Prefabricated assembled hollow pier based on UHPC joints and construction method

Abstract

The invention discloses a prefabricated assembled hollow pier based on UHPC joints and a construction method of the pier, the prefabricated assembled hollow pier comprises a pier column and a base, the pier column is a hollow pier column, the pier column is sequentially composed of a pier bottom section, a middle section and a top cap section from bottom to top, the pier bottom section is located at the top of the base, steel bar connectors are embedded between the pier bottom section and the base, between the pier bottom section and the middle section and between the middle section and the top cap section, reinforcing stirrups are arranged outside the steel bar connectors, and connection is achieved through post-pouring of UHPC joints. According to the invention, the steel bar connectors between the sections are easy to position and connect, the height of the joints is remarkably reduced, and the using amount of joint concrete is small; the segment construction tolerance is large, and the precision requirement is low; joints are free of vibration, self-compaction is achieved, pouring is convenient, and construction is simple; and the assembled pier is excellent in overall performance, high in joint durability, rapid to assemble, short in field operation time and high in efficiency.

Description

technical field [0001] The invention relates to the field of bridge construction, in particular to a prefabricated assembled hollow pier based on UHPC joints and a construction method. Background technique [0002] Segmental prefabricated assembled pier construction, as one of the rapid construction technologies for bridges, has been applied in domestic and foreign highway municipal projects and sea-crossing long bridge projects. It is more difficult, and the use of prefabricated assembly has greater advantages. As one of the most basic pier types in bridge pier structures, hollow piers have the advantages of high rigidity and light segmental weight, and are widely used in prefabricated assembled bridge piers. [0003] At present, segmental prefabricated assembled hollow piers are generally assembled by post-cast concrete joints or prestressed connections. Post-cast concrete joints refer to prefabricating the segments in the factory, and reserve a line or U-shaped steel ba...

AI Technical Summary

Problems solved by technology

[0004] 1. It is difficult to align and connect the steel bar joints. The use of welded in-line steel bars requires one-to-one butt welding of the steel bars. The precise alignment of the steel bars is difficult and the welding process is complicated; the U-shaped steel bar joints need to be equipped with stronger reinforcement.

At the same time, the joint steel bars in the segments need to reserve a long length, which is not convenient for manufacturing

[0005] 2. The post-cast concrete joints need to be high in height. In order to realize the post-cast concrete’s grip and force transmission on the steel bars, and the joints of the steel bars need to be staggered, the joint height generally needs to be more than 35 times the diameter of the connected steel bars, which greatly increases the joint strength. The height of the joint, resulting in a large amount of post-cast concrete

[0006] 3. The joints of post-cast concrete need to be vibrated and maintained. The concrete construction process is relatively complicated, and the strength of the connection surface with precast concrete is low, which is easy to cause shrinkage cracks. The cracks may become corrosion channels and affect the durability of the structure

[0007] 4. Due to the existence of processes such as the parallel connection of steel bars in the joints of post-cast concrete, the amount of concrete pouring is large, the joint operation time is slightly longer, and the efficiency is slightly lower

[0009] 1. The manufacturing precision of the segments is high, and each segment must be completely matched, and the construction tolerance is small. Generally, 2-3mm epoxy resin glue is installed between the segments, and the thickness is small, which is not conducive to the error adjustment of the segment connection surface. The larger section increases the difficulty of construction

[0010] 2. Thick steel bars or high-strength steel rods are used for prestressing, which requires tensile prestressing. The prestressing tension and grouting process requirements are high, and there is a risk of loss or even failure in the later stage of prestressing. This connection form has poor ductility and insufficient energy consumption, so it is not suitable In high earthquake area

[0011] 3. The overall quality control of prestressed connections is difficult, and the used connection materials such as prestressed beams, epoxy resin glue, etc. have high requirements for durability, and require high protection measures when used in harsh corrosive environments such as cross-sea projects

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