Do You Know The Structural Characteristics Of Steel Cable-stayed Bridges?

Anchor box type anchoring structure

The anchor box type anchoring structure is a box-shaped structure welded on the outside of the web, and the cable is anchored on the pressure plate of the anchor box. It is mainly composed of two anchor plates, the pressure plate, the stiffening plate between the anchor plates, and the stiffening of the anchor plate. It consists of a board and a backing board.

The structural features are as follows:

(1) A wedge-shaped pressure bearing plate is used to adapt to the different inclination angles of each stay cable in the transverse direction.

(2) A built-in damper can be used to reduce the vibration of the stay cable, and it can ensure that the damper is firmly connected to the main beam, and can give full play to the role of the damper.

(3) There are no special requirements for structural materials, which can be met by general bridge steel.

(4) The anchor head of the cable is placed in the tuyere, which has a good landscape effect, but it is inconvenient for inspection and maintenance.

(5) The cable can be stretched at both the tower end and the beam end.

Pin hinge anchoring structure

The pin-hinged anchoring structure is to extend the web of the beam or connect the ear plate to the web through a high-strength bolt, and the stay cable is hinged to the ear plate through a pin.

The structural features are as follows:

(1) The bolt connection type is to set the ear plate on the outside of the web plate, and the ear plate is designed to be wedge-shaped to adapt to the different lateral inclination angles of the stay cables; while the web extension type is to adapt to the different lateral inclination angles of the stay cables. Special measures are taken at the anchor head of the cable.

(2) Since the stay cable is higher from the bridge deck and can rotate with the pin shaft, it cannot guarantee that the damper is firmly connected to the main girder. Therefore, the built-in damper is not ideal for suppressing the cable vibration.

(3) Because the ear plate (web plate) has great local stress near the pin hole, the steel requirements are very high.

(4) The structure is simple, which is convenient for installation and daily maintenance, but the exposed parts of the system are not beautiful.

Anchor pipe anchoring structure

The anchor pipe anchoring structure is to disconnect the web at the anchor point and weld the anchor pipe structure. The cable is anchored on the pressure plate at the end of the anchor pipe, and the cable force is transmitted to the web of the main beam through the steel pipe.

The structural features are as follows:

(1) The use of wedge-shaped pressure-bearing backing plates can adapt to cable stays with different lateral inclination angles.

(2) A built-in damper can be used to reduce the vibration of the cable, and it can ensure that the damper is firmly connected to the main beam and can give full play to the role of the damper.

(3) The anchor head is exposed at the bottom of the beam, which is inconvenient for daily maintenance and unsightly.

(4) The stay cable easily collides with the pipe wall at the exit of the anchor pipe.

(5) There are no special requirements for structural materials, which can be met by general bridge steel.

(6) The cable can be stretched at the tower end and beam end

Pull-plate anchoring structure

Pull-plate connection is to use steel plate as the upper part of the pull-plate. The inner side of the notch is welded to the outer side of the anchor pipe. The stay cable passes through the anchor pipe and is anchored to the bottom of the anchor pipe. The lower part is directly welded to the top edge of the main beam with welds.

The structural features are as follows:

(1) The use of wedge-shaped pressure-bearing backing plates can adapt to the different lateral inclination angles of the stay cables, and the fixed inclination angle of the web can be used to reduce the manufacturing difficulty.

(2) The structure is simple, which is convenient for installation and daily maintenance, but the system is not beautiful when exposed.

(3) There are no special requirements for structural materials, which can be met by general bridge steel.

(4) The cable can only be stretched at the end of the tower.