结构面对程潮铁矿东区地表及岩体移动变形的影响研究   总被引：2，自引：0，他引：2  

席人双  陈从新  肖国锋  黄平路 《岩土力学》2011,32(Z2):532-538

以程潮铁矿东区为例,通过现场结构面调查、地表及深部岩体变形监测,分析了该区地表及岩体移动变形与结构面的关系。结果表明：程潮铁矿东区地表及岩体移动变形主要受该区复杂的地质条件控制,特别是结构面的影响,变形方向和变形量值均与理论预期不同。NNE、NE向结构面的存在控制着岩体向采空区运动的侧向边界条件,同时导致变形方向的向西偏转,NWW向结构面的松动导致东主井区岩体向采空区的倾倒变形,地表变形在南北剖面上呈三级阶梯分布;西风井相对东西采空区的特殊位置以及NE向结构面的影响使其变形值小于预期,是该区相对安全的主要原因。  相似文献   

多参数岩体结构面优势分组方法研究   总被引：2，自引：0，他引：2  

徐黎明  陈剑平  王清 《岩土力学》2013,34(1):189-195

在岩体力学和水力学分析中,搞清岩体结构面的分布规律是一项重要的基础工作。当岩体结构面的产状一致,而其他性质不一致时,岩体结构面的力学和水力学性质是不同的,而传统的方法仅根据岩体结构面的产状进行分组,这势必存在缺陷。提出了一种基于变尺度混沌优化算法的多参数结构面数据的优势组划分方法,通过度量结构面之间的相似性建立目标函数,运用变尺度混沌优化算法搜索目标函数的最优解来确定聚类中心,可同时考虑结构面的多个参数,把具有相似性质的结构面归并成组。通过计算机模拟的结构面数据验证了此算法的正确性,最后将此算法应用于实际工程中测量的多参数结构面数据的优势组划分,得到了清晰可靠的分组结果。  相似文献   

A note on the effects of material discontinuities on spatial variations of surface displacements from static dislocations     

《Soil Dynamics and Earthquake Engineering》2014

Post-earthquake observations show that permanent static and transient dynamic displacements in the near field of shallow faults can be complex and quite different from theoretical predictions for homogeneous half-space. These complexities are associated with many departures from the linear, elastic, homogeneous, and isotropic representations, and include the consequences of complex three-dimensional (3D) geology surrounding faults. In this paper we illustrate these complexities for a two-dimensional (2D) model of shallow strike-slip fault when it is inside, on the border, and outside a sedimentary basin.  相似文献   

Topography of the Moho and Conrad discontinuities in the Kyushu district,Southwest Japan     

Hitoshi Oda  Takashi Ushio 《Journal of Seismology》2007,11(2):221-233

The first P-arrival time data from local earthquakes are inverted for two-dimensional variation of the depths to the Conrad and Moho discontinuities in the Kyushu district, southwest Japan. At the same time, earthquake hypocenters and station corrections are determined from the data. The depths to the discontinuities are estimated by minimizing the travel time residuals of first P-arrival phases for 608 earthquakes observed at 57 seismic stations. In the land area of Kyushu, the Conrad and Moho discontinuities are located within the depth ranges of 16–18 and 34–40 km, respectively. The Conrad discontinuity is not as largely undulated as the Moho discontinuity. The depth to the Moho is deep along the east coast of Kyushu, and the deepest Moho is closely related to markedly low velocity of P wave. We regard the deepest Moho as reflecting the Kyushu–Palau ridge subducting beneath the Kyushu district, together with the Philippine Sea slab. In western Kyushu, the shallow Moho is spreading in the north–northeast–south–southwest direction in the Okinawa trough region. Based on the presence of low-velocity anomaly in three-dimensional velocity structure and seismogenic stress field of shallow crustal earthquakes, the shallow Moho is interpreted as being due to lower crustal erosion associated with a small-scale mantle upwelling in the Okinawa trough region. The velocity discontinuity undulation basically has insignificant effect on hypocenter determination of the local earthquakes, but the Moho topography makes changes in focal depths of some upper mantle earthquakes. The depth variation of the Moho discontinuity has a good correlation with the Bouguer gravity anomaly map; i.e., the shallow Moho of western Kyushu and the deep Moho of eastern Kyushu closely correlate with the positive and negative Bouguer gravity anomalies, respectively.  相似文献   

