Process for prefabricating and hoisting web reinforcements of single-box three-chamber large-section suspended cast box girder

Abstract

The invention discloses a process for prefabricating and hoisting web reinforcing steel bars of a single-box three-chamber large-section suspended cast box girder. The process comprises a web reinforcing steel bar integral prefabricating process and a web reinforcing steel bar integral hoisting process. The web steel bar overall prefabricating process is carried out on the ground through a steel bar binding clamping fixture and used for horizontally binding web steel bars. When the web steel bars are integrally prefabricated, the method comprises the following steps of steel bar binding mouldmanufacturing, stirrup binding, hoisting stiff framework installation, end formwork installation, longitudinal steel bar installation and prestressed bar installation. The web steel bar integral hoisting process comprises the following steps of hoisting point setting, integral hoisting and integral in-mold installation. According to the process for prefabricating and hoisting the single-box three-chamber large-section suspended cast box girder web reinforcing steel bars, the modular prefabricated web reinforcing steel bars are adopted, the defects that due to the fact that the web reinforcingsteel bars are directly bound in a hanging basket formwork, the operation space is narrow, and procedures interfere with one another are avoided, operation is convenient and fast, safety is high, andthe operation time of girder construction is effectively shortened.

Description

technical field [0001] The invention relates to a bridge-building technology, in particular to a prefabrication and hoisting technology of a single-box three-chamber large-section cantilevered box girder web reinforcement. Background technique [0002] The newly built Jiantan Dongjiang Super Bridge is the widest four-line high-speed railway bridge in China, and the main bridge span is 260m prestressed concrete low-tower cable-stayed bridge. Its main girder is a prestressed concrete box girder, which adopts a variable-height single-box three-chamber oblique web section, and the side webs are oblique webs; The whole girder bottom changes according to a parabola. The top width of the box girder is 31.2m, and the bottom width changes from 22.61m at the side fulcrum and mid-span to 19.11m at the middle fulcrum. The continuous box girder of the main span is divided into more than 60 sections for construction, and the hanging basket cantilever pouring method is used for constructi...

AI Technical Summary

Problems solved by technology

The installation process of steel bars for the oblique web of a single-box multi-chamber large-scale cantilevered box girder with a large section is more complicated than that of a small-section cantilevered box girder. Since the maximum height of the oblique web of this box girder reaches 13m, it increases Installation Difficulty and Safety Risks of Web Reinforcement

Since there are 8 webs in one section of cantilever pouring, the construction of each web reinforcement consists of multiple processes such as stirrups, longitudinal distribution bars, longitudinal prestressed pipes, vertical prestressing, and end formwork installation. Many and complicated. When operators perform steel bar binding and prestressed installation operations in the hanging basket formwork, the construction speed is slow and the work efficiency is low. It is difficult to improve work efficiency. At the same time, there are hidden dangers of unsafe operation

The construction time of each web reinforcement is 48 hours, and 6 operators are required at the same time

Images