共查询到18条相似文献，搜索用时 593 毫秒
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目前国内外对工程岩体完整性的评价方法很多,均从某一侧面间接反映了岩体的完整程度,缺乏科学性.结合工程勘察实践及相关学科的研究,对岩体完整性评价,建立了KY、RID新公式,提高了工程岩体完整程度评价方法的科学性. 相似文献
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布谷马西钾盐矿区位于刚果共和国奎卢省黑角市北约30 km处。根据矿层分布情况,以奎卢河为界将该矿区划分为南、北2个矿段。南部矿段钾盐矿层厚度大,分布连续,有益组分含量较高,现已进行了详查。矿层埋藏较深,上部盐岩层完整性好,下部盐岩层多发育Ⅳ级结构面,完整性不均一,工程地质条件程度为复杂。经综合分析竖井宜建在比利村及向南2 km的ZK201孔附近,该区岩层稳定,岩体完整程度高,构造相对不发育,建井时要注意岩体完整性差部位的浇铸支护,以防发生坍塌、突水等不良地质现象。 相似文献
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对三峡水网的6口观测井的温度梯度测量结果表明:太阳辐射热的影响深度为20～30 m;各井的水温梯度差异较大,同一井不同深度井段的温度梯度也不同。影响温度梯度的主要因素是地层岩性、岩体发育的完整性和太阳辐射热。 相似文献
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大柳树坝址区松动岩体中硐室围岩破坏变形特征 总被引：2，自引：0，他引：2
以黄河大柳树坝址为例,对松动岩体硐室围岩破坏变形特征进行了研究,松动岩体具有断裂张开、节理错动、岩体架空、岩石高强度、岩体波速等特征。研究得出松动岩体硐室围岩破坏变形特征为结构松散、塌落范围大、变形破坏受水影响大及围岩压力以重力为主等特点。 相似文献
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文章为精准测定横州新村岩体的形成年代、岩浆源区性质、侵入年代及成因构造环境,对横州新村岩体的侵入地质环境、岩石地球化学及LA-ICP-MS锆石U-Pb同位素年龄等进行分析,获得横州新村岩体最后的成岩年龄为(246.6±0.54)Ma,平均年龄为(246.5±1.0)Ma,确定横州新村岩体侵入年代为印支期中三叠世产物,属... 相似文献
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田志永 《地球科学与环境学报》1993,(4)
本文对甘肃北山南带拾金坡岩体地质、岩石学、岩石化学、稀土元素、稳定同位素及同位素年代学等方面作了较系统的研究,认定该岩体属加里东晚期以陆壳改造为主的多成因复式岩体。对副矿物磁铁矿含金性的研究,推断岩体成岩时原始含金丰度较高。海西早期岩体发生了较强烈的钾交代作用,“酸碱分离”形成了含金石英脉型矿化。 相似文献
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Weak rock zone (soft interlayer, fault zone and soft rock) is the highlight of large-scale geological engineering research.
It is an important boundary for analysis of rock mass stability. Weak rock zone has been formed in a long geological period,
and in this period, various rocks have undergone long-term consolidation of geostatic stress and tectonic stress; therefore,
under in-situ conditions, their density and modulus of deformation are relatively high. Due to its fragmentary nature, once
being exposed to the earth’s surface, the structure of weak rock zone will soon be loosened, its density will be reduced,
and its modulus of deformation will also be reduced significantly. Generally, weak rock zone can be found in large construction
projects, especially in the dam foundation rocks of hydropower stations. These rocks cannot be eliminated completely by excavation.
