PURPOSE: To simply contrive to improve and strengthen long lasting and stabilized soil bearing load without developing honeycomb and to progress construction without causing environmental pollution and to complete the construction through excellent soil gushing by agitation at low cost by a method wherein cement is contrived to be turned to particle-free state by circulation system by being sent through a sand pump and a return pipe back to a middle mixer-crusher.

CONSTITUTION: To an upper mixer-crusher 4 of a cement crusher 1, hot water is poured by means of a hot water feeder or cement is charged. Cement paste is formed through a series of rotary operation of a main structure consisting of a rotating shaft 2, a worm gear 3 and an agitating shaft 8 by a motor so as to accelerate the semi-forcible dissolution and grinding of the cement paste in combination with rubbing-in action. After that, the resultant cement paste is let fall through a cock 9 into a mixer-crusher 10 so as to further grind past particles developed by false store relief beams to particle-free state with re-rubbing-in and crushing action. After that, the resultant cement paste is let fall through a cock 20 into a mixer-crusher 21 so as to realize particle-free state thrice with rubbing, crushing and brightening action. By sending back the resultant cement paste through a sand pump 29 and a return pipe 30 to the mixer-crusher 10 so as to avoid the wakening of action by assisting addition, the realization of particle-free state by repeated grinding and sublimation action is contrived by simple specified circulation system.