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1.
The accuracy and reliability of the determination of the solid-phase density (SPD) for disperse soils by the standard method (State Standard 5180-84) and by the Kalachev rapid method were estimated. The causes for discrepancies in the SPD determination in clay soils between the two different methods were determined for the cases of similar and different preanalysis preparations. A justified calculation procedure for the determination of the bound-water density in clay soils, which is adequate for the nature of complex physical phenomenon, was developed. Corrections for the bound-water density in clay polymineral soils with different dispersion properties are suggested.  相似文献   

2.
The International Association of Geoanalysts (IAG) has certified a slate sample, OU-6, for twelve major and minor constituents, as well as thirty-five trace elements through an interlaboratory programme conducted in close compliance with the International Organization for Standardization (ISO) Guide 35 (1989). Laboratories were qualified for participation in the certification programme, based on their performance in the prior analysis of OU-6 as a proficiency test material. Thirty laboratories provided data for the certification, though not for each constituent that was certified. Certification criteria included a means of establishing traceability for the certification data, generally through concurrent analysis of the existing Geological Survey of Japan reference material JSl-1, agreement of results between laboratories and methods, and a minimum of data rejection (4% rejection rate for OU-6 data and 6% for JSl-1 data), preferably for well-understood technical reasons only. Information values are provided for an additional eight constituents where certification criteria were not met. Uncertainties developed in accordance with the "Guide on Uncertainty in Measurement" (Eurachem 2000) and representing the 95% confidence interval of the certified and information values are reported for all fifty five constituents. The material is currently available in 40 g units for distribution by the IAG. Supply is anticipated to last about ten years.  相似文献   

3.
土体导热系数的评价与计算   总被引:23,自引:5,他引:18  
刘为民  何平  张钊 《冰川冻土》2002,24(6):770-773
土体的导热系数是土木工程热工计算的重要参数.土体的多孔介质性质决定了土体的导热性质与干土、气体及孔隙充填物(水)的含量有密切关系.实验测试结果表明,土体不论处于冻结还是融化状态,其导热系数均随干容重以及含水量的增加而增大.采用土体的物理性质指标,对土体的导热系数进行了分析,给出土体导热系数较为方便的计算方法,有利于工程设计计算参数的选取,同时与实验测试结果对比,有较好的吻合度.  相似文献   

4.
High-resolution space-borne remote sensing data are investigated for their potential to extract relevant parameters for a vulnerability analysis of buildings in European countries. For an evaluation of large earthquake scenarios, the number of parameters in models for vulnerability is reduced to a minimum of relevant information such as the type of building (age, material, number of storeys) and the geological and spatial context. Building-related parameters can be derived from remote sensing data either directly (e.g. height) or indirectly based on the recognition of the urban structure type in which the buildings are located. With the potential of a fully- or semi-automatic inventory of the buildings and their parameters, high-resolution satellite data and techniques for their processing are a useful supporting tool for the assessment of vulnerability.  相似文献   

5.
现行《岩土工程勘察规范》是岩土工程勘察行业最具有强制性、权威性、约束性的国家技术标准。根据大量的工作实践和交流、对比、分析,对《岩土工程勘察规范》的适用范围、岩石质量指标、地震效应、水土腐蚀性判别等部分条款的规定和实践中操作的可行性作一交流,供同行讨论,也供国标再修订、编写时参考。  相似文献   

6.
Some models for the rate of crystallization of garnet in metamorphic rocks   总被引:1,自引:0,他引:1  
Ralph Kretz 《Lithos》1974,7(3):123-131
Information on the form of the equation for the rate of crystallization of garnet in metamorphic rocks may be obtained by combining an expression for the rate of crystal growth, obtained from data on compositional zoning, with an expression for the rate of nucleation, obtained from the crystal-size distribution.Three models for the rate of crystal growth and four for the rate of nucleation are formulated, and these, in different combinations, give rise to ten models for the rate of crystallization. Considerable variation in the form of the growth and nucleation equations produces a relatively small variation in the form of the equation for the rate of crystallization. In the favoured crystallization models, the volume of garnet produced in unit volume of rock is a function of time raised to the power m, where m lies between 3.5 and 5.  相似文献   

