Why doesn't cement fall off the wall?

Corresponding to this, it is air-hardening or non-hydraulic cementing materials, such as lime, gypsum, magnesium oxychloride cement and so on. After mixing with water, these cementitious materials need to be cured and hardened in the air, and the humidity in the air should not be too high, otherwise the hydration products will be dissolved or transformed, and the strength or strength reduction will not occur after wetting. Cement is hydraulic because ettringite and calcium silicate gel, the main reaction products of cement hydration, are insoluble in water, while calcium hydroxide is slightly soluble in water. With the hydration reaction, the strength gradually develops. The water in the surrounding environment will not damage the strength development. It has nothing to do with colloid. Portland cement, lime, gypsum, magnesium chloride, etc. They are all powdery inorganic mineral materials, which have strong chemical activity with water and form a whole with certain strength after solidification. Calcium silicate, the main hydration product of portland cement, is called' gel', which belongs to inorganic polymer, has very high hardness, is insoluble in water and resistant to various chemical corrosion, and is the main dependence of the strength and corrosion resistance of hardened cement paste. Cement used in underwater construction is generally ordinary cement, including aggregate and sand. It's just that a kind of concrete admixture called flocculant is mixed in it, which can greatly improve the viscosity of concrete and is not easy to separate and disperse when pouring in water. Cement Cai Ying. Com to recommend the answer for you.