External pre-stress construction method for chamber type bridge maintaining

Abstract

The invention discloses an external prestressing construction method for box bridge maintenance, which is characterized in that: 1). The position of an anchor block, a redirector and a shock absorberare decided according to external cable arranging mode for external prestressing; 2). The installation of the anchor block: 2.1). concrete base surface processing; 2.2). hole drilling, hole cleaning and reinforcing bar planting; 2.3). the installation of steel-bonded steel plate: the anchor block comprises a steel-bonded steel plate, a connecting plate and a stiffening plate; all anchor bolts arepenetrated through a corresponding fixing hole on the steel-bonded steel plate; 2.4). the installation of other steel plates for the anchor block; the connecting plate is welded with the steel-bondedsteel plate, the stiffening plate is welded with the steel-bonded steel plate and is provided with a through hole for external cable; 2.5). glue pouring for the steel-bonded steel plate: glue pouringis made between the steel-bonded steel plate and the concrete base surface for the anchor block; 3). Horizontal partition wall perforation; 4). The installation of a redirecting support and a dampingsupport; 5). The installation of the redirector; 6). Penetrating and tension of prestressing steel strand; 7). The installation of the shock absorber. The invention has the advantages of convenient construction, flexibility and stronger reliability.

Description

technical field [0001] The invention relates to an external prestressing construction method for box bridge maintenance. Background technique [0002] In order to limit the continued deflection of the beam body and increase the compressive stress reserve of the section, external cables are generally installed as one of the main measures to solve the deflection of the beam body during maintenance of box bridges. The existing external cables are directly anchored to the transverse partition wall, or anchored by newly poured concrete; when the transverse partition wall is too thin to fully bear the force of the external cable, or when there is no anchoring space behind the transverse partition wall, it is necessary to separately design the anchor block to bear the force; When the concrete transportation is inconvenient, the newly poured concrete cannot be used for anchoring; and when the beam body has been cracked, the moisture of the newly poured concrete is easy to enter the ...

AI Technical Summary

Problems solved by technology

The existing external cables are directly anchored to the transverse partition wall, or anchored by newly poured concrete; when the transverse partition wall is too thin to fully bear the force of the external cable, or when there is no anchoring space behind the transverse partition wall, it is necessary to separately design the anchor block to bear the force; When the concrete transportation is inconvenient, the newly poured concrete cannot be used for anchoring; and when the beam body has been cracked, the moisture of the newly poured concrete is easy to enter the beam body and corrode the steel bars and prestressed steel strands (or steel bars) in the beam body, so it cannot be used. Freshly poured concrete anchoring

Existing external prestressing construction methods have limitations

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