Estimation of Sediment Discharge Controlled by Sediment-filled Check-dam in a Forested Catchment
2016
Seo, J.I., Kongju National University, Yesan, Republic of Korea | Chun, K.W., Kangwon National University, Chuncheon, Republic of Korea | Song, D.G., Baekrim Co., Ltd., Incheon, Republic of Korea
To estimate the sediment discharge controlled by sediment-filled check-dam and thereby enhancing factor for check-dam design and dredging criteria, we surveyed slope failures and stream-bed fluctuation caused by geomorphic disturbances (i.e., landslides and debris flows) in Inje, Gangwondo. In general, check-dams play roles for restraining and controlling sediment discharge within a section under the design equilibrium gradient and a section under the design flood gradient, respectively. The results in this study showed same pattern: that is, the closed type check-dam, which has a design restraint sediment discharge of 2,111 m³, estimated to control a sediment discharge of 3,996 m3 in the stream section within 250 m right upper area immediately after the disturbances occurred in 2006. As a result, a design control sediment discharge of the check-dam was larger than its design restraint sediment discharge. This represents that the check-dam is still having an own function for controlling sediment discharge although it exceeded the designed capacity by the sediment discharged from upstream during the disturbances. Our finding suggests that the sediment discharge controlling of check-dam may need to be evaluated separately from its sediment discharge restraint. Currently, the country, however, does not consider the design control (or restraint) sediment discharges, based on the actual field survey, as criteria for checkdam design and/or dredging work. Therefore, the accumulation of the quantitative data is required to support that check-dam has functions for both restraining and controlling sediment discharge. This would be a way to develop our erosion control technology to the scientific technology equipped with a more objective and systematic aspects.
显示更多 [+] 显示较少 [-]