【摘 要】
：
冰盖作为河流特定的上部约束,其下水沙变化(尤其弯道)对河道治理及生态环境意义重大.通过对什四份子河段进行野外试验,分析了冰盖对该河段水沙特性的影响.指出冰下水流流速垂线分布中,最大流速位置约在相对水深为0.4处,凸岸“抛物线型分布”特征明显.冰封期主流易位,垂线平均流速较大值主要集中在近凸岸侧.纵向流速分量较大,横向流速次之,垂向流速最小.在冰盖的影响下,冰封期泥沙浓度较低,但泥沙中值粒径(30～45μm)普遍大于畅流期(6～ 35 μm).
【机 构】
：
内蒙古农业大学水利与土木建筑工程学院,内蒙古呼和浩特010018;黄河水利科学研究院,河南郑州450003
论文部分内容阅读
冰盖作为河流特定的上部约束,其下水沙变化(尤其弯道)对河道治理及生态环境意义重大.通过对什四份子河段进行野外试验,分析了冰盖对该河段水沙特性的影响.指出冰下水流流速垂线分布中,最大流速位置约在相对水深为0.4处,凸岸“抛物线型分布”特征明显.冰封期主流易位,垂线平均流速较大值主要集中在近凸岸侧.纵向流速分量较大,横向流速次之,垂向流速最小.在冰盖的影响下,冰封期泥沙浓度较低,但泥沙中值粒径(30～45μm)普遍大于畅流期(6～ 35 μm).
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