| 摘要 |
The present invention provides a method of producing a concrete pipe including the steps of immersing a tendon in a concrete pour mould forming a pipe, the mould having at least one longitudinal divider so that the cast pipe is longitudinally split, expanding the pipe radially outwardly to cause circumferential movement between the tendon and concrete to thereby stress the tendon, filling the split with a filler to form a stressed cylinder, the improvement comprising the steps of applying an enclosing sheath means to said tendon, applying an antifriction layer to the internal surface of said enclosing sheath means or to the tendon, said enclosing sheath means forming a non-rupturable pressure surface between the tendon and cured concrete. The present invention also desirably provides a method of enclosing a tendon which is stressed and destined to be wrapped in tension around a concrete pipe comprising the steps of tensioning the tendon sufficiently to stress the pipe when thereon, applying an enclosing means to said tendon to seal the tendon from outside environment wrapping said tendon around said concrete pipe, maintaining said tendon in stressed condition. |
