Segmental assembly type pier capping beam

Abstract

The utility model belongs to the technical field of bridge construction, and particularly relates to a segment assembly type pier capping beam. The bent cap is formed by splicing a prefabricated bent cap left section and a prefabricated bent cap right section through a bracket type joint in the length direction. The bracket type joint comprises a bracket fulcrum extending from the lower part of the splicing side of the left section of the cover beam and a cantilever structure extending from the upper part of the splicing side of the right section of the cover beam, and the bracket fulcrum and the cantilever structure form two vertical splicing surfaces and a horizontal splicing surface; the splicing face of the left bent cap section and the splicing face of the right bent cap section are coated with epoxy adhesives, corresponding reserved holes are formed in the two bent cap sections, and a continuous prestressed tendon channel is formed after the two bent cap sections are spliced. The workload of the installation construction site of the cover beam is small, the installation process is simple, convenient and rapid, no support or formwork needs to be erected, and the construction safety degree is improved.

Description

Technical Field

[0001] This utility model belongs to the field of bridge construction technology, specifically relating to a segmental prefabricated bridge pier cap beam. Background Technology

[0002] Precast bridges have been rapidly adopted in the engineering field due to their numerous advantages, including fast construction speed, high engineering quality, labor savings, and reduced traffic and environmental impact. However, compared to the superstructure, the cap beams in the substructure are significantly heavier, posing considerable challenges to transportation and hoisting. Lightweighting of cap beams can be achieved in two ways: 1. reducing the weight of components by segmenting or dividing them into sections; 2. reducing the weight of components by using new structures or materials. Segmenting or dividing components reduces their size and weight, thus simplifying transportation and hoisting. Currently, this method is commonly used in precast assembly projects in China. Segmenting cap beams is a preferred method for weight reduction among engineers, generally taking two forms: the first form has the joint at the mid-span of the cap beam, suitable for both large and small column spacing; the second form has the joint on the cantilever arm of the cap beam outside the columns, suitable for smaller column spacing.

[0003] For cap beams with cast-in-place joints at mid-span, the conventional approach is to connect the cap beam and the column using sleeves or grouted corrugated pipes, leaving a relatively wide cast-in-place joint at mid-span, and then connecting the reinforcing bars passing through the joint by welding. However, this connection method involves a large amount of on-site work and is cumbersome to construct. If a reliable and efficient segmental prefabricated cap beam could be provided, eliminating the need for scaffolding and formwork, it would be much easier to construct and would facilitate the promotion of prefabricated cap beams. Utility Model Content

[0004] In view of this, the purpose of this utility model is to provide a segmental prefabricated bridge pier cap beam. This type of cap beam requires less on-site construction work, has a simple and quick installation process, and eliminates the need for scaffolding or formwork, thus improving construction safety.

[0005] To achieve the above objectives, this utility model is implemented through the following technical solution:

[0006] A segmental prefabricated bridge pier cap beam is provided, wherein the cap beam is spliced ​​along its length by a precast left segment and a precast right segment via a corbel joint. The corbel joint includes a corbel support extending from the lower part of the splicing side of the left segment and a cantilever structure extending from the upper part of the splicing side of the right segment, forming two vertical splicing surfaces and one horizontal splicing surface. The splicing surfaces of the left and right segments are coated with epoxy adhesive, and corresponding pre-reserved holes are provided in the two segments, forming a continuous prestressed tendon channel after splicing.

[0007] Furthermore, the connection node between the left segment of the cap beam and the pier includes a vertical grouting corrugated steel pipe pre-embedded in the left segment of the cap beam, and a pre-embedded main reinforcement extending from the top of the pier, wherein the pre-embedded main reinforcement is inserted into the grouting corrugated steel pipe; the connection node between the right segment of the cap beam and the pier includes a vertical grouting corrugated steel pipe pre-embedded in the right segment of the cap beam, and a grouting sleeve pre-embedded in the top of the pier, wherein a rear-inserted main reinforcement is inserted into the grouting sleeve.

[0008] Furthermore, prestressing tendons are installed in the prestressing tendon channel to apply permanent prestress so that the cap beam forms an integral structure.

[0009] Furthermore, temporary anchor blocks are provided on the upper side of the left and right segments of the precast cap beam. The splicing surface of the corbel joint is tightly fitted by horizontal temporary prestressing. The temporary prestressing is applied by tensioning the prestressed steel bars through the temporary anchor blocks and jacks.

