摘要
影响重塑细粒土渗透系数测定的因素之一是土样的制备。以华北地区某平原水库粉质黏土为研究对象,通过变水头试验和压汞实验,研究制备试样的固结时间和渗流起始水头对水工建筑物建筑材料渗透性和孔隙的影响。结果表明:制备试样的固结时间对渗透系数的影响更显著,固结8 h的渗透系数是24 h的3.8倍;起始水头对渗透系数的影响不超过2倍;固结时间越短,渗透系数受水头的影响越大;对重塑粉质黏土,以至少固结10 h且起始水头为100 cm为宜;固结使大孔隙(>40μm)减小为小孔隙(<10μm),土中的孔隙趋于均匀;对渗透性起决定性作用的是10~40μm的孔隙含量,随其增多,渗透性增大。结论对重塑细粒土渗透系数的测定和工程中渗透性的应用有借鉴意义。
One of the factors affecting the determination of the coefficient of permeability of remolded fine-grained soil is the preparation of soil samples.Variable head permeability test and mercury injection test of remolded silty clay in the plain reservoir in North China are conducted to seek the changes of permeability and pore of building materials for hydraulic structures caused by initial water head and consolidation time.The effect of consolidation on the permeability coefficient of silty clay is significant.The permeability of 8 hours of consolidation time is 3.8 times that of 24 hours.The initial water head also has an effect on the permeability of the remolded silty clay,but it does not exceed 2 times.The shorter the consolidation time,the larger the permeability coefficient and the rate of change under the influence of the water head.For remodeling silty clay,it is appropriate to consolidate for at least 10 hours with a starting water head of 100 cm.Consolidation causes large pores(>40μm)reduced to small pores(<10μm),the pores in the soil tend to be uniform.The pore content of 10~40μm plays a decisive role in permeability,the permeability increases with its increase.The conclusions are useful for the determination of the coefficient of permeability for remolded fine-grained soil and the application of permeability in engineering.
作者
王华敬
杨洁
王坤
张艳青
孙颖君
WANG Hua-jing;YANG Jie;WANG Kun;ZHANG Yan-qing;SUN Ying-jun(College of Water Conservancy and Civil Engineering,Shandong Agricultural University,Tai'an 271018,Shandong Province,China;Shandong Coal Geology Bureau,Qingdao 266555,Shandong Province,China)
出处
《中国农村水利水电》
北大核心
2020年第5期84-86,91,共4页
China Rural Water and Hydropower
基金
国家科技支撑计划项目(2015BAB07B05)
山东省重点研发计划项目(2017GSF16104)。
关键词
重塑粉质黏土
变水头渗透试验
压汞法
固结时间
渗透性
remolded silty clay
variable head permeability test
mercury injection test
consolidation time
permeability
