Densified Powder&Grain Microsilica Bulk Density:550-700kgs/m3 Microsilica. silica fume concrete in the application1,Manufacture high-strength concrete (C70 above), significantly enhanced the strength of concrete and pumping performance; 2,Manufacture of high permeability (≥ P30), waterproof concrete structure for the MTR, tunnels, the basement of high-rise buildings; 3,Manufacture marine and ...