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911.
912.
This paper, comparing the dynamic test results of mudstone (silty clay) with the static ones, verifies influence of cyclic loading and loading rates on the strength of mudstone. It is found that the dynamic strength is higher than the static strength. In the case of rapid loading (rising time of pressure is 10ms ), the unconfined compressive strength for this type of soil in dynamic test is 2.3 to 2.9 times as high as that in static tests, and the strength index, Cd , is about 2.8 times as great as Cs , but ∅ values are approximately equal to each other. Repeat loading (up to 3600 cycles) has no great influence on the strength of mudstone, and under the condition of unconfined loading, the fatigue strength of mudstone is somewhat lower than its statically strength. 相似文献
913.
Tang Xinbao Zhang Qinghao Zhou Yan Ma Depeng 《Geotechnical and Geological Engineering》2021,39(8):5895-5906
Geotechnical and Geological Engineering - Soft and hard rock assemblages and anchor solids have important effects on rock mechanics properties under different inclinations and assemblages, so it is... 相似文献
914.
利用磁异常模量进行磁性体边界检测 总被引:2,自引:0,他引:2
地下磁性体具有较强的剩磁或退磁会给磁异常的解释带来困难。由于磁异常模量对磁化方向不敏感,将磁异常转换为磁异常模量并用来分析和处理,可很大程度上提高磁异常解释的准确性和可靠性。本文介绍了五种磁异常模量,并且利用改进的Tilt梯度方法对各磁异常模量数据做边界检测,确定地下磁性体的水平位置。理论模型试验表明,在存在强剩磁的情况下,不同模量数据对磁性体的反应程度也不一样,运用改进的Tilt梯度方法对磁异常模量进行处理可不同程度地加强对异常体的识别,其中模量E最为准确,可较清晰地识别磁性体边界。笔者还将该方法运用到坦桑尼亚基戈马地区的航磁异常处理,并推测了该地区的构造带及磁性体边界,为深入了解基戈马成矿区带的地质和成矿背景及可能矿床分布提供了重要信息。 相似文献
915.
Xilai Zheng Junjie Zhang Tianyuan Zheng Chun Liang Hongyu Wang 《Environmental Earth Sciences》2014,71(3):1349-1356
Water content is an important physical parameter for soil, vadose zone, and porous aquifer. Accurate measurement of water content in oil-contaminated porous media is critical for the research on oil pollution process and remediation in soil and groundwater systems. In this study, an improved water content calculation formula for oil-contaminated porous media was proposed based on the theory of oven-drying method, and laboratory experiments were conducted to test the applicability and accuracy of the formula for several types of manually prepared oil-contaminated porous media with different water contents. Furthermore, the measuring method and calculation formula, which can be used to determine the water content of porous media sampled from the oil-contaminated sites, were proposed for the first time in this study based on the improved formula. The experimental results showed that the improved formula was very accurate when used to calculate the water contents of diesel-contaminated sand, gasoline-contaminated mild clay, and engine oil-contaminated sand, indicating that it was widely applicable to oils with different volatile ability as well as porous media with different texture. This study meets the urgent need for accurate determination of water content in oil-contaminated porous media, and it solves the technical problem that the existing water content measuring methods cannot be applied directly in the field study. 相似文献
916.
917.
918.
以山东三山岛仓上金矿露天坑尾矿库为研究对象,在高陡岩质边坡CSMR评分基础上,通过岩石力学饱水实验,对岩石力学参数进行弱化,对尾矿库边坡四个典型剖面处边坡在无水、-100m水位、-50m水位和-40m水位下的CSMR动态评分,将487和503剖面动态CSMR评分与矿坑库水位之间的关系进行指数函数拟合,研究其评分和矿坑库水位之间的动态关系。结果表明:边坡RMR值降低,直接致使CSMR值的降低;487和503剖面的CSMR评分相较于483和507对于水位的上升更为敏感,且487和503剖面在水位的上升过程中,CSMR评分率先跌破40分,使边坡处于不稳定状态;库水位在-48.302m时,边坡487和503剖面发生小规模滑动,与CSMR评分结果一致;边坡在当前-47.643m库水位工况下具有一定的安全性,并据此推算边坡的临界库水位在-42.37m~-40.62m之间。通过对露天矿坑库水位临界值的研究,为矿坑边坡的安全稳定性提供有力依据。 相似文献
919.
在分析戈壁沙漠地区地球物理特征的基础上,针对性的提出了解决煤田地质构造问题的方法,包括三维地震野外施工方法的选取、施工因素的选择、资料处理手段;并以获得的实际地质成果证实三维地震在解决复杂地质构造问题的可行性。 相似文献
920.
Xia Wenchen Zhou Jie Lei Jianxi Zhang Nianmao Peng YangChina U niversity of Geoscience W uhan Hubei Wang Yujun 《《地质学报》英文版》1995,69(4):341-357
On the basis of exhaustive researches on the facies sequences and depositlonal evolutionary process of various depositional systems, the genetic stratigraphic framework of the extensional rifted oceanic basin, which has undergone strong structural destruction, has been reconstructed by means of dynamic genetic stratigraphic analysis. Five depositional episodes have been distinguished from various isochronous stratigraphic boundaries and stratigraphic sequences with the three-dimensional structure of each depositional episode analysed in detail. The tectonic paleogeographic environment corresponding to different stages of each depositional episode has been reconstructed for individual depositional system tracts. And the evolution history of this rifted basin has been divided into four stages' initial rifting and oceanization of continental crust, stretching and spreading of the basin, subduction and basin differentiation, and convergence and collision. A NNE-trending intracontinental soft collision sutur 相似文献