Numerical Simulations of Local Scour at Samsan Bridge Piers in Korea.

Lee, J.; Park, S.-K., and Hong, S., 2017. Numerical simulations of local scour at Samsan Bridge piers in Korea. In: Lee, J.L.; Griffiths, T.; Lotan, A.; Suh, K.-S., and Lee, J. (eds.), The 2nd International Water Safety Symposium. Journal of Coastal Research, Special Issue No. 79, pp. 154-158. Coconut Creek (Florida), ISSN 0749-0208. The Samsan Bridge connects Ganghwa Island and Incheon in the mid-western region of South Korea. The country is making an effort to improve access to the island from its major cities, and the construction of the bridge is part of that process. External factors such as wind waves, tide currents, currents, and scour depths around piers should be considered in the construction of a bridge. In order to obtain scour depth values around bridge piers, this study conducted numerical simulations on morphological changes using the SADEM (SAnd Deposit and Erosion Model). The morphological changes were calculated by solving the conservation of sediment transport equation. A field measurement was performed at the Seokmo channel in the Han River estuary (South Korea) to verify the numerical results. A 153×210 grid system with a coarse grid size of 22.8 × 30 km was used in the SADEM. The maximum stream velocities of 10, 50, and 100-year flood return periods during the ebb tide contributes to sediment mobilization in the Seokmo channel. The maximum scour depth was calculated to be 9 m around the central bridge's pier during the flood ebb for the 100-year return period. This was due to the upstream discharge during river flooding. The results of the numerical simulations are expected to be objective indicators of optimal design, construction, and future maintenance of the Samsan Bridge. [ABSTRACT FROM AUTHOR]