Ultra-high performance concrete based on composite cementing material system

Abstract

The invention discloses ultra-high performance concrete based on a composite cementing material system. The ultra-high performance concrete is prepared from a composite cementing material, quartz sand, Guami stone, steel fiber, a water reducing agent and water, the composite cementing material is prepared by compounding cement, fly ash beads, silica fume and mineral powder, and the molar ratio of chemical components in the composite cementing material comprises that the ratio of SiO2 to Al2O3 is 6.4-8.3; the ratio of SiO2 to Na2O is 121.4 to 203.8; the ratio of SiO2 to CaO is 0.9 to 1.1; and the ratio of SiO2 to SO3 is 82.2 to 281.7. The composite cementing material system is used for preparing the ultra-high performance concrete, the compressive strength ranges from 26.97 MPa to 139.8 MPa, the breaking strength ranges from 6.4 MPa to 20.27 MPa, and the fluidity ranges from 144.5 mm to 162.5 mm. Through organic combination of different types of cementing materials, rapid hardening and early strength of the ultra-high performance concrete are achieved, the performance of the ultra-high performance concrete is improved, and carbon emission is reduced; and the prepared ultra-high performance concrete has the advantages of rapid hardening, early strength, high toughness, high impact resistance, high durability and the like, is suitable for rapid repair and replacement of bridge expansion joint transition areas and other concrete members, and has good popularization and application prospects.

Description

technical field [0001] The invention relates to the technical field of building materials, in particular to an ultra-high performance concrete based on a composite cementitious material system. Background technique [0002] In the highway bridge structure, the expansion joint device is an auxiliary facility for the bridge to meet the deformation requirements of the bridge deck. It is usually installed between two girder ends, between the girder end and the abutment, or at the hinge position of the bridge, but its construction quality is often determined by related projects. ignored by technicians. With the rapid development of traffic, the traffic volume has increased sharply, and some vehicles are overloaded vehicles and heavy vehicles. Expansion devices of highway bridges are directly subjected to the repeated action of traffic loads. Many highway bridges have experienced expansion joint diseases, and expansion joint devices have become vulnerable and frequently repaired ...

AI Technical Summary

Problems solved by technology

In recent years, relevant scholars have proposed to use ultra-high performance concrete in the transition zone of bridge expansion joints, but there are some disadvantages. For example, the raw material Portland cement used in the authorized announcement number CN110627439B is of a single type and cannot be well based on actual engineering. The deployment design is carried out according to the actual situation; the raw materials used are water-based epoxy resin emulsion and organic-inorganic hybrid fiber, which not only increase the difficulty of construction, but also increase the time for concrete preparation and slow down the progress of the project. Moreover, the invention is only used in the bridge expansion joint transition area. no promotional value

Also as authorized announcement number CN108046658B in the implementation process, need to prepare A, B, C three kinds of components, not only its preparation process is complicated, its cost is high, and this invention is only applicable to bridge expansion joint transition area, is not conducive to the actual promotion application

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