Expressway Authority of Thailand Rama IX Bridge "U-RIB"

Cooperation in The Development and Manufacture of Materials for Repairing and Strengthening Aging Bridges. Contribution to Reduction in The Burden on Workers During Construction by Realization of Lightweight and Highly Rigid Materials. 

We participated in the plan by Expressway Authority of Thailand to counteract the deterioration of the Rama IX Bridge (*1) in Bangkok, Thailand with the use of CFRP reinforcing materials. In the plan of the reinforcement work to support the deck from the inside by placing reinforcing pillars inside the upper and lower decks that make up the main girder, the reinforcing material U-RIB (top and bottom), which was developed together with a Thai construction  consulting company, demonstrated sufficient performance as the base of the pillars. A total of 1,150 pieces were delivered. The U-RIB, which is the base of the reinforcing pillars, was required to be highly rigid, but at the same time, it needed to be lightweight to reduce the burden on workers during construction and achieve safe work. The U-RIB, which is lightweight while maintaining the necessary rigidity, is achieved by using UD material as the main material in the longitudinal direction, laminating it in multiple layers, and molding it with use of the autoclave method. *1: Rama IX Bridge is a bridge over the Chao Phraya River, which flows through the western part of Bangkok, Thailand. The bridge is 781.2 m in overall length and consists of a two-tiered deck structure with main girders suspended by cables from main towers on both banks. Construction began in 1984, and it opened in 1987. It was constructed by a joint venture of five Japanese and Thai companies with the support of a yen loan.