彎道堤防基腳沖刷防災物聯網－以大安溪水尾堤防為例

INTERNET OF THINGS FOR BEND SCOUR DISASTER WARNING SYSTEM - A CASE STUDY NEAR SHUIWEI EMBANKMENT IN DAANN RIVER

蘇志強(Chih-Chiang Su) ； 洪健豪(Jian-Hao Hong) ； 楊翰宗(Han-Chung Yang) ； 郭文達(Wen-Dar Guo) ； 王豪偉(Hao-Wei Wang)

《中國土木水利工程學刊》 31卷4期 (2019/06) Pp. 301-314

https://doi.org/10.6652/JoCICHE.201906_31(4).0002

摘要

台灣間歇性河川陡坡卵礫石彎道河段，單場或連續洪水上漲過程，河道屬非平衡輸砂，常發生急遽短期一般沖刷，並加促斜向流於堤防基腳總沖刷而掏毀堤防。本文於大安溪水尾堤防，採用無線追蹤粒子及壓力式水位計建置彎道沖刷與水理動態監測防災物聯網。2017年尼莎颱風測站洪峰流量2,649 m^3/s約Q_2洪水，由沖刷出9顆漂浮裝置，動態監測彎道縱向及橫向沖刷、平均表面流速、沖刷水深與臨界沖刷剪應力，得知堤基最大沖刷深度2.24m發生於退水段，河道沖刷率介於0.73至5.3 m/h，驗證本文提出之物聯網，適用台灣湍流河道急遽沖刷防災預警之實務應用。

關鍵字

沖刷 ； 無線追蹤粒子 ； 動態沖刷監測 ； IoT物聯網

並列摘要

Extreme short-term general scour frequently occurs during a single or several closely-spaced floods in the gravel reaches of intermittent rivers in Taiwan. For the nonequilibrium sediment-transport conditions due to the rapidly-varied unsteady flow, embankment scour along a river bend often is enhanced caused by the channelizing processes. In this study, the real-time monitoring IoT (internet of things) system using both wireless tracer scour float-out device and pressure sensor was proposed and installed at the Shuiwei Embankment in the Daann River in the central Taiwan. Total nine float-out devices were instantly monitored to measure the longitudinal and lateral bend scouring data during Typhoon Nesat-induced flood with peak flow 2,649 m^3/s (about Q_2) in 2017. In addition, the flow data, including of water surface velocity, scoured flow depth and critical flow condition of riverbed scour, were also monitored. The real-time monitor results show that the maximum bend scour depth was 2.24 m occurring at the falling limb of the flood, and the riverbed scour rates were ranging from 0.73 to 5.3 m/h. The IoT system proposed in this study can be verified as a smart and useful tool of the flood disaster warning for extreme scour potential river reaches in the steep Taiwanese rivers.

並列關鍵字

scour ； wireless tracer ； real-time scour monitoring ； IoT (internet of things)

參考文獻

水規所(2008).大甲溪河段輸砂特性試驗研究(1/3)-(3/3).經濟部水利署水利規劃試驗所委託研究報告.(經濟部水利署水利規劃試驗所委託研究報告).,未出版國立中興大學.

Hong, J. H.,Chiew, Y. M.,Lu, J. Y.,Lai, J. S.,Lin, Y. B.(2012).Houfeng bridge failure in Taiwan.Journal of Hydraulic Engineering, ASCE.138(2),186-198.

Su, C. C.,Lu, J. Y.(2016).Comparison of sediment load and riverbed scour during floods for gravel-bed and sand-bed reaches of intermittent rivers: case study.Journal of Hydraulic Engineering, ASCE.142(5)

Su, C. C.,Lu, J. Y.(2013).Measurements and prediction of typhoon-induced short-term general scours in intermittent rivers.Natural Hazards.66(2),671-687.

Melville, B. W.,Coleman, S. E.(2000).Bridge Scour.Highlands Ranch, Colorado:Water Resources Publications.