The mechanical and frost resistance properties of pressed concrete blocks mixed with the polymeric aluminum chloride waste residue

Abstract

This study aims to research on the mechanical and frost resistance properties of pressed concrete blocks mixed with the polymeric aluminum chloride (PAC) waste residue. Experimental studies on the activity index of volcanic ash, mechanical property, frost resistance and microstructure of pressed concrete blocks mixed with PAC waste residue were carried out. The results show that the activity index of volcanic ash of PAC waste residue reaches 74.96% at a particle size of 0.075 mm or less and a curing age of 28 days. Based on results of mechanical property tests, the optimum dosage of PAC waste residue is 15%, at which time the compressive and bending strength only decreases by 14.57% and 15.84%. Based on results of frost resistance tests, the optimum dosage of PAC waste residue for pressed concrete blocks is 10%. After 50 freeze–thaw cycles, when the dosage of PAC waste residue is 10%, the strength loss rate is only 3.04%. XRD and SEM tests show that PAC waste residue participates in chemical reactions. With a small amount of PAC waste residue, the structure of the specimen remains dense and therefore the strength decreases less.