鋼筋混凝土加強砂石造重力式防砂壩排水孔水理現象之研究

Abstract

In this study, experiments focused on the position of drainage holes at the downstream side of gravity check dam of reinforced concrete frame filled with sediment. This study discussed the Hydraulic Characteristics under the combinations of two types of refilled sediment, four drainage holes with different diameter, and three different water depths. The experiment result indicated that the drainage hole would be arranged higher than the plant flume to avoid disturbance on the sand and plant inside flume. Experimental findings also discovered that the flow velocity within drainage hole was affected strongly by refilled sediment over than the water depth. Meanwhile, the diameter of drainage hole was the main factor affecting the flow velocity of drainage hole: larger the diameter the faster velocity.

本試驗針對鋼筋混凝土加強砂石造重力式防砂壩下游壩面所設置的排水孔進行試驗，本文以二種不同標準偏差之回填砂石、四種不同孔徑之排水孔及三種水位高來探討排水孔的水理現象。 經試驗結果顯示，排水孔的位置宜配置於植生槽上方，以避免對植生槽中的土體和植物造成影響。而排水孔之流速受回填砂石之影響程度大於受水頭之影響程度。且孔徑之大小為影響排水孔流量之最主要因素，排水孔之孔徑愈大，流量亦愈大。