| 摘要 |
<p>PURPOSE: To detect breakage and leakage of water in a water-shielding sheet by mixing conductive fibrous material whose electrical resistivity is at most a specified value into fiber cloth for reinforcement and coating both sides of the fiber cloth for reinforcement with resin, and attaching terminals for checking continuity of conductive fiber to the fiber. CONSTITUTION: A water-shielding sheet is constituted by interweaving conductive fibrous material 1 of electrical resistivity <=2×10<-7>Ω.m with fiber cloth for reinforcement and coating both sides of the fiber cloth for reinforcement with a resin. Terminals 2 for checking continuity of the conductive fibrous material 1 are attached thereto in the water-shielding sheet. Breakage or leakage of water in the water-shielding sheet is detected by checking continuity of the conductive fibrous material 1. At this time, when electrical resistivity is high, the current hardly flows, and recognition of continuity is made difficult. For example, metals such as gold, aluminum, nickel and iron or alloy of copper and silver are preferable substance for forming the conductive fibrous material. Furthermore, elongation in rupture of conductive fiber is preferably larger than fiber for reinforcement excepting conductive fiber and smaller than the elongation in rupture of the water-shielding sheet.</p> |
