| 摘要 |
PROBLEM TO BE SOLVED: To increase the introduced pre-stress, and avoid the inconvenience by the large rigidity of a PC strand by solving a problem that a core wire slips when using the PC strand of a three-layer structure in the pre-stress introducing method by the pre-tension system. SOLUTION: In introducing the pre-stress in the concrete by the pre-tension system using the PC strand A of the three-layer structure comprising the core wire 1 formed of a center wire 1a and a second layer wire 1b and a side wire 2, the center wire, the second layer wire and the side wire are formed PC steel strands, and the slip of the core wire is prevented by calculating the design- introduced pre-stress considering the reduction in the pre-stress attributable to the slip of the core wire, and forming the center wire, the second layer wire and the side wire of an indented wire of PC steel.
|
