Water-Pressure Synergy Mechanisms of Pressure-Driven Geopolymer Granulation of Solid Waste

Abstract

Using solid waste to produce artificial aggregate (AA) to replace natural aggregate has attracted extensive research interest. This study proposes pressure granulation under minor water to produce AA. The strength formation and water-pressure synergy mechanisms are discussed by setting water and load configurations and characterizing the internal pore structure. In addition, the water damage to the AA is discussed. The results show that the squeeze-out effect caused by the synergistic effect of water and load determines AA’s physical and mechanical properties. Furthermore, the law of the squeeze-out effect is proven by the fact that the AA with a compressive strength of 19.77 MPa was obtained under a 10% water-to-powder ratio and a 55 kN load. In addition, water erosion severely affects AA’s strength, which might be relieved by decreasing the water absorption of AA.