Reinforcement of Ordinary Concrete Waterway Tunnel Lining for Long Life
The reinforcement method for waterway tunnels is sheets of carbon fiber-reinforced strands glued with resin, which is suitable for the wet environment of waterway tunnels, the lining of which is prone to flexural cracking by aging degradation. This method was jointly developed with the Nippon Steel Chemical & Material Co., Ltd., and given the Award for Excellence of the Fourth Infrastructure Maintenance Awards.
Tunnel wall before and after reinforcement
Composition of reinforcement materials
Reinforcement work process
Features
- Good workability
The application of carbon fiber-reinforced sheets is a simple work process that requires less labor and no heavy equipment. The carbon fiber-reinforced stranded sheets and epoxy resin are cured in the factory before being transported to the work site. - Excellent adhesiveness in wet environments
The applied primer has excellent adhesiveness to wet surfaces. - Low roughness coefficient
The roughness coefficient is 0104, as measured by the Research Center for Agricultural Information Technology of the National Agriculture and Food Research Organization. - Long abrasion durability
The water and sand jet wear test obtained a value of 32 mm/40 years (comparison against standard specimen of mortar: 0.07), as measured by Shimane University. - Safety for quality of water
The process meets Japan Water Work Association standard JWWA K143 (qualified as an epoxy resin coating suitable for a concrete city water tank). - Permeable anchor with check valve The valve provides smooth water discharge to prevent blistering and detachment of the reinforced layer by water pressure from behind the seal.
