Low-viscosity high-durability rapid curing duct piece concrete suitable for machine plastering

Abstract

The invention discloses low-viscosity high-durability rapid curing duct piece concrete suitable for machine plastering. Each square of concrete comprises the following components by mass: 250-350kg ofcement, 40-120kg of mineral powder, 60-120kg of fly ash, 670-700kg of fine aggregate, 1050-1150kg of coarse aggregate, and a water reducing agent accounting for 0.5%-1% of the mass of a cementing material; the water-binder ratio is 0.31-0.36; the concrete is subjected to early steam curing at the temperature of 35 DEG C or above; the 12-hour steam curing strength is larger than 50% of the 28-daystandard curing strength; the 3-day steam curing strength is larger than 80% of the 28-day strength; the inverted cone time of the prepared slump cone is shorter than 10 s, the impermeability grade islarger than or equal to P12, freeze-thaw cycles are 500 times, the electric flux is lower than 1200c, and flexural strength is larger than 9MPa. The concrete prepared by the invention can effectivelyimprove the segment production efficiency. After the working performance of the concrete is improved, a trowelling robot is introduced for trowelling work, and therefore, the mechanization degree isgreatly improved, and the concrete plays a very important role in promoting building industrialization.

Description

technical field [0001] The invention belongs to the field of shield segment concrete materials, and in particular relates to a low-viscosity, high-durability, fast-maintenance segment concrete suitable for machine plastering and an application thereof. Background technique [0002] With the rapid development of my country's urban subway construction in recent years, the subway shield tunnel lining segment is an indispensable structural component in the subway construction, and the demand for the segment is huge and the quality requirement is high. At present, the relatively advanced segment production is assembly line production, which can meet the progress of subway construction. However, in the production process of the assembly line, manual plastering is still used, the degree of mechanization is not high, the strength of the concrete plastering is high, and the segment forming and curing time is too long, which affects the progress of segment production. The use of mach...

AI Technical Summary

Problems solved by technology

However, in the production process of the assembly line, manual plastering is still used, the degree of mechanization is not high, the concrete plastering strength is high, and the segment forming and maintenance time is too long, which affects the progress of segment production

The use of machine plastering has strict requirements on the viscosity and durability of concrete, and the existing concrete cannot meet the requirements of machine plastering

Images