Myeongnyang Strait; however, this strait is now spanned by the South Korea's longest suspension bridge spanning 484 meters. Here in 1597 admiral Yi Sun-sin
Separating this large island from the Korean Peninsula is the Myeongnyang Strait, site of the historic battles of the past. Korea's most celebrated hero, Admiral Lee Sun-Shin, dealt crushing defeats here to the vastly superior aramada from Japan which had already occupied much of the peninsula. In 1597, using his fabled iron clad "turtle ships" and his knowledge of these treacherous waters, with the fastest tidal currents in Asia, the final victories were won.
These tides, the frequent typhoon force winds, and the long distance to be spanned presented unusual challenges for the engineers in designing the bridge, the longest suspension bridge in Korea. [the new Incheon Bridge may have surpassed it, completed just a year or two ago].
The Great Jindo Bridge had been in the conceptual stages at least since the early 1970s, but it would be another decade before the dream of connecting Korea’s third larges island to the mainland would be realized. In doing so, some history was made. There is an extensive history of the construction of this unique suspension bridge, with a brief excerpt from the opening abstract as follows:
“During the early 1980's Rendel Palmer & Tritton ( now practicing as High-Point Rendel-HPR) was responsible for the full detailed design and supervision of construction of a major cable-stayed bridge linking Jindo Island to the South West corner of the Korean Peninsular, fot the Ministry of Construction & Transportation. This bridge, with a 344m main span and 70m side spans, was not only one of the world's longest cable stayed spans at the time, but more significantly, the slenderest, being just 11m wide. As a consequence, considerable effort was expended on ensuring the aerodynamic stability of the design, both during construction and in service. The bridge was opened to traffic in 1984”.
Michael Jan King, Woo Jong Kim, and Chung Yong Cho, “Twinning of Jindo Grand Bridge, Republic of Korea,” in Current and Future Trends in Bridge Design, ed. Parag C. Das, et. al (London: Thomas Telford Publishing, 2001)
The photos in this waymark illustrate the resulting bridge with its second “twin” in place. At the time of this visit, all traffic was routed over the second bridge on the west side. It is unclear what the plans are for the original bridge which sits just a few feet lower than the second span. The abutments on each end of the second bridge are capped with a bronze statue of Admiral Lee on one side, and a reproduction of his famous “turtle ship” on the other.
It turns out that there is another unique feature to the second bridge which has been extensively reported. It is equipped with hundreds of wireless monitoring devices, measuring and transmitting data on the bridge’s condition and performance.
“The long spans and slender cables of the Jindo Bridge in South Korea are dotted with a small army of electronic sentinels tiny wireless sensors and microprocessors that monitor the bridge’s structural health. The network constantly analyzes factors like vibration, wind and humidity, and promptly reports anomalies to a computer that then passes along the news.
The Jindo Bridge network has 663 wireless sensors, each providing a channel of information. . . “
Anne Eisenberg, “Keeping Tabs on the Infrastructure, Wirelessly New York Times (March 12, 2011)
Several other interesting articles for further reading can be found in:
CSL Coordinated Systems Laboratory
“Illinois researchers have developed an inexpensive, wireless bridge monitoring system”
Structure Magazine “Wireless Monitoring of Civil Infrastructure Comes of Age”
A general reference which includes some history of Jindo and of the bridge can be found in the Wikipedia entry for Jindo Island.