Research on preparation of high-strength unfired brick by shield muck

The shield muck is classified as bulk solid waste. To enhance the high-value resource utilization of muck, a high-performance unfired brick was developed by static pressure molding with cement and slag as cementitious materials and shield muck and crushed stone as the primary raw materials. The compressive strength and durability of the unfired brick were determined through the component screening test of muck and mechanical property test. The microstructural performance was analyzed by SEM. The results show that the mechanical properties and durability of unfired brick prepared by modifying the shield muck, cement, and graded crushed stone, GGBS, and activator were obviously improved, and the microcosmic properties of unfired brick were obviously better than that of brick made by simply using cement-sludge. The 28-day compressive strength, water absorption, and post-freezing strength loss of the unfired brick with the optimum ratio were 40.1 MPa, 5.4%, and 11.5%, respectively. This research provided valuable insights into the resource utilization of similar shield muck in China.