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31.
In terms of the Muruntau open pit, the paper addresses the possibility of formation of a rupture structure in host rock, based on the analysis of its surface manifestations. __________ Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 1, pp. 80–89, January–February, 2008.  相似文献   
32.
The prototype of a new portable device of EMRR series (electromagnetic radiation recorder), EMRR-3 is developed and manufactured to monitor and forecast dynamic rock mass manifestations by electromagnetic radiation signals. The device makes it possible to predict dynamic manifestations based on algorithms of stable electromagnetic signal detection, to perform long-term (up to 8 h) digital recording of electromagnetic situation in underground mine workings, followed by the accumulated information computer-processing. __________ Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 2, pp. 115–122, March–April, 2008.  相似文献   
33.
中国天然石材放射性水平及影响因素   总被引:12,自引:0,他引:12  
本文通过国产102个石材品种186个样品实测数据的统计分析,得出大理石(3个品种、各1个样品)、板石(1个品种、1个样品)中^226Ra、^222Th和^40K的放射性平均比活度分别为25.2/10.6,11.9/4.2和105/241Ba/kg。而酸性花岗岩(71个品种、138个样品)和碱性花岗岩(2个品种、7个样品)放射性水平较高,其^226Ra、^232Th和^40K的平均比活度分别为79.6/126.9,99.9/158.9和1128/2920Bg/kg。影响天然石材放射性水平的因素主要是石材矿床的岩性,其次是蚀变、地质年代、岩相及岩带等。  相似文献   
34.
Deeply weathered lava flows of oceanic basalt reflect the mode and sequence of volcanic deposition, parent mineralogy, and postdepositional erosional and weathering processes. In turn, these are controlled by geology, geography, and climate. One particular site on the Island of Hawaii has been the focus of study to gain a better understanding of complex residual soil deposits, particularly in connection with a need to characterize seismic strong-motion propagation through decomposed surface soil and rock sequences. Materials at the site range from fully weathered volcanic soils, sometimes with unusual mineralogy and plasticity properties, to saprolite, weathered rock, vesicular basalt, and hard rock. Seismic surveys were conducted to investigate the distribution of these materials at the study site. Laboratory tests focused on saprolite and vesicular rock as two materials that are seldom reported on and that remain poorly characterized, at least with regard to conditions found in Hawaii.  相似文献   
35.
江苏栖霞山铅锌银多金属矿床成矿时代探讨(增刊)   总被引:2,自引:0,他引:2  
江苏栖霞山铅锌银多金属矿床是长江中下游铁、铜、铅锌、金多金属成矿带宁镇矿集区规模最大的铅锌多金属矿床。自发现铅锌矿以来,众多地质工作者针对栖霞山铅锌银多金属矿床的勘探和综合研究做了大量的工作,但由于在矿区范围内尚未发现与成矿相关的岩体,且缺乏适合于传统同位素定年方法的矿物,因此尚无法确定该矿床具体的成矿时代。本文基于矿床地质特征、区域成矿规律及矿床构造控矿规律的综合对比研究,初步认为栖霞山铅锌银多金属矿床成岩与成矿作用是与宁镇地区燕山晚期主要中酸性侵入岩形成时间同期连续发生的,大致推断其成矿作用应发生在110~100Ma左右,属早白垩世晚期产物。  相似文献   
36.
Mass Angle of Repose of Open-Graded Rock Riprap   总被引:1,自引:0,他引:1  
Mass angle of repose (that is, the angle at which a mass of sliding particles will come to rest) is a fundamental material property that is needed to design drainage channel linings composed of open-graded riprap stone, also called dumped rock riprap, which protect earthen slopes from erosion by flowing water. Multiple regression analysis of measurements at 74 stockpiles of dumped natural and crushed rock shows the angle to depend primarily on rock particle angularity and, to lesser extents, on the gradation and the median particle diameter of the stone mixture, the angle increasing with angularity, mixture nonuniformity, and particle size. Uncomplicated expressions are developed from the data to calculate the expected mass angle of repose of open-graded rock riprap along with prediction intervals.  相似文献   
37.
高性能计算是实现大规模并行计算的有效途径,本文论述了如何构建一个高性能集群,介绍了集群安装工具--Rocks,分析Rocks安装机制、特点以及Rocks如何管理集群,利用Rocks搭建了一个基于Linux的高性能集群平台,并在该平台上实现了量子化学软件Gaussian的应用,进一步测试了Rocks系统的性能。  相似文献   
38.
混凝土、岩石类损伤材料宏观断裂模型及应用   总被引:3,自引:1,他引:2  
本文研究了混凝土、岩石类损伤材料的宏观断裂模型。文中从损伤材料中微裂纹等缺陷的拉裂扩展过程,研究宏观断裂的形成与发展,并由此建立了相应的本构关系和断裂判据。文中对此模型用地质力学模型试验作了验证。最后将其应用于某水电站建基面外移方案可行性研究中。  相似文献   
39.
This paper discusses the identification of poroelastic constants and hydraulic conductivity from two transient laboratory tests performed on cylindrical core: drained isotropic confinement and pulse test. The combination of the two tests allows us to estimate all poroelastic parameters with the exception of the shear modulus. Despite the lack of analytical solutions for the fully coupled case, closed form solutions of the forward problems are obtained for a slender specimen. The validity of these solutions for a realistic aspect ratio of the core is assessed by a comparison with a finite element model. The identification problem is solved by minimizing a least square functional using an explicit gradient computed using the direct differentiation of the closed form solution and a Levenberg–Marquardt algorithm. The uniqueness of this inverse problem as well as the effect of noise on input data are fully discussed. The identification procedure is then applied to tests performed on a deep argillaceous rock (argillite of Meuse Haute–Marne).  相似文献   
40.
1 Introduction Naturally occurring radionuclides 226Ra, 232Th and 40K are widespread in the earth’s environment and they exist in various geological formation such as soil, rock, water and plants [1]. These radionuclides pose exposure risks externally due to their γ-ray emissions and internally due to radon and its progeny, which emit alpha particles. Even though these radionuclides are widely distributed, their concentrations have been found to depend on the local geological condition and …  相似文献   
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