Hinged joint structure with compound shear key and its prefabricated slab bridge

Abstract

The invention discloses a hinge joint structure with composite shear keys, which comprises a plurality of precast slabs, a hinge joint is formed between the precast slabs, and connecting keys which can transfer horizontal shearing force and vertical shearing force and are integrally connected with the precast slabs and the hinge joint are transversely distributed on the hinge joint; the connecting keys are stiffened steel plates with bolted shear keys which span the hinge joint and are fixed on the surfaces of the precast slabs at both sides of the hinge joint, and the stiffened steel plates are provided with through holes capable of transferring horizontal shearing force which correspond to the hinge joint; the stiffened steel plates with the through holes are shear keys, horizontal shearing force is transferred by the through holes and vertical shearing force is transferred by the stiffened steel plates, so that the force transfer property is enhanced, and thereby the stiffness and overall performance of the structure are enhanced; the bolted shear keys can transfer horizontal shearing force and enhance connection property. The coordinate deformation of a bridge deck pavement, the hinge joint and the precast slabs is ensured, the load transfer capability of the hinge joint structure is enhanced, the service life of the hinge joint structure is prolonged, maintenance cost is reduced, construction is simple and convenient, the hinge joint structure can be applied in the construction of new precast slab bridges or the maintenance and reinforcement of precast slab bridges, and effectively solves the defect of insufficient shear-resisting capability existing in precast slab bridges, and the integrity and force-transferring effectiveness of the structure are increased.

Description

technical field [0001] The invention relates to the field of civil engineering, in particular to a hinged joint structure with composite shear keys and a prefabricated slab bridge thereof. Background technique [0002] At present, domestic measures to improve the overall performance of precast slab bridges can be roughly divided into two categories: one is to improve the overall performance of the transverse direction, and the other is to improve the hinge joint structure. There are two main ways to improve the overall transverse performance: (1) Transverse prestressed steel tendons, setting external prestressed steel tendons at the middle and end of the span or setting a diaphragm beam in the middle of the span and passing prestressed steel tendons inside the beam , this measure involves prestressed construction technology, and the operation is relatively complicated; (2) implant anchor bolts at the bottom of the adjacent prefabricated slabs on both sides of the hinge joint...

AI Technical Summary

Problems solved by technology

There are two main ways to improve the overall transverse performance: (1) Transverse prestressed steel tendons, setting external prestressed steel tendons at the middle and end of the span or setting a diaphragm beam in the middle of the span and passing prestressed steel tendons inside the beam , this measure involves prestressed construction technology, and the operation is relatively complicated; (2) implant anchor bolts at the bottom of the adjacent prefabricated slabs on both sides of the hinge joint to set up connecting steel plates or connecting bars, or pre-embed angle steel and implement welding , so that the deformation between adjacent slabs is coordinated, such measures will cause longitudinal cracks in the bridge deck pavement on the top of the precast slab and will affect the clearance under the bridge to a certain extent. If welding is used, the concrete will also be damaged; (3) through Reinforced concrete integral bridge deck pavement improves the integrity of the structure. This method has a long construction period, affects the traffic operation of bridges that have been opened to traffic, and provides less shear stiffness.

The improvement of the hinge joint structure is concentrated in two types of measures: (1) the cross reinforcement is generally replaced by the nearly elliptical stirrup in the hinge joint, and the mechanical concept of this kind of measure is not clear; Structural steel bars need to be close to the side formwork during prefabrication, and need to be pulled out after the formwork is removed. If the steel bar does not fit tightly with the side formwork, the steel bar will be buried in the concrete, making it difficult to find the steel bar and causing difficult or fundamental problems. It cannot be bent out, even if the specific position of the hinged steel bar can be found out, the concrete needs to be chiseled before bending, the workload and work intensity are relatively large, and the shear rigidity provided is small

Images