| 摘要 |
PURPOSE: To apply the same compressive stress as that of the usual prestressing method to all parts of a product by adding fiber whose shape and size can be developed under the transfer of thermal energy to concrete mixtures at random and executing casting, removing, curing, and thermal treatment. CONSTITUTION: As a fiber, shape memory alloy fiber or heat contraction fiber is available. It is preferable that the fiber is of very flat and thin shape, and 1 to 10 cm in length. When the shape memory alloy fiver is used, the original shape compresses concrete. As this shape, a contracted, curved, and slightly spiral shape is preferred compared to an almost or complete straight shape as an intermediate shape. When the heat contraction fiber is used, a sufficiently curved shape can apply compressive stress to concrete when the fiber is contracted. After concrete products are cured, a heat treatment should be performed at a temperature where the fiber is returned to the original shape. This concrete is suitable for radioactive waste storage containers. |
