頁籤選單縮合
題名 | 蛇籠保護方式對橋墩局部沖刷之影響=Effects of Gabion Layout on Local Scour Around Bridge Piers |
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作者 | 周憲德; 戴華鍇; 陳世清; | 書刊名 | 中國土木水利工程學刊 |
卷期 | 11:2 1999.06[民88.06] |
頁次 | 頁311-316 |
分類號 | 441.816 |
關鍵詞 | 橋墩; 局部沖刷; 蛇籠; 沖刷深度; Bridge pier; Local scour; Gabion; Scour depth; |
語文 | 中文(Chinese) |
中文摘要 | 本文針對矩形橋墩在未保護和受蛇籠保護情形下之局部沖刷進行試驗分析與探討 。試驗渠道為一動床試驗水槽:長400cm、寬60cm、砂深7.4cm,渠道之流況則控制在亞臨界 流(亦即福祿數小於1)。試驗橋墩為長12.4cm、寬4.6cm之矩形橋墩;保護橋墩之蛇籠則以 長條狀之不織布製成並圍繞橋墩四周。影響橋墩保護效應之三個主要考量因子為保護層頂端 至底床高度差z,橋墩寬度a 及含橋墩保護層之迎水寬a 。由實驗結果分析可知:有蛇籠保 護工之橋墩確實能減少沖刷深度,保護效果較佳之方式為多階保護之方式(其為底部圍繞較 多層而漸往上縮之型態),多階保護約可減少沖刷深度50%;單層保護亦可減少沖刷深度約 20%,且有蛇籠保護之橋墩沖刷坑之剖面變化較為平緩。在有蛇籠保護情況下,橋墩周圍最 大之沖刷深度位置為離橋墩周圍較遠,而沖刷之範圍則無太大之差異。經由實驗結果比較, 蛇籠保護層之頂端高程應位於沖刷坑內,若其低於沖刷坑則無效果,如保護層之頂端高於河 床則反會加深最大沖刷深度。 |
英文摘要 | The scour protection for bridge piers by nonwoven gabions was investigated experimentally in this study. The flume, with a test section of 400cm long and 60cm wide, contains a sand bed of 7.4cm in thickness and a rectangular pier of 4.6cm wide and 12.4cm long. The layout of the pier protection is characterized by three major parameters; the difference in elevation between the foundation top and the stream bed, z; pier width, a ; and foundation width, a . Experimental results showed that the multi-layer type reduces the scour depth to about 50%, while the one-layer type with gabions to about 20%. By using the nonwoven gabions, one can find the bed shape of the scour holes to be smoother than that of the scour holes without any protection. In general, the scour area is not sensitive to different protecting methods. |
本系統之摘要資訊系依該期刊論文摘要之資訊為主。