Abstract
In the initial stage of mixing for ultra high-strength concrete, the fine particles of silica and cement contact with water to generate cement balls which deteriorate the concrete quality. Crushing was difficult with conventional mixers, but the manufacturing system with a static mixer which developed, impresses an enormous shearing force on the cement paste to crush the cement balls into uniform particles. So compared with the conventional batch system, the consistency of the concrete is improved, the compressive strength of the concrete is increased by over 10% and the strength disparity decreased to about one-fifth to enable the manufacture of quality ultra high-strength concrete reliably.
