Method for reinforcing hogging moment area of continuous beam by adopting steel fiber self-stress concrete

Abstract

The invention provides a method for reinforcing a hogging moment area of a continuous beam by adopting steel fiber self-stress concrete, the method comprises the following steps: pouring the steel fiber self-stress concrete into a hogging moment area at the top of a pier, and obliquely inserting an inserted vibrator into the steel fiber self-stress concrete for vibrating; and maintaining. The invention provides the method for reinforcing the hogging moment area of the continuous beam by adopting the steel fiber self-stress concrete, which is used for new bridge construction or reinforcing maintenance of bridge engineering, and is particularly applied to reinforcing of the hogging moment area of the continuous beam, and the steel fiber self-stress concrete is applied to popularization and utilization of the hogging moment area of the continuous beam, te method can replace a method for tensioning hogging moment prestressed steel beams in a hogging moment area at the top of a continuous beam pier, the tensile stress generated under the effects of self weight, second-stage dead load and automobile load is balanced through the pre-compressive stress generated by the steel fiber self-stress concrete, the design concept is clear, the construction safety is good, the economic benefit is good, and traffic can be opened as soon as possible.

Description

technical field [0001] The invention belongs to the technical field of new bridge construction, reinforcement and maintenance of bridge engineering, and in particular relates to a method for reinforcing the negative moment area of ​​a continuous beam with steel fiber self-stress concrete. Background technique [0002] Prestressed concrete prefabricated continuous beam is one of the most widely used structural forms in modern bridges. The load-bearing structure of continuous beams (T-beams, box-shaped beams) continuously spans several bridge spans to form a super statically indeterminate structure, which has outstanding advantages such as large structural rigidity, small deformation, less expansion joints, and smooth and comfortable driving. It is beneficial to meet the requirements of modern high-speed driving. Compared with simply supported beams with the same span, continuous beams have small section size, light weight, and less positive moment prestressed steel tendons. ...

AI Technical Summary

Problems solved by technology

The construction of negative moment prestressed steel tendons on the top of continuous beam pier is often prone to quality problems, resulting in insufficient negative moment prestressed. The main reasons are as follows: (1) Prestressed flat bellows and flat anchor heads are mostly used for negative moment steel tendons The tunnel is narrow, which is not conducive to the threading and grouting of negative moment steel beams; (2) The construction method of negative moment steel beams is usually stretched at the lower edge of the flange after the beam is erected, which is inconvenient to operate and has a large safety risk; ( 3) The design distance between the roof reinforcement and the bellows is small, coupled with construction errors and disturbances during concrete pouring, will cause the bellows to have misalignment deviations in both the horizontal and vertical directions

[0004] Insufficient negative bending moment prestress will lead to serious consequences such as deflection of the beam body, structural cracks, and weakened bridge bearing capacity, failing to meet the design load level traffic requirements.

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