抄録
The flow condition and pumping pressure in pipeline leave a large room for investigation concerning to concrete pump in spite of its wide use. The theoretical study on the rheological properties of fresh concrete was carried out with aid of experiments using viscometer. The conclusions are as follows : (1) The fresh concrete can be regarded as Bingham's body which has a yield point of δ and a plastic viscosity ofηp1. (2) The fresh concrete flows in the pipe forming a solid plug which has a cross section equal to that of the pipe. (3) The frictional stress between the solid plug and the inner surface of the pipe is expressed as a function of the velocity of the solid plug. (4) From the results mentioned above, equations were obtained which express the pressure and pressure loss in straight pipe, bent tapered pipe.