圖書典藏及影音數位平台

秀姑巒溪流域位於台灣東部，地跨花蓮、台東兩縣。其北接花蓮溪流域，南與卑南溪流域相鄰，主流秀姑巒溪發源於中央山脈崙天山南麓，東流入台東縱谷後，受海岸山脈阻擋，乃沿縱谷平原向北流，在匯納兩岸諸水後，於瑞穗鄉舞鶴山前再折轉向東流，並以其巨大侵蝕力橫切海岸山脈，而在豐濱鄉大港口附近流入太平洋。流域行政區域包括台東縣之海端、池上與花蓮縣之富里、卓溪、玉里、瑞穗、萬榮及豐濱等八鄉鎮。本溪流域為台東縱谷平原三大水系之一，流域面積1,790.46平方公里，其在花蓮縣部份，占全縣面積三分之一強，居住人口約十萬人，占縣人口三分之一弱，主流全長81.15公里，為全台21條中央管河川之一。主要支流有五條由南至北依序為：樂樂溪、卓溪、豐坪溪、紅葉溪及富源溪。 秀姑巒溪現況防洪構造物多屬老舊堤防，為能尋求有效維修與補強方案，擬藉由安全性評估計畫來全面檢視秀姑巒溪堤防之安全，以利後續維護管理。 本計畫主要目的為暸解秀姑巒溪堤防結構現況，先以人員目視進行檢查並提出期初報告，後續採用非破壞檢測方式如透地雷達探測、震波測勘等，檢查堤防構造物之使用狀況與內部損壞狀態，包含結構體內部裂縫及淘空狀況等情形，以便未來做為堤防管理、維護之參考依據，以及尋求有效維修與補強方案，擬委外辦理安全性評估分析及研擬改善方案。

The visual inspection results of the levee are 106 damage places, of which are 28 places in Xiuguluan River, 37 places in Fuyuan River, and 41 places in Hongye River. The damage level of them are planned to improve except 5 places needed notice to improve. The working line length of ground penetrating radar are up to 36,330.5 meters, of which 741 meters were measured slight hole signal, 16.5 meters measured moderate hole signal, their ratio to the total length are 2.04% and 0.05% respectively. Regarding to the comprehensive test results, the neighborhood levee slope above the hole signal is often accompanied by cracks, suggesting that levee holes due to emptied by external water infiltration through the damage such as cracks. The shock wave detection length is 500 meters, the test results show that the high and low of wave speed can represent the loose and tight degree of material differences in the same material condition. If there is a large crack on the levee slope, it will affect the test results. The compressive strength of the core specimen was between 102 kgf/cm2 and 499 kgf/cm2, and the concrete strength value of the Matsu-3 levee was found slightly lower. The compression test results of the other levees were more than 188 kgf/cm2, they are larger than the original design strength of 175 kgf/cm2. The levee assessment results show that the levees are generally in good condition and the scores of the levee sections ranged from 9 to 50, including 37 levees are planned improvement and 87 levees are normal. Therefore, currently the program should focus on key point inspections, to observe whether the trend of increasing damage to change, in order to master the status of the program area levee during the flood season. The restoration method of damage point within the program area is intended to use surface closure method mainly and local repair method to prevent the external water continued invasion of the levee, the estimated restoration cost is NTD 3,373,000.