Acoustic Materials Based on Expanded Obsidian

Abstract

Increasing attention is paid to noise control and provision of the required acoustic comfort. This is due to an increase in the noise of the environment, the concentration of people in the cities, development of industry, transport and aviation. Currently, mass construction does not have the necessary number of sound-proof products and this demand is constantly increasing. Therefore, the development of new efficient sound-proof products, especially on the base of industrial waste, is of particular importance. While separating obsidian during the production of rubble and sand from lithoid pumice and perlite - it turns into a waste product. With the expansion of obsidian with grain sizes from 5 to 20 mm in a duration of 3-10 minutes at temperatures from 1050 to 11500С, it is possible to obtain a lightweight porous material with the lowest average density of 200–350 kg/m3 (in a piece of stone) and thereby solve environmental issues - to recycle production wastes. The requirements for mechanical strength and decorativeness of sound-absorbing materials are increased, since they are used for tiling internal walls, so they must have low water absorption capacity, low hygroscopicity, and be fire and bio resistant. On the base of expanded obsidian, it is possible to obtain acoustic materials: cellular concrete and plasters with cement and gypsum with an average bending strength of 2.229 and 5.679, and 6.2095 and 12.670 MPa for compression.