Self-balancing arch rib vertical rotation and lift construction method

Abstract

The invention provides a self-balancing arch rib vertical rotation and lift construction method. The method has the following beneficial effects that: the terrain characteristics of the plains are considered, the idea of turning vertical force into horizontal force in the traditional vertical rotation method is abandoned, the characteristic of strong vertical bearing capacity of the tower is fully used, and the position of the tower, arrangement of upper and lower anchor points of the system and arrangement of various standard steels of the tower are improved to ensure the transfer path of the tower load to be simple and definite, ensure the horizontal force in the vertical rotation process to be as low as possible and be even zero and form a tower system with strong resistance and high horizontal force, thus utilizing the capacity of the tower to balance the horizontal force generated in the vertical rotation process and forming the self-balancing arch rib vertical rotation and lift technology, without rear anchor cables; therefore the construction difficulty of arch bridges, especially large span arch bridges in the plains can be greatly reduced. The method provided by the invention has the characteristics of high construction safety, good economy, strong operability and the like and is suitable for installation of arch ribs in the plains.

Description

technical field [0001] The invention relates to a construction method for vertically rotating and lifting arch ribs in bridge construction. Background technique [0002] Because the bridge swivel construction has the characteristics of saving hoisting costs, reducing high-altitude operations, convenient and flexible construction operations, safety, reliability, and good integrity, easy adjustment and control of structural alignment and internal forces, and avoiding interference to normal traffic under the bridge, it has become a popular choice for bridges at home and abroad. It has been widely used in construction and is constantly developing. At present, there are mainly two changes in the vertical rotation technology of arch ribs. One is the vertical rotation technology formed for the special geographical conditions in mountainous areas - negative angle vertical rotation. The traditional vertical rotation is assembled at a low level, and then raised to high The negative a...

AI Technical Summary

Problems solved by technology

[0003] (1) The vertical rotation of the arch rib still adopts the original concept of vertical rotation: the tower is under compression and the anchor cable balances the horizontal force. Therefore, it is still inevitable to install anchor cables and corresponding anchoring devices in this type of system. The change of the buckle cable force is used to adjust the anchor cable force. The setting of the anchor device and the frequent adjustment of the rear anchor cable will inevitably bring greater safety hazards.

[0004] (2) There is a lack of a unified calculation method for the calculation of the buckle cable force

However, the current calculation method still uses the moment balance method to calculate the force arm, which is still feasible for simple individual working conditions. If there are many working conditions or vertical rotation system optimization, the workload will be too large

[0005] (3) When the span of the arch rib is large, the use of this technology will cause a large difference between the line shape and stress of the arch rib during the construction period and the state of the bridge. If it is not eliminated by a certain method, then the mechanical state of the arch rib after closing It will be quite different from the design state, and there is still a lack of systematic discussion on the closing method of arch ribs and structural measures suitable for this type of construction method.

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