Chemical Resistance of Autoclaved Concrete with and without Polymer Impregnation

Abstract

Cement concrete is a most popular structural material at present, but its basic weakness is a limited chemical resistance to various chemical agents.
In this paper, autoclaved concrete (AC), polystyrene-impregnated autoclaved concrete (PIAC) and water-cured concrete (WCC) were prepared and tested for chemical resistance to ten types of chemical agents such as hydrochloric acid, sulfuric acid, sodium hydroxide, etc..
The conclusions obtained are summarized as follows:
(1) In general, the chemical resistance of various concretes is in the following order; (good) PIAC>AC>WCC (bad).
(2) The aggressive chemical agents that attack markedly various concretes are hydrochloric acid, sulfuric acid, ammonium sulfate, etc..
(3) It seems that the chemical resistance of various concretes depends on the formation of free Ca(OH)₂ (highly reactive and susceptible to attack by chemical agents) and tobermorite (chemically resistant and watertight, produced as a result of autoclaving) in them.
(4) The superior chemical resistance of PIAC is due to the impregnation of autoclaved concrete with chemically resistant polymer (polystyrene).