Field tests of a sled system for beach profile measurement and of bed load sampler at T-shaped observation pier

海滩剖面测量雪橇系统和T形观察码头底荷采样器的现场测试

基本信息

批准号：
62550373
负责人：
KAWATA Yoshiaki
金额：
$ 1.41万
依托单位：
Kyoto University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1987
资助国家：
日本
起止时间：
1987 至 1988
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-62550373/
关键词：
Sand Drift Bed load transport Suspended load transport Bottom topography Sediment sampler Observation pier sheet flow 漂砂量岸沖方向漂砂海浜断面大潟海岸砂州反射

项目摘要

The in situ measurement of the bottom topography and the rate of sediment transport under storm wave conditions have been studied with T-shaped observation pier(TOP) at Ogata Wave Observatory, DPRI, Kyoto University. First of all, a bottom profiler equipped with a pressure sensor could be developed and secondly a bed load sampler was made on the basis of the ideas of local scour around the sampler and discharge of water from the opening. The principal conclusions are as follows:1. It is possible to get an accurate three dimensional bottom topotraphy with the profiler at TOP, even if under storm wave conditions.2. The beach processes around the pier is as same as those on the Ogata Coast. the dip and shoal are nearly stable year by year and this feature is well fixed under storm waves in winter. Moreover, the offshore sediment transport generated by the reflected waves due to concrete armor units lined up along the shoreline leads to loss of sediment in the shallow water area and increment of water depth. Especially, at the east end of the offshore wing of the pier, a strong undertow can be detected under swell wave conditions.3. The bed load sampler can trap the rate of sediment transport during a half wave period. The local scour around the lower hopper part of the sampler can fix it at the same position. The intake of sea water through the elbow pipe whose entrance is at the height of 50cm from the sea bottom can spread out during another half wave period.4. The data of bed load transport are fairly good agreement with the present formula of sediment transport by waves which is theoretically derived by the author.

在京都大学DPRI的Ogata Wave天文台上，已经研究了风暴波条件下的原位测量底部地形和在风暴波条件下的沉积物传输速率。首先，可以开发配备有压力传感器的底部轮廓器，其次是根据在采样器周围的本地搜索想法和开口处排出水的基础上制作了床负荷采样器。主要结论如下：1。即使在风暴波条件下，也可以在顶部获得精确的三维底部拓扑塑料。2。码头周围的海滩工艺与Ogata海岸的海滩工艺一样。倾角和浅滩逐年几乎稳定，此功能在冬季的暴风雨波下固定得很好。此外，由于沿海岸线的混凝土装甲单元衬里的混凝土装甲单元所产生的近海沉积物传输导致浅水区域中的沉积物损失和水深度的增加。尤其是，在码头离岸机翼的东端，可以在膨胀的波动条件下检测到一个强大的肢体。3。床负荷采样器可能会在半波周期间捕获沉积物传输速率。采样器的下部料斗部分周围的本地冲刷可以将其修复在相同的位置。在距海底50厘米高的肘管上，海水的摄入量可能会在另一半波段的时间内散布。4。床负荷运输的数据与作者理论上得出的波浪的当前沉积物传输公式相当良好。