Assembly type continuous box girder hogging moment steel cable anchoring area structure and construction method thereof

Abstract

The invention relates to an assembly type continuous box girder hogging moment steel cable anchoring area structure and a construction method thereof. The assembly type continuous box girder hogging moment steel cable anchoring area structure comprises a prefabricated box girder, a prefabricated box girder top plate thickened section which is thickened inwards is arranged on a prefabricated box girder top plate, and steel cable tensioning preformed grooves are formed in the prefabricated box girder top plate thickened section. Transverse and longitudinal steel bar structures are arranged in the prefabricated box girder top plate thickened section. When the box girder is prefabricated, the parts, with the length within the length range of hogging moment steel cables, of the box girder top plate and the parts, extending through tensioning notches 10-15 cm, of the box girder top plate are thickened, and a top plate thickened section of about 30 cm is arranged at the thickened tail end fortransition to the normal thickness; when the top plate is thickened inwards, the requirements of a round anchorage device in a hogging moment area for tensioning and anchoring are met, and the assembly type continuous box girder hogging moment steel cable anchoring area structure has the advantages that the bridge deck pavement space does not need to be occupied; load-carrying steel bars on the lower layer of the top plate cannot be cut off, and the later-stage stress of the tensioning notches is improved; the steel cables are tensioned on the bridge deck, and the requirements for arranging more steel cables are met; the structural force of the hogging moment area is improved, and tensioning and grouting are facilitated.

Description

technical field [0001] The invention relates to the technical field of bridge construction engineering, in particular to an anchorage area structure and construction method of an assembled continuous box girder negative moment steel beam. Background technique [0002] Prefabricated simply supported structure continuous box girder is a commonly used bridge type in highway bridges. When the system is converted, it is necessary to set prestressed steel beams in the negative moment area of ​​the fulcrum. The reliability of force and the convenience of construction are very important. The negative bending moment steel beams of the current prefabricated simple-supported continuous box girder adopt flat anchors and flat corrugated pipes, and the anchorage area structure is the original cross-sectional structure of the box girder. The flat anchorage needs to stretch the steel strands one by one, the tensioning efficiency is low, and the supporting flat corrugated pipe has low rigid...

AI Technical Summary

Problems solved by technology

The flat anchorage needs to stretch the steel strands one by one, the tensioning efficiency is low, and the supporting flat corrugated pipe has low rigidity, which is easy to deform during construction, which affects the later beam penetration and grouting, and has a negative effect on the construction quality, structural stress and structural durability. Greater impact

For this reason, it needs to be changed to a circular bellows and a circular anchorage. The circular anchorage requires a larger size of the anchorage area, and the thickness of the box girder roof is small, which cannot meet the anchorage layout and force requirements. The common method is to upward or downward. Lower part thickened top plate

Thickening upwards will occupy the space of the pavement layer, and partial thickening downwards needs to cut off the main reinforcement of the roof deck, which is not conducive to the stress of the bridge deck

Images