宁夏平罗盐碱地排水渠道抗冲性野外水槽试验

The Field Flume Experiment of Drainage Channel Erosion Resistance in the Pingluo Saline Land of Ningxia

采用水槽试验的方法来分析宁夏平罗西大滩地区分别以白僵土、沙土所铺设成的排水渠道的稳定性。结果表明,用白僵土铺成的渠道有很强的抗冲性,白僵土的侵蚀及渠道的冲淤变化,主要归因于反复对白僵土的浸润湿化与脱水干燥;沙土粘性小,抗冲性弱,用沙土铺成的渠道在水流作用下纵向横向变形都很大,随着试验的进行,沙土逐渐被河流冲刷带走,渠道中出露的白僵土颗粒能起到抗冲铺盖层的作用,阻止渠道进一步在纵向上的变形。对比西大滩常见的白僵土和沙土的抗冲性发现,用白僵土铺成的渠道稳定性好,如果能够很好的解决白僵土浸润湿化与脱水干燥问题,则以白僵土构建排水渠道将会维持其稳定性。

This paper use flume experiments to analyze the stability of the drainage channels,the two different channels were paved by Baijiangtu and sand in the saline land of Ningxia,respectively.From the experiments,we can draw conclusions that the channel which paved by Baijiangtu has a strong resistance to water flow erosion.The minor change of the channel erosion and deposition is due to the repeated wetting and air drying.The sand is easy erosion by water flow,so the channel which paved by the sand has a large deformation in the longitudinal and transverse under the water flow.But the mud-gravel composed of the Baijingtu on the channel bed restrict the further longitudinal deformation.Comparing the two test we can draw a conclusion that the Baijiangtu could be used to construct the drainage channel in the Pingluo saline land of Ningxia,if the wetting and air drying problems can be solved.