Summary: | 碩士 === 國立成功大學 === 水利及海洋工程學系碩博士班 === 97 === Nowadays, we often build a series of spur dike groups for the embankment security, and use silt of the deposit between spur dikes to protect the embankment, but disadvantage is that several spur dike groups have to be build for bringing the best effects. Besides, due to the flow that impact on a head of the spur dike, the deeper scouring hole will be formed there easily, and the damage of the spur dike would also caused. In this article, we replaced effects of the spur dike groups with the efficacy of the in-line Porous Basket groups and improved defects of the spur dike groups.
In the following, we will focus on an observation of scour and deposit of Porous Basket groups. In the experiment, we changed an included angle of porous basket groups and flow, the interval between the two Porous baskets, then the best set up angle and interval was decided. Next, we tested to have Porous Basket groups raising to the bed and submerging under the water surface. Furthermore, we performed an series of discussions about: (1) position of maximum scouring and depositing, (2) an included angle of the scouring Belt and flow, (3) the magnitude of the maximum scouring and depositing, (4) the section of position of maximum scouring and depositing.
From what has been discussed above, we can conclusion that the best set up angle and interval was 30∘, 2 times diameter of the Porous Basket, respectively. From the experiments, Porous Basket groups have the best diversion effect, maximum scouring and depositing total magnitude which having no raising height and no submergence under the water surface. It could be benefited on protecting downstream of Porous Basket groups when the flood through Porous Basket groups flow toward the scouring Belt.
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