共查询到18条相似文献，搜索用时 82 毫秒
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通用挖桩模具的设计及卵砾石层人工挖桩施工工艺湖南省地矿厅４０２队陆自雄长沙市气象科技大楼桩基工程，共计１４７根桩，桩长为１７～２２ｍ，桩径分别为１．２、１．４、１．８、２．０、２．２和２．４ｍ六种。施工地层从上至下为杂填层（厚２～４ｍ）、亚粘土及亚砂... 相似文献
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烧结式PDC钻头软模成型工艺研究 总被引：1，自引：0，他引：1
针对烧结式PDC钻头模具成型困难、生产效率低问题,研制出一种软模成型工艺制造模具。其要点在于首先制订软模成型工艺流程,然后分别确定基础模具、橡胶模具和陶瓷模具的成型工艺,再试制钻头。结果表明,使用这种方法制造钻头模具,能简化工序,提高生产效率,制作的钻头精度高,外观精美,一致性好。 相似文献
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结构面广泛存在于岩体工程中,其性质更是对岩体的破坏特性有着显著的影响。利用自主研发的起伏度可控的结构面制样模具制作出不同起伏角的结构面试块,并进行室内直剪试验,在此基础上研究起伏角对结构面抗剪强度的影响。自主设计研发的波状起伏结构面制样模具,可实现锯齿状、波状、规则与非规则等表面起伏形态结构面试样的制作。根据模具设计思路,参照结构面的野外实际特征,快速制作出表面起伏角分别为5°、10°、15°、20°、25°、30°的结构面试样进行室内剪切试验。在对试验结果分析的基础上,利用Barton所提出的JRC-JCS估算模型建立结构面起伏角与JRC之间的对应关系,综合考虑异性结构面上下强度差异,提出考虑起伏角影响的结构面抗剪强度公式。 相似文献
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大开发与西藏的地质环境保护 总被引：1，自引：0，他引：1
西藏是青藏高原的主体部分，特殊的地理位置和自然条件，塑造出西藏特殊的地质环境，西藏地质灾害分布广泛，类型较多，危害甚大，是全国地质灾害最严重的地区之一，主要地质灾害类型有泥石流，崩塌、滑坡，土地沙漠化，水土流失，冻胀融沉，盐碱化，碎石流，冰湖溃决，地震等，西藏高原分布有非常丰富的地质遗迹，其中地质地貌景观和现代冰川可谓全国之冠，西藏区内已知有各类地热显示区600多处，天然饮用矿泉水在西藏也广有分布，西藏的生态环境具有多样性，复杂性和脆弱性的特点，目前在总体上呈衰退趋势，成为我国生态环境极为脆弱，对外界干扰十分敏感的典型地区，为此，本文提出了西藏地质环境保护的对策和建议。 相似文献
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淮北矿区煤层气开采地质条件及开采方式的分析 总被引：2，自引：0，他引：2
淮北煤田属石炭二叠纪煤田，地质构造中等，煤系地层厚１２００ｍ，含煤层数多，煤层总厚度大，煤为气，肥煤，煤层气含量高，特别是宿县与临焕矿区最高，煤层气资源丰富，具备开发所需的地质条件，为华东煤地层气大规模开发的理想选区，宿东，宿南，南坪三个向斜为矿区煤层气开采的有利地块，它分布集中，地形平坦，靠近城市，市场广阔，具备统一规划，分步实施的有利条件。 相似文献
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云南属于矿产资源大省，矿业开发历史悠入，可追溯到公元前十二世纪的商代，至今已有3000多年，积累了非常丰富的经验和资料，现代科学技术极大地促进地质勘查和矿业开发的发展，但由于云南地质构造复杂，山高谷深，人烟稀少，不乏存在找矿盲区，因此，在使用高新科技手段勘查找矿的同时，“以史为证，以史为鉴”，挖掘历史记载中有用的矿业信息，仍不失为发展矿业，特别是发展地方矿业的途径。本刊将陆续发表薛步高多年来搜集，积累，考证的找矿史料，以期以新一代矿业开发提供信息，发挥作用。 相似文献
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烧锅营子金矿黄铁矿的化学成分标型特征 总被引：1，自引：0，他引：1
烧锅营子金矿床的黄铁矿形成于早，中，晚３期，是主要的矿石矿物和载金矿物，其中以中期黄铁矿为最主要的载金者。黄铁矿的化学成分为；ＴＦｅ４３．３４％－４５．５２％，Ｓ４６．５８％－４８．８６％，，与标准黄铁矿相比显示亏铁，亏硫特点，黄铁矿为含丰富的微量元素，有Ａｕ，Ａｇ，Ａｓ，Ｓｂ，Ｂｉ，Ｃｕ，Ｚｎ，Ｐｂ，Ｃｏ，Ｎｉ，Ｗ，Ｍｏ，Ｓｅ等。其中Ａｕ，Ａｇ，Ｃｕ，Ｐｂ，Ｚｎ，Ｂｉ含量较高，而Ａｓ，Ｓｂ低，Ｓ 相似文献
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旅游地的形象塑造是当今旅游地发展中的重要问题之一,兴文石海的形象塑造应以地貌景观特点为基础,按其塑造原理和技术要求,形成特色突出、符合市场需要的形象,以更好地吸引游客,促进旅游地的持续发展。依据RIS框架理念,兴文石海地质公园的旅游形象应从横向、纵向两维进行重塑。其旅游形象总体可以定位为"三绝喀斯特—僰苗风情绝"。为改变当前兴文石海旅游不景气的局面,应通过精心组织旅游线路,制定鲜明的旅游宣传口号,创新营销理念及方式,做好旅游形象的维护和拓展管理,把兴文石海优美的旅游形象根植于广大旅游者心里。 相似文献
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The paper presents the results of investigations of physical and chemical properties of after reclamation dust that is generated in the foundry industry. Universally applied mechanical reclamation processes of spent moulding sands generate large amounts of after-reclamation dusts containing mainly rubbed spent binding agents and quartz dusts. An amount of after-reclamation dusts—in dependence of the reclamation system efficiency and the reclaim dedusting system—can reach 5–10 % in relation to the total reclaimed spent moulding sand. After-reclamation dusts originated from spent moulding sands with different kinds of resins mostly belong to dangerous wastes, since they contain chemo-setting binders with dangerous substances removed in the reclamation process. None of the companies producing mechanical reclamation systems offers presently the complex technology and equipment for utilisation of after reclamation dusts, which would meet technical and economic expectations of foundry plants. The paper presents the results of research carried out at the Faculty of Foundry Engineering AGH UST in Cracow which aims on the determination of possibilities of using the post-reclamation dust generated during mechanical reclamation of used moulding sands with organic resins as a source of energy. Different dusts generated in the mechanical reclamation process of used organic sands, delivered from foundries, were tested to determine their chemical composition, granular characterisation and physicochemical properties. As a result of the investigations, possible ways to utilise the dusts are presented. 相似文献
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A reddish brown lateritic soil treated with up to 15% blast furnace slag was compacted with three compactive efforts, (standard
Proctor, West African Standard and modified Proctor) with moulding water contents ranging between 10 and 20% of weight of
dry mixture. Compacted samples were extruded and allowed to dry in the laboratory for 30 days with measurements taken every
5 days to monitor volumetric changes due to drying. Four specimens compacted on the wet side of optimum using standard proctor
effort; at the various slag treatments after 10 days of drying were subjected to four cycles of drying and three cycles of
