Resource Utilization of Waste Mud -- Preparation and Properties of Foamed Concrete

Abstract

The compressed and dehydrated mud was made into filter cake, and then fly ash, silica fume and cement were added to it to prepare foamed concrete with sodium α-olefin sulfonate as foaming agent. By analysing the changing characteristics of the compressive strength, apparent density, water absorption and microstructure of the foam concrete, the key mechanism of making the foam concrete was analysed in depth. The results show that mud filter cake can improve the comprehensive performance of foamed concrete. The best mix ratio is 20% of mud filter cake, 50% of cement addition, 20% of fly ash, 10% of silica fume, 0.55 of water cement ratio and 55% of foam volume. The compressive strength of foam concrete is 1.6MPa and the apparent density is 660.26kg/m3. The water absorption rate is 23.73%, which accords with China Construction Industry Standard JG / T266-2011. Proper addition of mud filter cake can improve the pore structure and cementing material matrix of foamed concrete, and enhance the strength of foamed concrete. However, too much addition will produce connected pores and cracks, and reduce compressive strength. The results can provide theoretical basis and technical reference for mud resource utilization.