7.
黑河中游灌区地下水位短期季节性变化趋势预测   总被引:3,自引:1,他引:3  
利用黑河中游平川、板桥、鸭暖和蓼泉灌区8眼观测井的1985-2002年逐月实测平均地下水位埋深资料(共1728个月),基于帕森斯季节性指数理论,分别建立了黑河中游灌区具有代表性的平川、板桥、鸭暖、蓼泉四灌区共8眼观测井季节地下水位埋深动态变化预测模型,并用2003年各观测井的资料进行了趋势预测进行检验.结果表明:观测井地下水位变化过程呈线性递减的相关系数越显著,其拟合误差和预测误差越小.各观测井地下水位帕森斯季节性指数模型拟合差≤0.05 m的月数占总检验月数的比例平均为38.33%,拟合差≤0.10 m的月数占总检验月数的比例平均为72.50%,>0.25 m的月数占总检验月数的比例平均为2.00%;各观测井预测误差≤0.05 m的月数占总预报月数的比例平均为36.46%,预测误差≤0.10 m的月数占总预报月数的比例平均为64.38%,>0.25 m的平均比例仅为2.00%,说明帕森斯季节性指数模型可以对短期黑河中游典型灌区地下水位动态趋势进行预测.  相似文献   

8.
On paleoclimatic-geological premises and by available indications in the field, prospecting for bauxites of the platformal type is recommended in certain Siberian districts in which conditions were favorable for bauxitization at the end of the Triassic, in the Barremian-Aptian, the Turonian, and the Eocene. -- V.P. Sokoloff.  相似文献   

9.
青海那陵郭勒河东晚三叠世侵入岩形成环境及年代学研究   总被引:5,自引:0,他引:5  
那陵郭勒河东晚三叠世侵入岩是本区众多矽卡岩型铁矿产的成矿母岩,利用Maniarand Piccoli(1989)提出的五组图解判别构造环境方法,判定其为后造山花岗岩类(POG型),与区域资料吻合。利用U—Pb法测年结果,表明其侵位时代在(214.2±1.3)~(225.2±1.2)Ma,是印支晚期岩浆活动的产物。对其进行岩石学成因和侵位时代研究,为东昆仑华力西一印支造山旋回在晚三叠世晚期进人造山带伸展崩塌提供同位素年代制约,并为研究该区矿产成矿地质背景及今后寻找矿产资源提供指导意义。  相似文献   

10.
尾矿坝渗透静力稳定分析   总被引:8,自引:2,他引:6  
边坡稳定的条分法中,条间剪切力的作用效应根据分析方法的不同,对稳定系数的计算结果存在较大的差异。有效应力分析方法中依据渗流场的计算分析得到条间孔隙水压力。基于Bishop条间力的假定原理,提出一种新的条间孔隙水压力的分析方法,以确定边坡的最小稳定系数。实际工程计算反映出不同计算方法的差异及新方法的实用性。  相似文献   

11.
松辽盆地营城组火山机构类型划分为碎屑岩火山机构、熔岩火山机构和复合火山机构3种。碎屑岩火山机构中火山通道相占9.3%,爆发相占55.3%,喷溢相占29.2%,侵出相占1.4%,火山沉积相占4.8%;火山机构半径为0.5~1.5 km,高度为50~220 m。熔岩火山机构中火山通道相占8.1%,爆发相占23.4%,喷溢相占62.6%,侵出相占5.1%,火山沉积相占0.8%;火山机构半径为1~2 km,高度为200~300 m。复合火山机构中火山通道相占4.9%,爆发相占34.4%,喷溢相占56.8%,侵出相占2.6%,火山沉积相占1.3%;火山机构半径为2~4 km,厚度为300~450 m。亚相控制储层流动单元的规模,碎屑岩火山机构的储层流动单元范围为0.3~1.5 km,厚度小于60 m。熔岩火山机构的储层流动单元范围为1~2 km,厚度小于80 m。复合火山机构的储层流动单元范围为1.5~3.0 km,厚度小于100 m。各类火山机构气藏开发时的井距和压裂方案均存在差异。  相似文献   

12.
Statistics of ultimate strain are improved by adding new data to the previous ones. The critical value for horizontal strain seems somewhat larger than that for vertical strain, although parameters of a Weibull distribution, which is customarily used for quality-control research and which fits in very well with the present statistics, are calculated for the whole set of data making no distinction between the two subsets because of their scantiness.On the basis of the parameters thus determined and strain rates obtained from geodetic data, probabilities of earthquake occurrence in a few regions in Japan and the U.S. are estimated. Probability of having an earthquake in an area southwest of Tokyo, where we had the 1923 earthquake (magnitude 7.9), at this time amounts to 20%, a value almost the same as that obtained in the previous papers. The probability will reach some 50 and 90% by 2000 and 2050, respectively. In the North Izu district, where an earthquake of magnitude 7.0 occurred in 1930, a shearing crustal motion is going on to an extent for which we have a probability for an earthquake recurring there in these 40 years amounting to 40%. By the end of this century, it will become as high as 85%.Similar estimates of such cumulative probabilities are made for the San Francisco and Fort Tejon regions, where great earthquakes occurred respectively in 1906 and 1857, yielding values of 30 and 80% at present. These probabilities are tentative because of possible errors in evaluating geodetic measurements and uncertainty of the ultimate crustal strain assigned to the San Andreas fault.  相似文献   