wetting. The results obtained showed that the changes in mass and volumetric shrinkage were rapid within the first 5 days
of drying. These changes were proportional to the moulding water contents and were unaffected by the compactive effort. The
volumetric shrinkage strain increased with increasing moulding water content and compactive efforts. As the water content
relative to the optimum increased towards the wet side, the volumetric shrinkage strain increased and it decreased towards
the dry side. For all compaction energies, the initial degree of saturation increased and regardless of the slag content,
the volumetric shrinkage strain increased. As the slag content increased, the initial degree of saturation at which the permissible
4% volumetric shrinkage occurred increased. Slag content had marginal effects on the volumetric shrinkage strain as no clear
trend was established. For each slag treatment the volumetric shrinkage strain did not vary significantly with increasing
number of drying cycles. 相似文献
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Nik Norsyahariati Nik Daud Abubakar S. Muhammed Ali M. Kundiri 《Geotechnical and Geological Engineering》2017,35(5):1967-1976
Laboratory tests were carried out on compacted granite residual soil treated with 0 to 15% Palm Oil Fuel Ash (POFA), with a view to evaluate its hydraulic conductivity for its application in landfilling. The Soil–POFA mixtures were compacted using both Standard and Modified Proctors compactive efforts at 2% dry of Optimum Moulding water Content (?2%), at Optimum Moulding water Content (0%), at 2 and 4% on the wet side of Optimum Moulding water Content (+2 and +4%). The samples were permeated with water and the effect of moulding water content; compactive effort and POFA content were examined. The samples that met the minimum threshold of 1 × 10?9 m/s were used in plotting the acceptable zones criterion at various POFA mixtures. The results gave indications of reduction in the hydraulic conductivity values, with increase in compactive efforts, moulding water content and POFA content up to about 10%. This was the most suitable soil–POFA mixture for the hydraulic application. 相似文献
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Strength properties of compacted ash layers depend to a great extent on the moulding conditions. This paper focuses on the effects of compaction energy and degree of saturation on strength characteristics of compacted pond ash. The pond ash sample, collected from the ash pond of Rourkela Steel Plant (RSP), was subjected to compactive energies varying from 357 kJ/m3 to 3488 kJ/m3. The optimum moisture content and maximum dry densities corresponding to different compactive energies were determined by conventional compaction tests. The shear strength parameters, unconfined compressive strengths (UCS) and California bearing ratio (CBR) values of specimens compacted to different dry densities and moisture content were assessed and reported. The effects of compaction energy and degree of saturation on shear strength parameters i.e. unit cohesion (cu) and angle of internal friction (Ф) values and also the UCS values are evaluated and presented herein. The results indicate that the dry density and strength of the compacted pond ash can be suitably modified by controlling the compactive energy and moulding moisture content. The strength achieved in the present study is comparable to the good quality, similar graded conventional earth materials. Hence, it may be safely concluded that pond ash can replace the natural earth materials in geotechnical constructions. 相似文献
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Effect of Soil Parameters on Dynamic Cone Penetration Indices of Laterite Sub-grade Soils from India
Varghese George Ch. Nageshwar Rao R. Shivashankar 《Geotechnical and Geological Engineering》2009,27(4):585-593
The focus of this study was on correlating the effect of grain-size, maximum dry-density (MDD), field moisture content, and
the void ratios on penetration measured using the dynamic cone penetrometer (DCP) for laterite soils blended with fines. Tests
were performed on soil samples compacted to MDD for moulding water contents set to the optimum moisture content (OMC), dry
of OMC, and wet of OMC un-soaked condition. The results indicated that an increase in the fines-content caused a decrease
in the MDD, and an increase in the OMC and the DCP penetration. Regressions were developed correlating various parameters. 相似文献
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Liang Zubing 《吉林大学学报(地球科学版)》1989,(4)
教学和科研往往需要对一些稀缺而有价值的化石标本进行复制,文中介绍了石膏模型制作过程中的备料、母模翻制和铸型的工作方法。 相似文献