COLLABORATIVE RESEARCH: Experimental Study of Downstream Fining in Coarse-Grained River Channels

合作研究：粗粒河道下游细化的实验研究

基本信息

批准号：
9205511
负责人：
Peter Wilcock
金额：
$ 8.25万
依托单位：
Johns Hopkins University
依托单位国家：
美国
项目类别：
Continuing Grant
财政年份：
1992
资助国家：
美国
起止时间：
1992-07-01 至 1995-06-30
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=9205511&HistoricalAwards=false
关键词：
COLLABORATIVE RESEARCH Experimental Study Downstream

项目摘要

This is a renewal of a 2-year project whose overall goal is to study downstream fining by aggradation and selective deposition in gravels. The main results so far have produced downstream fining by a factor of two in a channel 50 m long and 0.3 m wide at the St. Anthony Falls Hydraulic Laboratory (SAFHL), demonstrating unequivocally that selective deposition is an effective fining mechanism and that it can be studied in laboratory experiments. In parallel experiments at Johns Hopkins University (JHU), a novel colored-grain system is providing the fractional-transport data base needed to perdict the fining observed at SAFHL. This phrase now involves a series of runs a SAFHL with a channel width of 2.0 m; this will produce braided topography, enabling invesitgation of the effect of lateral sorting and topography on downstream fining. The present fractional-transport program at JHU, will continue adding components on the effect of sediment feed versus recirculation and the influence of small-scale sedimentary features. Finally, a concurrent set of runs at MIT to examine local lateral sorting in a 1.0 m wide channel as well as the effects of varying deposit geometry and percent extraction is planned. This research seems as the first real connection between engineering hydraulics and fluvial sedimentology and represents fundamental research related to sediment transport mechanics.

这是对一个为期两年的项目的续签，其总体目标是通过敏捷和选择性沉积在砾石中研究下游罚款。到目前为止，主要结果在50 m的通道中造成了下游罚款的两倍，在圣安东尼瀑布液压实验室（SAFHL）宽度为0.3 m，毫无疑问地表明，选择性沉积是一种有效的罚款机制，可以在实验室实验中进行研究。在约翰·霍普金斯大学（JHU）的并行实验中，一种新颖的彩色颗粒系统提供了捕获Safhl观察到的罚款所需的分数传输数据库。现在，该短语涉及一系列运行的SAFHL，通道宽度为2.0 m；这将产生编织的地形，从而使横向分类和地形对下游罚款的影响产生影响。 JHU目前的分数传输计划将继续添加有关沉积物饲料与再循环效果以及小规模沉积特征的影响的组件。最后，计划在MIT上进行一套运行，以检查1.0 m宽通道中的局部横向分选以及不同的沉积物几何形状和提取百分比的影响。这项研究似乎是工程液压和河流沉积学之间的第一个实际联系，代表了与沉积物传输力学有关的基本研究。