13.
The amplification coefficient for gravitational lensing of a point source in the linear-caustic approximation is compared with exact values calculated for a lens comprised of two point masses. Even in the most favorable case for the caustic crossing, the error in the amplification coefficient remains below 1% only for distances to the caustic not exceeding 0.01 of the Einstein radius.  相似文献   

14.
流体包裹体气液成分原位测定的新进展   总被引:4,自引:1,他引:3  
李淑玲 《岩矿测试》1999,18(1):72-76
综述了近年来流体包裹体原位测定的分析方法,其中较为常用的方法为激光拉曼光谱法,质子探针法等。激光烧蚀法是最近发展起来的一种打开单个包裹体的新方法。该方法与其它技术相结合对测定流体包裹有一定的发展前景。  相似文献   

15.
土体应力-应变关系转型问题分析   总被引:14,自引:2,他引:12  
王成华  李广信 《岩土力学》2004,25(8):1185-1190
通过对土体应力应变试验结果的分析,明确指出了土体普遍存在的应力-应变关系转型现象。提出了按后破坏模量和临界围压两个参数判别土体应力-应变关系转型的方法,对影响土体应力-应变关系转型的因素包括土的类型、围压、初始密度或含水率、排水条件及应力路径等进行了简要分析。最后,对砂土初步提出了一个能反映转型现象的组合应力-应变关系模型的理论框架。  相似文献   

16.
The results of calculation of the seismic moment tensor (in the double-couple approximation) for the earthquake that occurred in the northeastern Taimyr Peninsula on June 9, 1990, from amplitude spectra of the surface waves, are presented. The obtained results are of interest for works related to construction of geodynamic models for the Taimyr region, for studies of the stress-strain state of the Earth’s crust, and for assessments of the seismic hazard of this territory.  相似文献   

17.
One of the major causes for concern in the landfilling of heavy metal sludges is the potential for acid leaching. In this paper the CHEMFIX waste-form is described, which, because of its low permeability, high buffer capacity against acid leaching and its claylike structure and properties, can be used to stabilise heavy metal sludges for landfilling.

A simple model is developed and used to investigate the values of the various parameters involved in the product design. It is shown that for barrier lifetimes orders of magnitude in excess of those expected for conventional cut-off walls and liners should be possible.  相似文献   


18.
可压性是衡量页岩气储层对压裂改造响应程度的重要依据,目前针对页岩可压性常用脆性指数对其进行评价。但在实际运用中存在脆性指数相近,实际压裂效果却差别甚远的问题。为了弥补利用脆性指数进行页岩气储层可压性评价的不足,在考虑断裂韧性影响的基础上引入临界机械能释放率,综合了Ⅰ型、Ⅱ型断裂韧性对岩石裂缝发育的影响,并定义平均临界机械能释放率。最后结合平均临界机械能释放率和脆性指数,初步建立了以裂缝发育指数为量化指标的页岩气储层可压性评价模型。基于焦石坝龙马溪组焦页48-2HF井测井资料,计算出其弹性模量、泊松比、Ⅰ型及Ⅱ型断裂韧性,并根据构建的裂缝发育指数模型,得出页岩储层可压性随埋深的变化关系。结合现场微震资料,验证了该模型能有效预测页岩气储层可压性随埋深的变化趋势,为页岩气实际开发过程中优选页岩储层压裂段提供可靠方法。   相似文献   

19.
A scheme for the spatial distribution of ground successions in the territory of Russia is constructed. Peculiarities of the ground composition and structure in the section of the succession, the character of the state of ground successions caused by the phase state of water in the successions, annual mean temperatures and degree of humidity for thawed and non-frozen rocks, as well as the degree of ice content for permafrost rocks, were used as qualification indicators. The variety of recognized ground successions, which differ in their genesis and specific features of structure, composition, and state, are demonstrated. Patterns of their distribution are discussed.  相似文献   

20.
孙培德 《岩土力学》2005,26(Z2):222-226
根据地温场温度分布的数学模型,应用有限元法模拟了深井巷道围岩地温场中4种常见隧道断面的岩石温度分布特征规律,揭示出地温场内温度分布和地热学参数及时间、空间之间的本质关系,实现地温场内温度分布的二维动态等值线表征,直观地再现了地温场内温度分布非稳态变化的动态过程。  相似文献   

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