| Innovative corrosion protection for concrete structures through the use of titanium plates was studied in order to establish effective and economical repair technology for such structures in sewerage facilities. The construction process of the proposed method is as follows: (1) Deteriorated concrete is removed from the structure’s surface by high-pressure water jetting, and then the surface is restored to its original state using polymer cement mortar. (2) Titanium plates are fixed onto the restored structure surface using pressure-sensitive adhesive double-coated sheet or adhesive agent. (3) Anchor bolts are placed at the edge of the titanium plates to assist fixation by adhesive. (4) Interspaces between titanium plates, outer edges of plates and circumferences of bolts are sealed using silicone sealant. Applicability of the construction method to the repair of concrete structures was evaluated based on existing quality standards for sheet lining methods. The results of adhesion strength tests, corrosion resistance tests, permeability tests, etc. clarified that titanium has very high corrosion resistance (corrosion rate: 0.001 mm/year in pH 1.0 sulfuric acid solution), pressure-sensitive adhesive double-coated sheet or adhesive agent has sufficient adhesive properties and silicone sealant has excellent liquid barrier properties. In order to collect technical knowledge about the construction of the developed titanium covering method, a trial construction was carried out in the sewerage treatment plant at the lakeside of Kasumigaura. |
