[Video] How much does expanded, water-absorbing perlite weigh?

Perlite is a common building material. After fine grinding and ultra-fine grinding, perlite raw sand can be used as filler in rubber and plastic products, pigments, paints, inks, synthetic glass, thermal insulation bakelite and some mechanical components and equipment. It is slightly denser than water and is itself hollow, like a sponge. High temperature firing will expand 4 to 30 times, the more expansion, the stronger water absorption capacity, perlite bulk water absorption rate can reach 250% -750%. The water absorption rate of the perlite for construction can be controlled within 90% after being treated by a hydrophobic process, the dead weight of the expanded perlite bulk material without hydrophobic treatment can reach 3-9 times of the original dead weight under extreme conditions, and the weight of each cubic meter of perlite after water absorption and expansion may exceed one ton. The roof of the gymnasium does not have a large number of load-bearing as its main function. Perlite has been placed for a long time. After the continuous heavy rain in summer, the risk of collapse has greatly increased.