Ma Qiang, Xiang Jun-Chen, Wu Nian-Ze, Xiao Heng-Lin
School of Civil Engineering and Environment, Hubei University of Technology, Wuhan, People's Republic of China.
Sci Rep. 2020 Jul 9;10(1):11296. doi: 10.1038/s41598-020-68332-4.
With the application of fiber-reinforcement technology, the mechanical properties of silty clay are improved with fiber reinforcement. However, the variation of permeability coefficient and other parameters of flax-fiber reinforced silty clay have not been sufficiently studied. In this study, the permeability of flax-fiber reinforced silty clay soaked with zinc-contaminated solution under different osmotic pressure was tested by a flexible-wall permeameter, and the effects of zinc-ion concentration and confining pressure on the permeability of flax-fiber reinforced silty clay were studied. Genius XRF was employed to detect the types and quantity of metal elements in the specimens, thereafter, the reasons for the change of permeability were explained from chemical and microscopic perspective. The results showed that the permeability coefficient of flax-fiber reinforced silty clay decreased significantly with the increase of zinc-ion concentration in a low concentration (about 1-10 mg L). While in a high concentration (about 100 mg L), the permeability coefficient of flax-fiber reinforced silty clay changed little with the increase of zinc-ion concentration. While the flax-fiber reinforced silty clay was not soaked with zinc-ion solution, the permeability coefficient of the specimen increased with the increase of confining pressure. However, when the flax-fiber reinforced silty clay was soaked with zinc-contaminated solution, the permeability coefficient first decreased and then tended to be constant with the increase of confining pressure. With the increase of confining pressure, the porosity of flax-fiber reinforced silty clay decreased, and with the increase of zinc-ion concentration, the porosity of flax-fiber reinforced silty clay first increased and then decreased.
随着纤维增强技术的应用，粉质黏土的力学性能通过纤维增强得到改善。然而，亚麻纤维增强粉质黏土渗透系数等参数的变化尚未得到充分研究。本研究采用柔性壁渗透仪测试了不同渗透压下浸泡在锌污染溶液中的亚麻纤维增强粉质黏土的渗透性，并研究了锌离子浓度和围压对亚麻纤维增强粉质黏土渗透性的影响。采用Genius XRF检测试样中金属元素的种类和含量，之后从化学和微观角度解释了渗透性变化的原因。结果表明，在低浓度（约1-10 mg/L）下，亚麻纤维增强粉质黏土的渗透系数随锌离子浓度的增加而显著降低。而在高浓度（约100 mg/L）下，亚麻纤维增强粉质黏土的渗透系数随锌离子浓度的增加变化不大。当亚麻纤维增强粉质黏土未浸泡锌离子溶液时，试样的渗透系数随围压的增加而增大。然而，当亚麻纤维增强粉质黏土浸泡在锌污染溶液中时，渗透系数随围压的增加先降低后趋于恒定。随着围压的增加，亚麻纤维增强粉质黏土的孔隙率降低，随着锌离子浓度的增加，亚麻纤维增强粉质黏土的孔隙率先增加后降低。
