New Design Concept for Bridge Restrainers with Rubber Cushion Considering Dynamic Action: A Preliminary Study

• Published in: Applied sciences Vol. 10; no. 19; p. 6847
• Main Authors: Tamai, Hiroki, Lu, Chi, Yuki, Yoichi
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.10.2020
• Subjects: Algorithms; Bridge failure; bridge restrainer; Bridges; Bridges, Cable-stayed; Case studies; cushion effect; Cushioning; Cushions; design concept; Design specifications; Design techniques; dynamic finite element analysis; Dynamic response; Earthquake engineering; Earthquakes; Energy absorption; Equipment and supplies; Genetic algorithms; Load; Methods; optimization design; Retrofitting; Rubber; Safety and security measures; Safety systems; Seismic activity; Seismic design; Seismic engineering; Seismic response; simple genetic algorithm; Specifications; Structural optimization; Superstructures; Urban areas; Japan
• ISSN: 2076-3417; 2076-3417
• DOI: 10.3390/app10196847

A bridge unseating prevention system is a safety system for bridge collapses caused by large earthquakes, beyond the assumption of aseismic design specifications. Presently, the system is generally adopted for newly constructed bridges and the seismic retrofitting of existing bridges. Cable type bridge restrainers are included in the system, and they are expected to prevent superstructures from exceeding the seat length of substructures. Although the bridge restrainer works during an earthquake, it is designed to be static in the current design. In addition, although the constituent elements of bridge restrainers include a rubber cushion to absorb energy during an earthquake, the effect is not included in the design. Thus, the current design lacks the dynamic effects of earthquakes and the cushioning effect of the rubber. Furthermore, in the case of a multi-span bridge, there is no particular decision as to where the restrainers should be placed or what kind of specifications they should have. Therefore, in this paper, a new design concept that considers the dynamic action of the earthquake and the cushioning effect of the rubber is proposed by coupling dynamic response analysis using a frame finite element (FE) model and a simple genetic algorithm (SGA).