Method for reinforcing post-earthquake bridge pier through super-toughening fiber concrete

Abstract

The invention relates to the field of bridge pier reinforcing, in particular to a method for reinforcing a post-earthquake bridge pier through super-toughening fiber concrete. The damaged bridge pieris supported, failure concrete is chiseled away, a bearing platform face is roughened, and anchoring steel bars and original steel bars are welded; the original steel bars are welded, the anchoring steel bars in the super-toughening fiber concrete are laid, and the anchoring steel bars are welded to the original steel bars; a formwork is mounted, the super-toughening fiber concrete is poured, andafter completion, a vibration platform is adopted for vibration compaction; and the poured super-toughening fiber concrete is cured, after the mechanical index of the concrete meets the design requirement, the formwork is removed, and whole construction is completed. Owing to the fact that the post-earthquake bridge pier is reinforced through the super-toughening fiber concrete, the method has thecharacteristics of being small in thickness of the reinforced structure, large in rigidity, high in toughness, good in interlayer cohesiveness, good in durability and good in fatigue resistance.

Description

technical field [0001] The invention relates to the field of pier reinforcement, in particular to a method for reinforcing post-earthquake pier with super-tough fiber concrete. Background technique [0002] Bridge is a key hub in traffic engineering and an important node to ensure road traffic. Due to the structural characteristics of bridge engineering itself, it is extremely vulnerable to damage under extreme conditions such as earthquakes. In the past two decades, bridge structures have been severely damaged in previous major earthquakes at home and abroad, causing huge economic losses. Among them, although a large number of bridges did not collapse after experiencing the earthquake, due to the special location and serious damage of some components in the substructure of the bridge, as well as the backwardness of the reinforcement technology, the entire bridge had to be demolished and rebuilt, causing huge damage. Material waste and economic losses have also greatly affe...

AI Technical Summary

Problems solved by technology

The existing three types of reinforcement schemes each have their own insurmountable shortcomings: the lack of strength and toughness of ordinary concrete, the corrosion of steel casings in the external environment, and the problem of hollowing out of concrete and steel due to shrinkage and creep effects, carbon fiber The high-strength characteristics of the steel bar only come into play after the tensile steel bar yields, the strength utilization rate is not high, and the reinforcement effect is not significant

The use of ordinary concrete reinforcement has a long construction period, a large increase in the cross-sectional size of the components, and poor seismic performance of the reinforced pier, etc.

The existing main solution to these problems is to increase the thickness of the reinforcement layer. However, this method of improving the working condition of the reinforcement part by increasing the structural size can have a certain effect, but the excessively high strength cannot guarantee the provision of the plastic hinge area section. Design expected plastic rotational capacity, resulting in capacity-protective members prior to ductile member failure

In addition, the ductility of the bridge pier will deteriorate after the traditional method is strengthened, and the position of the plastic hinge will shift. It may even happen that the bridge pier will no longer be a ductile energy-dissipating component when the next earthquake occurs, and the plastic hinge will appear in the position that is difficult to repair, such as the pile foundation.

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