[0010] Correspondingly, this utility model also provides an installation method for segmental prefabricated bridge pier cap beams, including the following steps:

[0011] A. Install the left segment of the cap beam, and insert the pre-embedded main reinforcement extending from the top of the pier column into the pre-embedded corrugated steel pipe for grouting the reinforcement of the left segment of the cap beam;

[0012] B. Clean the splicing surfaces of the left and right segments of the cap beam and apply epoxy adhesive;

[0013] C. Install the right segment of the cap beam, leaving a gap between it and the left segment of the cap beam;

[0014] D. By tensioning the prestressed steel bars with temporary anchor blocks and jacks, horizontal temporary prestress is applied, so that the right segment of the cap beam is translated and closely fits the left segment of the cap beam;

[0015] E. Insert the rear-inserted main reinforcement from the top of the right segment of the cap beam, so that it extends into the grouting sleeve of the reinforcement at the top of the pier column;

[0016] F. After the epoxy adhesive has cured, apply permanent prestress within the prestressing tendon channel;

[0017] G. Remove the temporary prestressing device;

[0018] H. Grouting treatment is performed on the corrugated steel pipes and grouting sleeves for reinforcing bars.

[0019] Compared with the prior art, the present invention has the following beneficial technical effects:

[0020] By dividing the cap beam into two prefabricated segments along its length, the weight of each segment is significantly reduced, solving the transportation and hoisting difficulties caused by the excessive weight of traditional monolithic cap beams. The corbel-style joint design further optimizes the splicing method between segments, avoiding complex cast-in-place joint construction and simplifying on-site operations.

[0021] The use of epoxy adhesive to bond the splicing surfaces, combined with horizontal temporary prestressing tensioning technology, enables the segments to be quickly and tightly bonded without the need for scaffolding and formwork. This reduces the risks of working at heights and the consumption of auxiliary materials, significantly shortens the construction period, and improves on-site safety.

[0022] The continuous prestressed tendon channel formed by the splicing of pre-reserved holes can be permanently prestressed after curing. Combined with the grouting filling of the corrugated steel pipe and sleeve, it ensures the rigid connection between the segment and the pier, effectively improving the overall load-bearing capacity and long-term durability of the cap beam.

[0023] The cap beam consists of two precast segments, manufactured in a standardized factory. On-site assembly only requires hoisting, eliminating the need for cast-in-place concrete and thus removing the formwork support system required in traditional cast-in-place processes. The segments utilize a corbel-style joint design, where a tight fit between the splicing surfaces and application of epoxy adhesive, supplemented by temporary horizontal prestressing, ensures rapid and tight bonding. This combination of mechanical interlocking and chemical bonding eliminates the need for additional formwork to fix the joint position. After assembly, permanent prestress is applied through pre-drilled holes, forming a unified load-bearing structure that does not rely on formwork or supports to maintain segment stability. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the installation stage of a preferred embodiment of the present invention;

[0025] Figure 2 This is a schematic diagram of the bridge construction stage of a preferred embodiment of the present invention;

[0026] In the diagram: 1. Left segment of cap beam; 2. Right segment of cap beam; 3. Corbel joint; 4. Pier column; 5. Corrugated steel pipe with grouting; 6. Embedded main reinforcement; 7. Grouting sleeve; 8. Temporary anchor block; 9. Jack; 10. Prestressed steel reinforcement; 11. Post-inserted main reinforcement; 12. Prestressed tendon channel. Detailed Implementation

[0027] The present invention will be further described in detail below with reference to the accompanying drawings and specific examples. It should be noted that the drawings are all in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the explanation of the present invention. The descriptions are merely of preferred embodiments of the present invention and are not intended to limit the present invention in any way. Any changes or modifications made by those skilled in the art based on the above disclosure shall fall within the scope of protection of the claims.

[0028] Please refer to Figure 1As shown, a segmental prefabricated bridge pier cap beam is constructed by splicing two prefabricated cap beam segments along the length of the cap beam, namely the left segment 1 and the right segment 2. The joint between the cap beam segments is a corbel joint 3.

[0029] As shown in the figure, the connection node between the left segment 1 of the cap beam and the pier 4 adopts the form of pre-embedded grouted corrugated steel pipe 5 of the left segment 1 of the cap beam and pre-embedded main reinforcement 6 extending from the top of the pier 4. The connection node between the right segment 2 of the cap beam and the pier 4 adopts the form of pre-embedded grouted corrugated steel pipe 5 of the right segment 2 of the cap beam and pre-embedded grouted sleeve 7 of the pier 4. The pre-embedded grouted corrugated steel pipe 5 vertically penetrates the cap beam segment and is open at both ends.

