Method for preparing aerated concrete by using sandstone with low silica and high sand loam

Abstract

The invention discloses a method for preparing aerated concrete by using sandstone with low silica and high sand loam. The method comprises the following steps of 1) exploitation of the sandstone; 2)dry pretreatment; 3) raw material selection; 4) fine grinding; 5) blending and mixing and stirring; 6) pouring, static standing and curing; 7) cutting; 8) autoclaved curing; and 9) inspection. Throughdry pretreatment, the sandstone is divided into two kinds of materials of different specifications, the mud content in the coarse material is low, the mud content in the fine material is high, and blending is carried out by using 15%-20% of fine sandstone and 80%-85% of coarse sandstone to guarantee the mud content of the prepared sandstone is less than or equal to 3%. The whole technological process is simple, controllable, environment-friendly and economical. Tests show that the compressive strength B06 level is 4.5 Mpa, the heat conduction coefficient is less than 0.1 W / (m.K), the dry shrinkage value is less than 0.4 mm / m, and the anti-freezing mass loss is less than 4%, the product quality meets the standard technical requirements, and the method is suitable for various building wallthermal insulation materials, and has a wide market prospect.

Description

technical field [0001] The invention belongs to the technical field of building materials, and in particular relates to a method for preparing air-entrained concrete using sandstone with low silicon dioxide and high sandy loam. Background technique [0002] The main component of clay impurities in sandstone is aluminum oxide, which has two effects on the performance of air-entrained concrete: on the one hand, because clay is a highly dispersed material with strong water absorption, when the content is too high, it will make The viscosity of the slurry increases. If the water consumption is increased to ensure a certain viscosity, the hardening time of the embryo body will be prolonged; on the other hand, the clay contains a certain amount of aluminum oxide, which can promote the formation of tobermullite. Calcium carbonate in the sand is not easy to be too much, generally not more than 10%. When the mud content in the sandstone is high, the silica content naturally decrease...

AI Technical Summary

Problems solved by technology

At present, river sand resources are scarce, and the cost of river sand and high-quality sandstone is high, usually 140-160 yuan / square