贴砾过滤器贴砾层渗透性试验研究OA

Pre-packed screen pipes and gravel packing are widely used in geothermal exploitation,hydrological observation and other projects.The main working parts are gravel layer and pre-packed layer.In this paper,the permeability of quartz sand was researched which is commonly used as the pre-packed material.Through adjusting the particle size and fine particle content of the sand samples,the permeability of quartz sand before and after consolidated in saturated state is tested,the effects of the particle size and gradation on the permeability of quartz sand before and after consolidated are analyzed,and the permeability difference in the same conditions is also analyzed by sorting the tested data.The results show that the permeability coefficient of sand samples decreases with the particle size.Changes in medium sands is the biggest and smaller in fine sand.The permeability coefficient of sand samples decreases as the fine particle content increases.The minimum permeability coefficient of composite sand is smaller than that of the sand that constitutes its fine particle group.Under the same conditions,the permeability of loose coarse quartz sand is better than that of the consolidated quarts sand,and the permeability of the medium and fine consolidated quartz sand is better than that of loose quartz sand.