[0030] As shown in the figure, the lower part of the left segment 1 of the cap beam extends out on the splicing side to form a corbel support point; the upper part of the right segment 2 of the cap beam extends out on the splicing side to form a cantilever structure; the corbel support point and the cantilever structure form two vertical splicing surfaces and one horizontal splicing surface, and the splicing surfaces of the left segment 1 and the right segment 2 of the cap beam fit together tightly.

[0031] As shown in the figure, during construction, the left segment 1 of the cap beam is installed first, and the pre-embedded main reinforcement 6 extending from the top of the pier column 4 is completely inserted into the pre-embedded corrugated steel pipe 5 of the left segment 1 of the cap beam. Then, the splicing surfaces of the two cap beam segments are cleaned and coated with epoxy adhesive. Next, the right segment 2 of the cap beam is installed in place. Temporary anchor blocks 8 are installed on the cap beam segments, and horizontal temporary prestress is applied by tensioning the prestressed steel bars 10 between the corresponding anchor blocks 8 using jacks 9, so that the left segment 1 and the right segment 2 of the cap beam are tightly fitted together. Then, grout is poured into the pre-embedded steel bars from the top of the right segment 2 of the cap beam. The main reinforcing bar 11 is inserted into the corrugated steel pipe 5, and the main reinforcing bar 11 extends into the pre-embedded steel bar grouting sleeve 7 at the top of the pier column, connecting the right segment 2 of the cap beam and the lower pier column 4; the two precast cap beam segments are provided with corresponding reserved holes. After splicing into an integral cap beam, the reserved holes are connected to form a continuous prestressing tendon channel 12. Prestressing tendons can be installed in the prestressing tendon channel 12. After the adhesive cures, permanent prestress is applied and the temporary prestress is removed; finally, the grouting of the corrugated steel pipe 5 and the steel bar grouting sleeve 7 in the connection node between the cap beam and the pier column 4 is completed.

[0032] This utility model is applicable to cap beams of any structural form, and is suitable for both cases with large and small pier spacing.

[0033] This invention significantly reduces the weight of precast cap beams, simplifies transportation and hoisting, minimizes on-site work, simplifies and speeds up installation, and eliminates the need for scaffolding and formwork, thus improving construction safety. It offers excellent economic, technological, and social benefits and is worthy of promotion and application.

[0034] The above are merely preferred embodiments of the present utility model and are not intended to limit the implementation methods and protection scope of the present utility model. Those skilled in the art should realize that any equivalent substitutions and obvious changes made based on the description and illustrations of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A segmental prefabricated bridge pier cap beam, characterized in that, The cap beam is formed by splicing a precast left segment (1) and a precast right segment (2) along its length through a corbel joint (3); the corbel joint (3) includes a corbel support extending from the lower part of the splicing side of the left segment (1) and a cantilever structure extending from the upper part of the splicing side of the right segment (2), forming two vertical splicing surfaces and one horizontal splicing surface; the splicing surfaces of the left segment (1) and the right segment (2) are coated with epoxy adhesive, and corresponding reserved holes are provided in the two segments, forming a continuous prestressed tendon channel (12) after splicing.

2. The segmental prefabricated bridge pier cap beam according to claim 1, characterized in that, The connection node between the left segment (1) of the cap beam and the pier (4) includes a vertical grouting corrugated steel pipe (5) pre-embedded in the left segment (1) of the cap beam, and a pre-embedded main reinforcement (6) extending from the top of the pier (4), wherein the pre-embedded main reinforcement (6) is inserted into the grouting corrugated steel pipe (5); the connection node between the right segment (2) of the cap beam and the pier (4) includes a vertical grouting corrugated steel pipe (5) pre-embedded in the right segment (2) of the cap beam, and a grouting sleeve (7) pre-embedded in the top of the pier (4), wherein a rear-inserted main reinforcement (11) is inserted into the grouting sleeve (7).

3. The segmental prefabricated bridge pier cap beam according to claim 1, characterized in that, The prestressed tendon channel (12) is equipped with prestressed tendons, which are used to apply permanent prestress to make the cap beam form an integral structure.

4. The segmental prefabricated bridge pier cap beam according to claim 1, characterized in that, Temporary anchor blocks (8) are provided on the upper side of the left and right segments of the precast cap beam. The splicing surface of the corbel joint (3) is tightly fitted by horizontal temporary prestressing. The temporary prestressing is applied by tensioning the prestressed steel bars (10) through the temporary anchor blocks (8) and jacks (9).

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