Investigation of unfired Bricks Prepared by Shangluo Molybdenum tailings

Using molybdenum tailings in Shangluo as a core sample and the cement as gelled material, the unfired brick is prepared by mixing molybdenum tailings, cement, sand, silica powder and accelerating admixture, and then stirring and vibration. The effects of molybdenum tailings content, the ratio of molybdenum tailings to river sand and the addition of the silica powder on mechanical properties of the unfired brick. Results show that With the addition of molybdenum tailings increased, the mechanical properties of the unfired brick was decreased. When the addition of molybdenum tailings is below 75%, the flexural strength and compressive strengh are above 4.83MPa and 15.69MPa respectively, it meets MU15 standard. With the ratio molybdenum tailings to river sand increasing, the mechanical properties decreased firstly, and then increased. The mechanical properties of unfired brick is decreased with increasing of the silica powder.