非稳定流作用下管涌发生发展的室内试验及理论分析  

Laboratory simulation and theoretical analysis of piping mechanism under unsteady flows

作　　者：陈亮[1,2] 雷文[1,3] 张红宇[3] 赵敬川[3] 李佳[3] 

机构地区：[1]河海大学岩土力学与堤坝工程教育部重点实验室,江苏南京210098 [2]水利水运工程教育部重点实验室重庆交通大学,重庆400743 [3]河海大学岩土工程科学研究所,江苏南京210098

出　　处：《岩土工程学报》2013年第4期655-662,共8页Chinese Journal of Geotechnical Engineering

基　　金：重庆交通大学水利水运工程教育部重点实验室暨国家内河航道整治工程技术研究中心开放基金项目(SLK2011A02)

摘　　要：管涌问题是水利工程中广受关注的一大难题。通常针对管涌的研究是基于稳定水头条件下的,而非稳定流作用下,水位的升降变化与稳定流情况不同,水位势能的转变速率,施加于土颗粒的主动动量异于稳定流,导致土体发生管涌的规律也有别于稳定流情况。首先根据理论公式的计算,提出非稳定流作用下试样发生管涌破坏水头低于稳定流水头的假想;同时指出,试验过程中土颗粒的运移规律在小范围区域内具有很大的随机性。最后,在理论研究的基础上设计试验,通过控制供水水头,使水头在近似正弦曲线变化的情况下升降循环,进行管涌试验。在试验过程中监测试样内部各部位的渗流参数变化情况,对理论进行了验证。The problem of piping has gained widespread concern in hydraulic engineering. Usually, the researches on the piping are based on the steady flows. Under the function of unsteady flows, the variation of water level is different from that in the case of steady flows. The transformation rate of water potential that active momentum imposes on soil particles differs from that in steady flows, leading to the difference of the law of soil piping from the situation of unsteady flows. According to the calculation of theoretical formula, the hypothesis that water head of soil piping destruction under unsteady flows is lower than that under the steady flows is confirmed, and it is also pointed out that the migration law of soil particles has great randomness in a small area during the experiment. The experiment is designed based on the theoretical studies. By controlling water head, the piping tests on the soil samples under the situation that the water head changes in approximate sine curve are carried out. The correctness of theoretical analysis is verified by monitoring permeability changes of each part within the samples.

关 键 词：非稳定流 管涌 破坏水头 渗透系数 

分 类 号：TU41[建筑科学—岩土工程]