软土含砾地层斜孔成孔方法探讨     

卢文阁  池景军 《水文地质工程地质》1997,24(4):58-59

在锚固工程成孔中，软土含砾地层成孔困难，钻进效率低，效率效益差，针对这种情况分析了地层特点和采用不同成孔方法施工存在的问题，找出了一种比较适应的钻进成孔方法，并通过生产实践证明效果较佳，为软土含砾地层倾斜孔成孔提供了一种新方法。  相似文献   

旋挖钻机与双聚合泥浆在桩基施工中的应用          下载免费PDF全文

朱艳峰  任凤鸣王红 袁兵 《地质与勘探》2003,39(4):92-94

介绍了旋挖钻机和双聚合泥浆在工程中的应用，通过工程实例介绍了旋挖钻机的施工方法，着重介绍了双聚合泥浆的制备、特点和技术要求。  相似文献   

Characterizing the rheology of laterite slurries     

Brian C. Blakey  David F. James   《International Journal of Mineral Processing》2003,70(1-4):23-39

The viscous behaviour of laterite slurries was characterized by measurements of shear stress at constant and changing shear rates. Steady state stresses were obtained after accounting for the settling solids: the values show that the fluids possess viscosities of order 100 mPa s and are moderately shear-thinning, for solid volume fractions from 0.06 to 0.18 and for shear rates between 10 and 1000 s⁻¹. Transient stress measurements were made for steps down in shear rate and for ramps down and up in shear rate. It was found that the Bingham–Maxwell model provides good fits to the transient data, both at low concentrations, where yield behaviour is dominant, and at high concentrations, where elasticity is dominant. For volume fractions of 0.10 or greater, relaxation times were found from step tests to be of order 10 s, but relaxation times found from the ramp tests were generally several times higher.  相似文献   

悬浮液进样—石墨炉原子吸收光谱法测定琥珀中微量铅   总被引：3，自引：0，他引：3       下载免费PDF全文

陈世忠 《岩矿测试》2003,22(3):228-230

报道了以NH4H2PO4为基体改进剂，采用悬浮体制样石墨炉原子吸收光谱法直接测定琥珀中微量铅的方法。试验了影响测定的主要因素。在优化实验条件下。方法的检出限为0．038μg／g，Pb的质量浓度为0～80μg／L时，工作曲线线性关系良好。对于ω(Pb)=5．71μg／g样品的测定，相对标准偏差(RSD，n=5)为6．83％。  相似文献   

岩溶地区冲孔灌注桩的施工方法     

吴辰光 《中国煤田地质》2007,19(A01):63-64,73

以龙岩地区岩溶地带某一项目施工为例，分析冲孔灌注桩孔内漏浆、塌孔的原因，探讨在岩溶地区预防和处理塌孔的方法：改善泥浆品质，安放钢护筒，挤压黄土入裂隙，减小泥浆渗透，以及分层加入一定量水泥，使其形成水泥土护壁层。实践证明，诸类方法的使用可有效遏制孔内漏浆和塌孔，提高施工效率。  相似文献   

Additives for Slurry Shields in Highly Permeable Ground   总被引：2，自引：0，他引：2  

P. Fritz 《Rock Mechanics and Rock Engineering》2007,40(1):81-95

Summary. For tunneling projects in saturated soils tunnel boring machines (TBMs) with slurry shields are widely used. However, in coarse, highly permeable soils the suspension penetrates the ground and the required support pressure cannot be built up. For the Zimmerberg Base Tunnel near Zurich permeabilities much greater than 10⁻³ m/s were expected. This value is usually considered as the critical limit for the applicability of slurry shields. Therefore it was aimed to find additives for the bentonite suspension which would allow it to attain a higher suspension pressure. For these investigations an apparatus has been developed. It allows the maximum attainable support pressure for a given suspension and a ground to be determined. It reflects the real situation, produces reproducible results and is insensitive to the inevitable variation of individual parameters. In the tests the additives polymer, sand and vermiculite were studied and their effects on the attainable maximum suspension pressure investigated. For the best combination, i.e. with a well defined proportion of the individual components, suspension pressures could be attained which were about 10 to 20 times higher than those with an ordinary bentonite suspension. Successful excavation of the Zimmerberg Base Tunnel proved the validity of the laboratory tests containing 200 kg bentonite per m³ water.  相似文献   

地方病高发区成井用胶质水泥浆的试验研究          下载免费PDF全文

冉德发叶成明  王建增郑继天 汪敏 《探矿工程》2007,34(3):1-4

通过地方病高发区成井用胶质水泥浆的试验研究，以普通水泥和膨润土为基本材料，同时添加改善材料性能的外加剂，研制了一种用于高砷、高氟、高矿化度地区水井成井的止水材料，具有流动性好、抗渗性高、不收缩、完全无毒、价格低廉等特点，特别是其高抗渗性和不收缩性非常适合地方病区成井时隔离劣质含水层，保证优质含水层与劣质含水层互不串通、不渗漏、不污染。  相似文献   

环境矿物、SAP、化学固沙浆材综合治理荒漠初探   总被引：8，自引：3，他引：5  

葛学贵  黄少云  马广伟  陈亦凡  靳化才  杨密纯 《岩石矿物学杂志》2001,20(4):511-514

介绍了水玻璃-乙酸乙酯、植物栲胶化学固沙浆材在柱撑蒙脱石、缺铝型沸石的制备方法及性能,并将柱撑蒙脱石、缺铝型沸石、SAP、生根素等以一定的配比和方式复合在一起,制备成具有保水、保肥、保墒等多项功能的“复合富水营养包”,实验室初步证明,在无水、无肥、昼夜温差较大,不采取任何植保措施的情况下,营养包可使树苗在沙土中度过3个月的成活期。根据两种固沙浆材的特性及营养包的功能,提出一种新的治理沙漠的设想;用化学固沙浆材料在较大范围内固定流沙,为树木生长创造一个相对稳定的环境,然后用营养包保活单株树木,当大量树木构成规模林带、林地后,即可实现地下保水、地表固沙、地上成林三维结合的立体综合治荒目标。  相似文献   

电热蒸发—电感耦合等离子体原子发射光谱及其在痕量稀土分析中的应用   总被引：4，自引：0，他引：4  

江祖成  胡斌 《岩矿测试》2000,19(2):122-128

评述了电热蒸发电感合等离子体原子发射光谱分析（ＥＴＶ－ＩＣＰ－ＡＥＳ）联用技术的新近进展及其在痕稀土元素检测中的应用。从原理、分析性能、方法及应用诸方面对以聚四氟乙烯（ＰＴＦＥ）悬本为化学改进剂的氟化辅助电热蒸发（ＦＥＴＶ）－ＩＣＰ－ＡＥＳ新技术作了全面的介绍,引用参考文献２８篇。  相似文献   

悬浮液进样石墨炉原子吸收光谱法测定环境样品中痕量铅          下载免费PDF全文

刘汉东  刘国珍 《地球科学》2000,25(5):532-535

提出了悬浮液进样石墨炉原子吸收光谱法测定环境样品中痕量铅的分析方法.讨论了悬浮颗粒粒径、悬浮液浓度、悬浮稳定剂、基体改进剂等因素对测定结果的影响.实验结果表明: 样品粒径 < 38μm, 以0.2g/L的Triton - 100为悬浮剂, 3g/L的(NH₄)₂HPO₄为基体改进剂, 电磁搅拌进样可简便快速地测定地质样品中的痕量铅, 方法的检出限为0.10ng/g, 精密度为3.31% (n =10).43GSD标样测定结果与推荐值一致   相似文献