股流作用下铁矿砂坡面侵蚀特征研究

发布时间：2018-05-02 15:12

本文选题：铁矿砂 + 径流量　；参考：《山西农业大学》2015年硕士论文

【摘要】：在坡度为15°,20°和25°,放水流量为1.5L/Min、2.0L/Min和2.5L/Min的情况下,对铁矿砂坡面进行股流冲刷模拟试验,研究其产流产沙规律、颗粒坡面运移特征及水沙关系。研究结果表明：(1)在稳定股流冲刷的作用下,铁矿砂坡面颗粒运移既具有阵发性和波动性,又具有一定程度的跳跃性、突发性。(2)由试验结果可知,不同坡度和流量的坡面产沙量均会随着坡度和流量的增加而增大,按其大小排序为：M25。M20。M15°,M2.5L/minM2.0L/min M1.5L/min;径流量按其大小排序为：Q25°Q20°Q15° Q2.5L/min Q2.0L/min Q1.5L/min;但当流量为2.5L/min时,Q20。Q25。Q15。。(3)坡面产流时间主要受流量变化影响；在不同坡度和流量梯度下的铁矿砂帔面颗粒运移特征存在明显的差异性。小坡度、低流量条件下,坡面颗粒运移主要分为三个阶段：前期蠕动变形阶段、中期侵蚀运移阶段和后期稳定运移阶段。大坡度、高流量条件下,主要有大规模滑落侵蚀运移和稳定运移两个阶段,坡面颗粒运移的突发性更为明显和强烈。(4)对试验数据进行统计分析,不同坡度与流量下坡面累积产沙量与累积径流量均呈现较好的幂函数关系：y=axb;在小流量作用下,坡度的变化对坡面侵蚀量的贡献较为显著,而随着流量的增大,坡度已不再是坡面侵蚀量增大的主因。
[Abstract]:Under the conditions of 15 掳/ 20 掳and 25 掳, and the discharge rate of 1.5L / min 2.0L / Min and 2.5L/Min, the runoff scour simulation test was carried out on the slope of iron ore to study the regularity of runoff and sediment yield, the migration characteristics of granular slope and the relationship between water and sediment. The results show that the particle migration on the slope of iron ore is both paroxysmal and fluctuating under the action of steady stream scouring. The sediment yield increased with the increase of slope and flow rate. The order of runoff is: M25.M20.M15 掳, M2.5L- / minM2.0L / min, M1.5L / min; runoff: Q25 掳Q20 掳Q15 掳Q2.5L/min Q2.0L/min Q1.5L / min; but when flow rate is 2.5L/min, runoff time is mainly affected by flow rate change. There are obvious differences in grain migration characteristics of iron ore frame surface under different slope and flow gradient. Under the condition of small slope and low flow rate, the grain migration on the slope can be divided into three stages: the early creep stage, the intermediate erosion migration stage and the late stable migration stage. Under the condition of large slope and high flow, there are two stages of large scale sliding erosion migration and stable migration, and the sudden occurrence of grain migration on slope surface is more obvious and strong. There is a good power function relationship between the cumulative sediment yield and the cumulative runoff under different slope and flow rate. Under the action of small flow, the slope change has a significant contribution to the slope erosion, but with the increase of the flow rate, The slope is no longer the main reason for the increase of erosion on the slope.
【学位授予单位】：山西农业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S157.1

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