Furthermore, all tests nowadays are carried out after the exposure of weak rock zone, modulus of deformation under in-situ
conditions cannot be revealed. In this paper, a test method explored by the authors has been introduced. This method is a
whole multilayered medium deformation method. It is unnecessary to eliminate the relatively complete rocks covering on weak
rock zone. A theoretical formula to obtain the modulus of deformation in various mediums has also been introduced. On-site
comparative trials and indoor deformation modulus tests under equivalent density conditions have been carried out. We adopted
several methods for the prediction researches of the deformation modulus of weak rock zone under in-situ conditions, and revealed
a fact that under in-situ conditions, the deformation modulus of weak rock zone are several times higher than the test results
obtained after the exposure. In a perspective of geological engineering, the research findings have fundamentally changed
peoples’ concepts on the deformation modulus of weak rock zone, provided important theories and methods for precise definition
of deformation modulus of deep weak rock zone under cap rock conditions, as well as for reasonable engineering applications. 相似文献
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A modified Hoek-Brown failure criterion considering the damage to reservoir bank slope rocks under water saturation-dehydration circulation 总被引：1，自引：0，他引：1
After water is impounded in a reservoir, rock mass in the hydro-fluctuation belt of the reservoir bank slope is subject to water saturationdehydration circulation (WSDC). To quantify the rate of change of rock mechanical properties, samples from the Longtan dam area were measured with uniaxial compression tests after different numbers (1, 5, 10, 15, and 20) of simulated WSDC cycles. Based on the curves derived from these tests, a modified Hoek- Brown failure criterion was proposed, in which a new parameter was introduced to model the cumulative damage to rocks after WSDC. A case of an engineering application was analyzed, and the results showed that the modified Hoek-Brown failure criterion is useful. Under similar WSDC-influenced engineering and geological conditions, rock mass strength parameters required for analysis and evaluation of rock slope stability can be estimated according to this modified Hoek-Brown failure criterion. 相似文献
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岩体变形和破坏可以看作能量耗散和释放的过程.由于节理岩体结构复杂且难以开展室内试验,因此无法通过试验直接求取其能量学参数.基于Hoek-Brown准则和岩石能量理论,提出了节理岩体在临界状态能量学参数的估算方法.针对含贯通节理(或层面)岩体,通过修正岩块单轴抗压强度以体现贯通节理的方向效应.采用PFC3D分别模拟小尺寸岩样(Φ50mm×100mm)和大尺寸岩体(Φ2m×2m)的三轴压缩试验,通过岩石三轴试验结果拟合岩石数值模拟的细观参数并应用于节理岩体的模拟.根据节理岩体模拟得到应力应变曲线和能量流,验证了Hoek-Brown准则对节理岩体能量参数估算的合理性. 相似文献
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碱性岩及其相关的金矿研究已成为一个新的研究热点。通过对国内外碱性岩及与其相关的金矿特征的总结，并与辽宁碱性岩及其相关的金矿对比，发现本地区碱性岩金矿化率较高，尤其是碱性侵出（入）岩比其它任何岩类的成矿率都要高。大石沟、南大线和东五家子、长皋、线金厂等金矿床是典型的与碱性岩有关的金矿床，前二个金矿床与早白垩世晚期破火山口构造、末期次火山侵出相粗面岩有关，后三者与中生代脉状侵入的煌斑岩脉有关。另外还有与正长岩、霓辉岩有关的金矿点。辽宁与碱性岩相关的矿床形成时代晚于碱性岩，主要为浅成热液型金矿床，矿化类型以脉状为主，或为含金构造蚀变岩，或为含金石英脉，矿种以金为主，多伴生银和铜，矿床形成温度以中低温为主。有些金矿点金品位较高，具有一定的矿化规模，附近有金的重砂和化探异常显示，成矿条件有利，找矿前景很好，甚至是极有可能获得突破的重要靶区。建议对于这类成矿预测区予以特别注意。 相似文献
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Qingchengzi ore concentration area in Liao-Ji rift is an important lead-zinc ore area of China,and the deep prospecting in this area has great prospects.Based on the spatial occurrence of ore bodies the Pb-Zn deposit can be divided into three types:layered,vein-shaped and pinnate.The deep geological conditions in this area are deduced by analyzing the tectonic evolution process and rock mass gravity inversion.The tectonic evolution of Liao-Ji rift can be divided into three stages:Paleoproterozoic extension period,Mesoproterozoic compression period and Mesozoic reactivation period.The magmatic activities in the Indosinian epoch led to the distribution pattern of the present deposits.According to the gravity inversion,Shuangdinggou-and Xinling rock masses on the north and south sides of the mining area are connected in the deep.The connected rock body might be distributed in the entire mining area.Xinling rock mass may be a branch extending from Shuangdinggou rock mass along the northeast trending fault,the connected rocks provide magmatic hydrothermal fluid for the final,folds and faults result in different types of ore body shapes. 相似文献