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三重管高压喷射注浆在基坑隔水帷幕中的应用 总被引:2,自引:0,他引:2
三重管高压喷射注浆就是采用分别输送水、气和浆液3种工作介质的三重注浆管,使高压水、压缩空气冲击破坏土体,再让水泥浆液与土体搅拌混合,形成渗透系数为10^-7cm/s的固结体的岩土施工方法.它分为定喷和旋喷两种形式,适宜于地基加固和基础防渗. 相似文献
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海拉尔盆地贝尔凹陷三叠纪布达特群-早白垩世大磨拐河组储层孔隙纵向分布特征 总被引:6,自引:2,他引:4
贝尔凹陷是海拉尔盆地最有潜力的油气勘探地区.由于该区储层类型较多,实测孔隙数据较少,很难了解各类储层孔隙在纵向上的分布.根据铸体薄片数据,采用立方体模型来推算原生孔隙度,利用原生孔隙度和视孔隙度与埋深在纵向上的组合规律了解储层孔隙的现今分布特征.通过实验数据推测出该区储层可能发育3个次生孔隙带,分布在埋深1 000~1 200m、1 300~2 000 m和2 040~2 300m,其中1 300~2 000m次生孔隙带已被证实. 相似文献
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着重介绍在景洪水电站左岸下游渣场排水洞开挖施工中,对于Ⅴ类围岩洞段,针对不良地质条件下的隧洞开挖施工技术难点,应用超前小管棚预注浆、格栅钢架(或型钢支撑)、顶拱挂网、系统锚杆、喷射混凝土等多种支护措施,安全顺利地进行隧洞锁口和通过洞身段长达574 m的Ⅴ类围岩洞段,其中还包含3条断层破碎带。 相似文献
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介绍了SYB-100/100型双液变比注浆泵的工作原理、主要结构、技术参数、主要特点、使用情况及其广泛的市场前景。 相似文献
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农村剩余劳动力转移的理论研究与实践探索 总被引:10,自引:0,他引:10
本文用哲学、地理学、人口学和发展经济学的观点,对外国和中国农村剩余劳动力转移的理论进行了评析,并且对中外农村剩余劳动力转移的经验模式进行了归纳总结,旨在为我国解决农村剩余劳动力转移问题提供科学理论依据和实践经验。 相似文献
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Continental to global reconstructions of historic land cover/use are important inputs for many environmental, ecological and biogeochemical studies. While local to regional reconstructions frequently make use of old topographic maps and land use statistics, continental to global reconstructions are mostly model-based reconstructions. As a result they are subject to large uncertainties. A wealth of historic land cover/use maps and statistics have been produced and these are now more accessible due to the ending of copyrights and secrecy statuses, enthusiastic hobby communities and national cartographic institutes or cadastres that have a strategy towards data sharing with society. In this paper we made use of historic statistics and old topographic maps to demonstrate the added value for model-based reconstructions of historic land cover/use for Central Europe back to 1900. We harmonized these diverse data types and different types of historic land data were incorporated into the land use reconstructions. The added value of using these data was evaluated using historical maps by performing a reconstruction with and without the historic information. The accuracy of the land allocation in the historic reconstruction was improved by 16.5% using historic maps. Additionally, historic maps improved the representation of the spatial structure of landscapes. The historic land cover/use statistics used showed a strong agreement with independent estimates, like historic maps. 相似文献
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本文将沉积、成岩和储集性三者结合起来研究,建立了泥云坪压实沉积成岩相区、含膏云坪岩溶孔洞沉积成岩相区,膏泥云坪浅凹压 实交代充填沉积成岩相区等 三种沉积成岩类型,分析了各相区的沉积构造特征,成岩特征,储集性能,指出了含膏云坪岩溶孔沉和只成岩相带是天然气富集的最有利储集相带。 相似文献