泡沫流体对堤基土体渗流特性影响分析

Effect of foam fluid on seepage characteristic in embankment foundation

针对泡沫流体对土体渗流的影响机制仍不清晰的问题,开展了室内无泡沫流体渗透破坏试验与泡沫流体抑制渗透破坏试验,对土体渗流特征及泡沫流体对土体渗流的影响进行了研究。试验结果表明:泡沫流体对堤基土体渗流具有显著调控作用,可通过滞留在孔隙中的气泡增大渗流阻力,将局部土体转变为非饱和状态,增强土体抗渗性能;泡沫流体可延长渗流路径,降低水力梯度,抑制土体渗透破坏的发展。

The influence mechanism of foam fluid on the seepage in the embankment foundation and the development of embankment seepage failure are unclear.In this study,the seepage failure experiment without foam fluid and the seepage failure experiment with foam fluid are carried out to investigate the characteristics of seepage in soil during the development of seepage failure and the influence of foam fluid on soil seepage.The experimental results show that foam fluid has a significant impact on the seepage in soil.The flow resistance greatly increased by the foam bubble trapped in pores,while the soil is turned to unsaturated state,which leads to the enhanced impervious performance.Besides,the flow path becomes longer due to the existence of foam fluid,which reduces the hydraulic gradient,and in turn significantly restrains the development of seepage failure of the embankment foundation.