provided for the closure construction, reducing the risk of high-altitude operations.

[0092] 4. In the process of this invention, the outer steel plate is hoisted in sections by a tower crane, and the position is adjusted with a chain hoist to match the hoisting capacity of the tower crane and ensure installation safety; the steel plate joint strips, multi-layer continuous welding, and the support frame is equipped with scissor bracing and horizontal thrust resistance structure to further improve the structural integrity and stability of the closure block.

[0093] 5. The core of the process of this invention is the cost reduction and efficiency improvement through the reuse of hanging formwork. By retaining the bottom formwork and recombining and reusing the hanging formwork, there is no need to manufacture new hanging formwork, the equipment utilization rate is increased by more than 50%, there is no need for full-span scaffolding, the number of procedures is reduced by 30%, and the closure cycle is shortened by 20% to 30%. It is suitable for the closure construction of the triangular area of ​​large-span concrete hollow rigid frame bridges and has good promotion and application value.

[0094] The above examples illustrate the present invention only to aid in understanding it and are not intended to limit the scope of the invention. Those skilled in the art can make various simple deductions, modifications, or substitutions based on the principles of this invention.

Claims

1. A novel closure process for the triangular section of a hollow rigid frame bridge, characterized in that: The closure process includes: The lower chord of the hollow rigid frame bridge was constructed using the lower chord triangular hanging basket (1) until the lower chord X10# block (2) was completed. The upper chord of the hollow rigid frame bridge is constructed using the upper chord diamond hanging basket (6) until the upper chord S9# block (3) is completed. The lower chord hanging basket bottom formwork system (4) is temporarily anchored to the bottom plate of the beam segment of lower chord X10# block (2), and then the lower chord triangular hanging basket (1) is removed. Move the upper chord diamond hanging basket (6) to the position of the upper chord S10# block (8), remove the upper chord hanging basket bottom mold system (7), and install the upper and lower chord tube column temporary locking device (9) between the upper chord S9# block (3) and the lower chord X9# block (17) to complete the temporary locking of the upper and lower chords in the triangular area; Install the bottom and web fastener type steel pipe support (10) of the upper chord S10# block (2) on the top plate of the beam segment of the lower chord X10# block (2), and construct the upper chord S10# block (8). The lower chord hanging basket bottom mold system (4) and the upper chord diamond hanging basket (6) are connected to each other by a hanging rod to form the recombined solid belly area upper chord hanging basket (11), and then moved to the position of the closing block 11# block (12); The closure block 11# (12) was constructed in two horizontal layers, with the horizontal layer section being the top of the lower chord box girder.

2. The novel hollow rigid frame bridge triangular section closure process according to claim 1, characterized in that: The upper and lower chord column type temporary locking device (9) includes a vertical column and an inclined tube body intersecting between adjacent vertical columns; The upper and lower ends of the vertical column are respectively fixed to the bottom plate of the upper chord S9# block (3) and the top plate of the lower chord X9# block (17).

3. The novel hollow rigid frame bridge triangular section closure process according to claim 2, characterized in that: The upper chord S10# block bottom and web plate fastener type steel pipe support (10) includes a lattice frame body composed of uprights (1001) and longitudinal and transverse horizontal bars (1002). The upper and lower parts of the lattice frame body are provided with diagonal sweeping bars (1003), and the lattice frame body is provided with X-shaped scissor braces (1004). The intersection of the upright (1001) and the longitudinal and transverse horizontal bars (1002) is fixed by fasteners; The top of the upright (1001) is connected to the U-shaped top support (1005), and a pad (1006) is provided between the U-shaped top support (1005) and the bottom plate of the beam segment of the upper chord S10# block (8).

4. The novel hollow rigid frame bridge triangular section closure process according to claim 3, characterized in that: Construction of the upper chord S10# block (8) includes: The upper chord diamond hanging basket (6) provides the outer mold and inner mold, and together with the upper chord S10# block bottom and web plate fastener steel pipe support (10) to construct the upper chord S10# block (8). During the installation of reinforcing bars, the vertical prestressing tendons along the entire length of the upper and lower chords are laid out in advance. The prestressing ducts are positioned using a grid-shaped steel bar, and the grid-shaped steel bar is spot-welded to the vertical prestressing tendons along the entire length for fixation.

5. The novel hollow rigid frame bridge triangular section closure process according to claim 4, characterized in that: In the reconstructed solid abdominal region upper chord hanging basket (11), the outer mold of the upper chord rhomboid hanging basket (6) is extended and connected to the outer mold (5) of the lower chord triangular hanging basket (1).

6. The novel hollow rigid frame bridge triangular section closure process according to claim 5, characterized in that: The outer steel plate of the closure block 11# (12) includes the side plate and the outer steel plate (16) of the intersection area of ​​the upper and lower chords. The outer steel plate (16) of the intersection area of ​​the upper and lower chords includes the top plate of the lower chord, the arc plate and the bottom plate of the upper chord.

7. The novel hollow rigid frame bridge triangular section closure process according to claim 6, characterized in that: The first construction of closure block 11# (12) includes: Install the side plates of the lower chord box girder section; Install the top plate of the lower chord and the arc plate in the outer steel plate (16) of the intersection area of ​​the upper and lower chords as the lower pressure plate; Combine the lower chord hanging basket bottom formwork system (4) to pour the lower chord box girder.

8. The novel hollow rigid frame bridge triangular section closure process according to claim 7, characterized in that: When the closure block 11# (12) was constructed for the first time, a vibration hole was reserved on the top plate of the lower chord of the steel plate (16) outside the intersection of the upper and lower chords for concrete vibration.

9. The novel hollow rigid frame bridge triangular section closure process according to claim 8, characterized in that: The second construction of closure block 11# (12) includes: Install the side plates of the upper chord box girder section; Install the bottom plate of the upper chord in the outer steel plate (16) of the intersection area of ​​the upper and lower chords; Using the concrete surface from the first construction as support, the upper chord box girder section was poured.

10. The novel hollow rigid frame bridge triangular section closure process according to claim 9, characterized in that: During the second construction of the closure block 11# (12), a support frame was erected on the top of the lower chord top plate of the outer steel plate (16) of the upper and lower chord intersection area, and the top of the support frame supported the bottom plate of the upper chord of the outer steel plate (16) of the upper and lower chord intersection area.

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