台灣橋樑的主要災害來自於橋基受河水沖刷而造成損壞，而橋基沖刷不只是個別橋墩局部沖刷而已，而是河床整體性下降所造成的。若針對個別橋樑施作的橋基局部保護，只能達到有限的防護效果，無法根本徹底解決橋基裸露的問題。而河床沖淤除受河川水理特性、河道地形與河川質等自然因素之影響外，人類行為的影響更常是重要的因素。例如在河川上游採取砂石、在河道兩岸與水爭地、或在河道上修建水利工程、治河工程及其它工程建築物，這些人類行為的干擾將使河道沖淤變形將更為顯著。由於本省橋台、橋墩及橋基保護工之現場沖刷問題相當複雜，本計畫擬結合現場調查、實驗分析之技術，有系統地針對目前及未來本省可能發生之橋基沖刷之束縮沖刷及側向沖刷現象進行研究，並分析其防治工法，以儘速改善可能導致之橋樑安全危害問題。研究成果將可提供國內交通單位對橋台及橋墩沖刷或其它相關防治工法之設計及施作時的參考。 The major damage to bridges in Taiwan is the scouring of bridge piers and abutments. The bridge scouring problem involves the local scouring at the bridge foundation and the general draw down of the river bed. In Taiwan, the general draw down of river bed is aggravated by the sand-mining in the rivers and improper design of hydraulic structures. Therefore, any counter-measurements of the bridge scouring need to deal with these phenomena. This study plans to combine field observation and laboratory experiments to investigate the local and general scouring in details, especially on the topics of contraction scour and lateral erosion. Results of the study can enhance our understanding of the scouring mechanism, as well as the design of bridge foundation and the associated counter-measurements. 研究期間：9001 ~ 9012
