| 摘要 |
PURPOSE:To provide simple and easy operation for re-application of prestress by inserting a prestressing material in tensed condition in a specific number of sheaths and by leaving the other sheaths unstressed for application of prestress afterward. CONSTITUTION:PC wires 9 as prestressing material are inserted in every other circumferentially running sheaths 8' and are tensed and filled with mortar. The other sheaths 8' are left empty. PC rods 10 are inserted in all vertically running sheaths 8, where the bottoms of the rods 10 are fixed, and half of these sheaths 8 are left unfilled. Even through the prestress is loosened by heating, reapplication thereof is obtained by inserting PC wires 9 in the circumferential unfilled sheaths 8' and filling the vertical non-prestressed PC wires 10 with mortar. |
