High-ductility low-shrinkage anti-cracking concrete for bridge deck pavement and preparation method thereof

Abstract

The invention belongs to the field of concrete structural materials, and discloses a preparation method for high-ductility low-shrinkage anti-cracking concrete for bridge deck pavement. The high-ductility low-shrinkage anti-cracking concrete for bridge deck pavement is characterized by comprising the following components in proportion: 135-155 kg / m<3> of water, a cementing material, 600-800 kg / m<3> of fine aggregate, 950-1150 kg / m<3> of coarse aggregate, 2.0-3.0 kg / m<3> of shrinkage-reducing ductility-increasing component,10-20 kg / m<3> of internal curing agent, 3.0-5.0 kg / m<3> of water reducing agent and hybrid fiber, wherein the cementing material comprises 320-380 kg / m<3> of cement and 20-40 kg / m<3> of coal ash in proportion; and the hybrid fiber comprises 0.8-1.0 kg / m<3> of organic polymer fiber and 40-50 kg / m<3> of steel fiber in proportion. According to the concrete and the preparation method for the concrete disclosed by the invention, reinforcement meshes on the bridge deck pavement layer can be cancelled.

Description

technical field [0001] The invention belongs to the field of concrete structural materials, and in particular relates to a bridge deck concrete which cancels the pavement plan of a steel mesh bridge deck on the top surface of a concrete beam and a preparation method thereof. Background technique [0002] The structure of modern expressway bridges is complex, and the stress conditions of the bridge deck pavement are complex. The following problems are likely to exist when paving the concrete bridge deck pavement on the concrete beam: (1) The age difference between the main beam concrete and the pavement concrete The value is large, so that the shrinkage value of the concrete poured first is different from that of the concrete poured later. The shrinkage of the concrete poured first is much smaller than that of the concrete poured later. When the volume of the newly poured concrete pavement shrinks, the concrete of the main beam will have a certain constraint on it When the te...

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Problems solved by technology

[0002] The structure of modern expressway bridges is complex, and the stress conditions of the bridge deck pavement are complex. The following problems are likely to exist when paving the concrete bridge deck pavement on the concrete beam: (1) The age difference between the main beam concrete and the pavement concrete The value is large, so that the shrinkage value of the concrete poured first is different from that of the concrete poured later. The shrinkage of the concrete poured first is much smaller than that of the concrete poured later. When the volume of the newly poured concrete pavement shrinks, the concrete of the main beam will have a certain constraint on it When the tensile stress value is greater than the tensile strength of the pavement concrete, the concrete will crack

(3) During the concrete pouring construction of the bridge deck pavement, the welding points of the steel mesh in the bridge deck pavement are easy to fall off or be stepped on, and the top surface of the bridge girder is uneven, so that the steel mesh is close to the top surface of the beam body, and the steel bars The net cannot play the role of improving crack resistance and fatigue resistance, thus weakening its contribution to the mechanical properties of bridge deck pavement

At present, the prepared bridge concrete scheme is mainly to add fly ash, mineral powder, silica powder and other mineral admixtures and high-efficiency water reducers. Mineral admixtures improve the compactness of concrete, thereby improving the ability to resist chloride ion penetration; however However, the toughness of concrete prepared by adding mineral powder, fly ash and other admixtures is still not well improved

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