Low-temperature concrete early strength agent

Abstract

The invention relates to a low-temperature concrete early strength agent, which belongs to cement additives. The early strength agent consists of sodium metaaluminate, sodium silicate, sodium sulfate, sodium carbonate, lithium carbonate, lithium bromide, alkali metal chlorides, alkali metal hydroxides, zinc fluosilicate, magnesium fluosilicate, sodium fluosilicate, calcium fluoride, triisopropanolamine, a filtrate reducer, beta-naphthalene formaldehyde sulfonate polycondensate, ultrafine powder SiO2, ultrafine powder Al2O3, ultrafine powder Fe2O3, ultrafine powder CaO and ultrafine powder MgO. The early strength agent is mainly applied to winter concrete construction or low-temperature environmental emergency projects; when the early strength agent is used, the composition mixture is added into concrete according to 2 to 5 percent of the total weight of cement, water is added and then stirring is performed; and a cement block with the strength of 13.5MPa can be formed in a low-temperature environment at the ambient temperature of approximately 4 DEG C within 12 hours, a cement block with the strength of 18.5MPa can be formed within 24 hours and a cement block with the high strength of 30MPa can be formed within three days.

Description

technical field [0001] The invention relates to a cement external admixture, in particular to a low-temperature concrete early-strength agent used in winter concrete construction or low-temperature environment emergency engineering. Background technique [0002] Generally speaking, concrete engineering accounts for about half of the entire civil engineering, so the hardening speed of concrete plays a very important role in shortening the construction period of civil engineering. At present, there are many external admixtures used in China to improve the early strength of concrete at 10°C to 40°C, such as cement-water glass slurry early strength agent, which has a short setting time and a high setting rate. Over the years, it has been widely used in soft soil reinforcement, well wall grouting, water seepage accident treatment, etc., and solved many key problems. However, cement-water glass slurry has the problems of low low-temperature strength and poor durability of concret...

AI Technical Summary

Problems solved by technology

However, for some special occasions such as highways, high-speed railways, emergency repairs of reservoirs and dams, and rapid winter construction of military projects; for example, for the damaged subgrade and pavement of winter highways, the requirement of restoring the passage of heavy transport vehicles in a short time for emergency repairs, on-site pre-production Requirements for fast closing and early strength of concrete pouring at component closures, requirements for rapid early strength in winter for facilities such as high-strength shock wave-resistant military dikes, and rapid repairs in winter for projects such as rapid repair of reservoirs and dams. At present, there is no such early strength of low-temperature concrete The agent can meet the performance that the compressive strength of the poured concrete can reach more than 10Mpa within 12 hours in winter

Images