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261.
四川省青川县东河口滑坡岩石的抗剪断性质试验 总被引:1,自引:0,他引:1
东河口滑坡是5·12汶川大地震触发的典型的高速远程滑坡,致使780余人遇难。该滑坡体主要由震旦系灰岩和寒武系炭质板岩、千枚岩构成。震后在对该滑坡进行详细野外调研的基础上,采集了具有代表性的岩块作为试验样品,利用60t液压式万能材料试验机对该滑坡岩石的抗剪断性质进行了一系列试验。试验结果表明,水对该滑坡岩体的力学性质有重要的影响,干燥状态与饱水状态下岩石的抗剪断强度有很大的差异,岩石中存在的结构面也是影响岩石力学性质的主要因素之一,是岩质边坡稳定性的一个主要控制条件。 相似文献
262.
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264.
分析了淮北新矿区新生界底部松散层沉积物沉积特征及水理性质,尤其是四含的岩性组合结构。在对各级粒径之间的相互掺杂进行统计的同时,对岩层的厚度,物理性质,水理性质,矿物形态及含量进行进一步的研究。得出结论:淮北煤田新矿区松散沉积物第四含水层是以下部合粘性土砂砾层和上部夹砂层的粘性土段组成。分布较稳定,但厚度和岩性有较大变化,主要受古地形和古地理位置的控制。各种粒级的沉积物相互掺杂,颗粒分布不均一,砂性土的有效粒径与其本身定名粒级相比低2~3个粒级,其透水性与比其低2个粒级沉积物相当。四含不仅具有隔水性,而且有较强的持水性。 相似文献
265.
通过成岩作用及储层物性的综合分析,该区主要油层组长9、长8、长6及长2的岩石成分成熟度和结构成熟度均较差,均经历了晚成岩A期。压实作用降低了储层的孔隙度,致密的碳酸盐岩胶结降低了孔隙度并阻止了次生孔隙的产生。该区储层为低孔低渗储层,孔隙度在4%-8%之间,渗透率多小于0.1×10^-3μm2。 相似文献
266.
Application of 3-D Geoscience Modeling Technology for the Estimation of Solid Mineral Reserves 总被引:1,自引:0,他引:1
Abstract: Applying new approaches, methods, and technologies for the estimation of reserves can effectively improve the efficiency and accuracy of assessments of solid mineral resources. After analyzing the development of 3-D geoscience modeling technology (3-D GMT), this paper discusses the application of 3-D GMT for the estimation of solid mineral reserves, emphatically introducing its workflow and two key technologies, 3-D orebody surface modeling, and property modeling. Moreover, the paper analyzes the limitations of traditional methods, such as the section method and geological block method, and points out the advantages of 3-D GMT: building more accurate 3-D orebody models, expressing the internal inhomogeneous attributes of an orebody, reducing the potential for errors in the estimation of reserves, and implementing dynamic estimations of reserves. 相似文献
267.
This study examines the challenges of achieving sustainable management of the world's largest mangrove forest, the Sundarbans, in Bangladesh. The Sundarbans is currently managed by the Bangladesh Department of Forest, under a state property‐rights regime, while our study explores an alternative property‐rights regime. We employed a mixed‐method approach to examine the prospects of alternative management and livelihood strategies to achieve sustainability. Both focus groups and household surveying were used to assess the opportunities for, and barriers to, achieving sustainability. It was found that two conflicting groups—forest‐dependent communities and foresters—are responsible for policy failures due to the absence of power‐sharing arrangements, nor is it likely a common property‐rights regime will be enough to cap degradation and achieve sustainability, while supply‐and‐demand policy interventions may well could help achieve sustainable management of the Sundarbans. 相似文献
268.
《The Professional geographer》2013,65(4):449-464
During the late 1980s some informal settlements were established within or near affluent Cape Town suburbs. Despite objections by suburban residents that these settlements would lead to a rapid escalation in crime and a dramatic fall in the value of properties, the authorities allowed the settlements to remain. Using data on property transfers, which are then mapped using GIS, the paper examines the effects that the informal settlement of Marconi Beam had on house prices and housing turnover within the adjacent suburb of Milnerton. The results show that most of the objections regarding Marconi Beam's effect on property values were groundless as the settlement had only a negligible effect on property values in the adjacent suburb. 相似文献
269.
Crushed rock subgrade, as one of the roadbed-cooling methods, has been widely used in the Qinghai-Tibet Railway. Much
attention has been paid on the cooling effect of crushed rock; however, the mechanical properties of crushed rock are
somehow neglected. Based on the discrete element method, biaxial compression test condition for crushed rock is compiled
in FISH language in PFC2D, and the natural shape of crushed rock is simulated with super particle "cluster". The effect
of particle size, crushed rock strength and confining pressure level on overall mechanical properties of the crushed
rock aggregate are respectively analyzed. Results show that crushed rock of large particle size plays an essential framework
role, which is mainly responsible for the deformation of crushed rock aggregate. The strength of gravel has a great
influence on overall mechanical properties which means that strength attenuation caused by the freeze thaw cycles cannot
be ignored. The stress-strain curves can be divided into two stages including shear contraction and shear expansion at
different confining pressures. 相似文献
270.
宋军 《测绘与空间地理信息》2013,(8):210-211,213
以竣工前后的房产面积差异分析为研究对象,从计算规则改变、设计变更、施工变更等五个方面分析了其中原因,全文是笔者长期工作实践基础上的理论升华,相信对从事相关工作的同行能有所裨益。 相似文献