Application for free probation, counselling telephone: 400-8352-114
The swelling agent is an additive that allows concrete to generate a certain volume of expansion。
The types of expansion agents are calcium sulphate, calcium oxide, magnesium oxide, metal, etc。
1. Common inflation
(1) calcium sulphate. The main components are penthouse and water-free plaster or dihydrate; csa expansion (mainly calcium sulphate-free); and u type expansion (u) the main components are calcium aluminides without water, amphibians, plaster, etc。
(2) calcium oxide inflators, which are prepared in a variety of ways, such as by adding an appropriate amount of plaster with a low temperature of lime and aqueous slag to a certain temperature; by mixing lime with hard fat acid; and by mixing limestone, clay, plaster with a certain temperature to burn mature powder with a certain temperature。
(3) metal-like inflation
The commonly used iron crumbs are made of iron powdered oxidizers (e. G. Perchromate, permanganate, etc.)。
2. Activation mechanisms for expansion agents
The composition of the various agents mentioned above varies, as does the cause of the expansion. When calcium sulphate is added to cement concrete, the self-constructed calcium hydrosulphate hydrohydrate or is involved in the wateration of the cement mineral or reacts with the cement water chemical to form calcium trisulphurized aluminides (sulfonite), which is produced in a manner that increases the solid phase significantly and causes surface volume expansion. The expansion of calcium oxides is due mainly to calcium oxide crystal water, which forms calcium hydroxide crystals and increases in volume. Iron powder expansion is the result of the oxidation of metal metal and oxidizers in iron powder, the formation of iron oxide and the generation of rubber-like iron hydroxide in the alkaline environment of cement hydrosis。
Inflated concrete (slurry) from calcium sulphate aluminides shall not be used for long-term work at ambient temperatures above 80°c. Concretes of calcium sulphate or calcium oxide expansion are not suitable for chlorine salt additives. The filling of iron crumbs with inflating slurry shall not be used for works with diffuse currents and in areas exposed to aluminium magnesium material。
