An unreinforced steel-UHPC composite bridge deck structure and a construction method thereof

Abstract

An unreinforced steel-UHPC composite deck structure comprises a UHPC bridge deck, an orthotropic steel bridge deck and a connecting bolt, and that main part of the UHPC bridge deck is not provided with stress reinforcement and structural reinforcement. When the UHPC bridge deck is cast in-situ in sections, the joint part adopts a keytooth bite joint or a flat joint with close reinforcement, and the keytooth bite joint is matched with a metal corrugated sleeve and a joint thread steel bar. The invention also discloses a construction method of the composite bridge deck structure. This steel-UHPCcomposite bridge deck structure is simple, which significantly reduces the raw material cost of composite bridge deck structure, reduces the construction human cost, and shortens the construction period, and the overall bearing capacity and fatigue resistance of bridge deck meet the stress requirements. the unreinforced steel-UHPC composite bridge deck structure is suitable for fatigue strengthening of orthotropic steel bridge deck and rigid deck paving of new steel bridge.

Description

technical field [0001] The invention relates to an ultra-high performance concrete composite bridge structure, in particular to an unreinforced steel-UHPC composite bridge deck structure and a construction method. Background technique [0002] Ultra-high performance concrete (UHPC) is considered as one of the most innovative cement-based engineering materials due to its excellent mechanical properties. In order to comprehensively solve the two typical problems of the bridge deck asphalt concrete pavement vulnerability and steel bridge deck fatigue cracking, Chinese patents CN 201704626U and CN205046474U disclose the steel ultra-high performance concrete bridge deck structure, through the ultra-high performance concrete The steel bars are densely arranged in the layer, and the two are closely connected through the shear studs welded on the steel bridge surface, so as to reduce the self-shrinkage performance of UHPC. This composite bridge deck structure can significantly impro...

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Problems solved by technology

This composite bridge deck structure has very good mechanical properties, but its high cost hinders the development of this composite bridge deck, and the dense reinforcement method used in it requires a lot of labor costs and resource consumption, so the development It will be necessary to develop a steel-UHPC composite bridge deck with lower engineering cost

[0003] In the analysis of the autogenous shrinkage mechanism of ultra-high performance concrete inhibited by rice husk ash, it is disclosed that adding 20% ​​rice husk ash (RHA) with an average particle size of 5.6 μm can reduce the shrinkage performance of UHPC itself; and the maintenance process of UHPC layer in the composite bridge deck Generally, standard curing is performed for 36-48 hours first, and then 90°C high-temperature steam curing is carried out for 48 hours. According to existing research, UHPC after high-temperature steam curing basically does not produce shrinkage strain, so it is only necessary to pay attention to the self-shrinking performance during the standard curing period. In fact, Although the self-shrinkage performance of UHPC is relatively large, due to the self-healing ability of UHPC early cracks, its crack resistance is still good

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