| 摘要: |
| 窝崩涉及到水、土两方面的交互作用,又因其具有发展速度快,位于水下难以观测等特点,致使到目前对窝崩的成因机理尚不完全了解,存在不同观点。选择和畅洲左汊洲头进口侧2012年发生窝崩(子窝崩)作为研究对象,此窝崩为在原已发生窝崩(父窝崩)的窝塘湾腰上的继发性窝崩。比较了父窝塘及口门附近长江深槽窝崩前近4年的地形变化,发现窝崩口门外长江地形呈淤积状态,这与现在深槽冲蚀引起窝崩的概念不符；父窝塘上湾腰地形2011年淤积,2012年预测冲刷,说明在较浅槽内一个水文年内的河床冲刷可引发窝崩；子窝崩发生前后,父窝塘下部区域地形变化不大,说明窝崩产生的泥沙在近底层向较低处输移,对周边相对较高河床地形影响不大。 |
| 关键词: 长江 和畅洲 窝崩 窝塘 |
| DOI： |
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| 基金项目:国家自然科学基金资助项目（51779148,51679147，51579151）；国家重点研发计划资助项目（2018YFC0407302，2018YFC0407402）；江苏省水利科技项目（2018021） |
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| Discussion on the mechanism of pit collapse from the topographic change of father’s and son’s scour pool |
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yingqiang1, Zhang Xinnong1, Luo Longhong2, Su Changcheng3
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1.Nanjing Hydraulic Research Institute;2.Water Resource Engineering Planning Office of Jiangsu Province;3.Yangtze River management office of Zhenjiang City
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| Abstract: |
| The pit collapse is a sloop failure that involves the interaction of water and soil. Its formation mechanism is still not fully understood because of its rapid development and difficult observation underwater. A typical collapse occurred at the entrance of the left branch of Hechangzhou Island in 2012 in the lower Yangtze River, that is a reoccurring failure with a father-son’s caving pond, is chosen as a case study by comparing the topographic changes of main channel near the mouth of the pond in the past four years before the son’s collapse. It is shown that there was siltation in the main channel and not erosion which is inconsistent with the common situation. The topography changes of the pond upstream bend between 2011 and 2012 indicates that the pit collapse can occurred when the riverbed of a shallow trough within a hydrological year was scoured. Before and after the occurrence of the son’s collapse, the bending topography of the downstream side of the father's Scour pools did not change much, which indicated that the sediment generated by the pit collapse moved from the bottom to the lower level, and had little effect on the relatively high riverbed topography around it. |
| Key words: Yangtze River Hechang island pit collapse scour pools |
