| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a manufacturing method of a centrifugally formed concrete pipe, which has an easy finishing process and also can produce a pipe having an increased external pressure strength, and a concrete pipe produced by the method. <P>SOLUTION: The manufacturing method of the centrifugally formed concrete pipe comprises a step of centrifugally forming an outer layer of the centrifugally formed concrete pipe, a step of centrifugally forming an inner layer of the concrete pipe using a centrifugal forming finishing material containing 100 parts of a bonding agent consisting of 20-80 parts of a slag and 80-20 parts of an alumina cement and 50-300 parts of fine aggregates, and a step of heat-curing at 50-90°C. The invention provides the manufacturing method in which a heat curing time is 1-8 hours, the manufacturing method in which a thickness of the inner layer is from 2 mm to 30% of the pipe thickness, the manufacturing method in which, in the centrifugal forming of the inner layer, after the rotation at a G-force of G2.5, the centrifugal forming is carried out at G20-40, the manufacturing method in which the time of centrifugal-forming at G20-40 is 5-15 minutes, and a centrifugally formed concrete pipe manufactured by the manufacturing method of a centrifugally formed concrete pipe. <P>COPYRIGHT: (C)2008,JPO&INPIT</p> |
