饱和方式和泥岩含量对堆石料渗透系数的影响

INFLUENCES OF SATURATION MANNERS AND MUDSTONE CONTENTS ON SEEPAGE COEFFICIENT OF ROCKFILL

在进行渗透试验时,对于高渗透性的过渡料,主堆石、次堆石采用水头饱和;对于中渗透性、甚至是低渗透性的垫层料,采用抽气饱和则可节约很多时间。由于地质构造等原因,岩体中也常含有泥岩夹层。因此有必要探讨饱和方式和泥岩含量对堆石料渗透系数的影响。针对无锡马山抽水蓄能电站水库大坝的填筑材料,利用粗粒土渗透仪进行一系列的渗透试验,探讨饱和方式和泥岩含量对堆石料渗透性的影响。研究结果表明,饱和方式对堆石料渗透系数的影响不大;堆石料中泥岩含量增加,渗透系数减小,当泥岩含量足够大时,堆石料的渗透系数将变得很小,堆石料的渗透系数与其泥岩含量之间存在负指数关系。

When performing seepage tests,hydraulic saturation is used for transitional rockfill,main rockfill and secondary rockfill with high permeability permeable.While for bedding rockfill which has moderate or even low permeability,vacuum saturation can be used to save much time.Due to some reasons such as geological structure,usually there are mudstone interlayers in rock.Therefore,it is necessary to study the influences of saturation manners and mudstone content on seepage coefficient of rockfill.Utilizing osmoscope for coarse-grained soil,a series of permeability tests are performed on the filling material of the pumped storage power station dam in Mashan,Wuxi City.Saturation manner hardly affects the seepage coefficient of rockfill;and the seepage coefficient decreases when the mudstone content in rockfill increases.When the mudstone content is high enough,the seepage coefficient decreases to a very low value.Furthermore,the relationship between seepage coefficient of rockfill and mudstone content is negative exponent.