Method and device for anchoring changeable prestressing force of suspension bridge

Abstract

The invention discloses a suspension bridge anchor replaceable prestressing method and a device, wherein the method comprises: a, designing the preconditions of different phases, wherein a whole bunch of prestressing meets the endurance safety conditions of main cables and the short time status safety conditions when the n' pieces of cables are replaced and relaxed; b, latterly judging cables replacing conditions; c, the replacing type is the underpinning type with relaxed pieces less than n' pieces each time; d, cables replacing method, wherein the replacing adopts single or a plurality of pieces underpinning type, anchor removing pieces number n' is less than the number of the short time status safety conditions. The device comprises a beehive embedded pipe, a prestressing tendon, an anchor pad plate, an anchor plate, a clip, a check damper, a protection cover, a spiral reinforcement under anchor, an antisepsis grease, a hexagon steel sleeve, an anti-leakage end plate and an outer hexagon steel sleeve. The method of the invention is easy and convenient for replacements, safe and reliable, has simple structure, powerfully realizes the maintenance of the whole bunch of prestressing tendons, and greatly improves the bridges safety and reliability.

Description

technical field [0001] The present invention relates to the technical field of prestressing for suspension bridge anchors, more specifically to a method for replaceable prestressing of suspension bridge anchorages, and also to a replaceable prestressing device for bridge anchorages. Under the premise of effectively anchoring the main cable strands and ensuring the safety of the bridge, the multi-strand prestressing tendons that constitute the whole bundle of prestressing are replaced, so as to realize the unbonded prestressing structure of the bridge's later maintainability. Background technique [0002] The anchorage is the key structure for the suspension bridge to bear the force and load, and it plays the role of transmitting the tension of the main cable to the foundation. The force transmission method between the anchorage and the foundation is generally divided into two types: gravity anchorage and tunnel anchorage. The gravity type anchorage relies on the self-weight...

AI Technical Summary

Problems solved by technology

[0006] The main disadvantages of the bonded prestressing system filled with mortar are: (1) It is difficult to detect and maintain, and it is difficult to make an accurate judgment on the actual corrosion of the prestressed steel beam; (2) Due to the influence of the shrinkage of the mortar after curing, it is inevitable that micro Cracks, unreliable anti-corrosion; (3) The prestressed steel beams and anchor clips are bonded together through mortar curing, which cannot be replaced and maintained under the premise of ensuring structural integrity. It is a "one-time" prestressed system

[0008] The main disadvantage of the conventional non-bonded prestressed system for suspension bridge anchorage is that due to the large number of strands that make up the prestressed steel tendon, it is easy to twist when threading and stretching, and the curved sections are squeezed tightly, so they cannot be partially replaced, and cannot Perform safe replacement operations with no improvement in maintainability compared to bonded systems

[0009] Generally speaking, the traditional anchorage prestressing system has the main disadvantages: it is difficult to detect and maintain, and the replacement and maintenance of steel beams and clips cannot be realized on the premise of ensuring the safety of the bridge. Corrosion damage occurs to the sheet, and the safety and durability of the entire bridge will be seriously affected

Images