岩体结构面的多参数优势分组方法研究     

宋盛渊  王清  陈剑平  李严严  史明远 《岩土力学》2015,36(7):2041-2048

岩体中的结构面对岩体的水力和力学性质有很大影响,因此,弄清岩体中结构面的发育规律是岩体稳定性评价的基础。当结构面的产状一致,其他性质不一致时,结构面的水力学特性和力学性质是不同的。而传统的结构面优势分组方法仅根据产状数据分组,无法分辨产状相同、其他性质不同的结构面。因此,提出了一种基于量子粒子群优化算法的多参数结构面的优势分组方法。该方法通过结构面的相似性度量建立目标函数,运用量子粒子群优化算法通过搜索目标函数的全局最优解来确定聚类中心,可用于结构面多个参数的优势分组。通过对计算机模拟的多参数结构面数据的分组,验证了该方法的可靠性。最后,将该方法应用于怒江松塔水电站坝址区实测的多参数结构面数据的划分,得到了符合实际的分组结果。  相似文献   

On a nonlinear hybrid method for multiscale analysis of a bearing-capacity test of a real-scale segmental tunnel ring     

Jiao-Long Zhang  Herbert A. Mang  Xian Liu  Yong Yuan  Bernhard Pichler 《国际地质力学数值与分析法杂志》2019,43(7):1343-1372

A nonlinear hybrid method is developed for multiscale analysis of a bearing-capacity test of a real-scale segmental tunnel ring subjected to point loads. The structural analysis consists of two parts. Part I refers to modeling of bending-induced tensile cracking of the segments, resulting from the external loading. The segments are subdivided into elements, according to the crack spacing. Each element is either intact or contains one central crack band, flanked by lateral undamaged domains. A multiscale model for tensile softening of concrete is used to describe the progressive deterioration of the crack bands. After iterative determination of their state of damage, the effective bending and extensional stiffnesses of the corresponding elements are quantified by means of Voigt-Reuss-Hill estimates. The effective stiffnesses are used for linear-elastic simulations of the segmental tunnel ring. Part II refers to the relative rotation angles at the joints, which are estimated from monitoring data, using the Bernoulli-Euler hypothesis. Since the validity of this hypothesis is questionable for neck-like joints, the relative rotation angles are post-processed such that they refer to rigid body displacements of the segments. The following conclusions are drawn: The presented approach yields good estimates of crack widths. Relative rotation angles at the joints mainly result in rigid body displacements of the segments, governing the convergences. Because realistic interface models are lacking, hybrid analysis based on displacement-monitoring data allows for performing ultimate-load analysis of segmental tunnel rings.  相似文献   

Mantle discontinuities beneath Izu-Bonin and the implications     

臧绍先  周元泽  蒋志勇 《中国科学D辑(英文版)》2003,46(12):1201-1211

The detailed structure of the Earths interior is a major field of geophysics study and the existence and the properties of mantle discontinuities are its important content. Since the lateral heterogeneity was discovered with the seismic tomography method,…  相似文献   

全球地幔三维结构模型及动力学研究新进展   总被引：10，自引：0，他引：10  

朱介寿 《地球科学进展》1996,11(5):421-431

介绍了地幔三维地震模型及地球动力学最新进展，特别是１９９５年７月ＩＵＧＧ第２１届大会展示的新成果。地幔三维速度分布主要由全球数字地震台网资料求得。１００ｋｍ深度速度分布主要与板块构造有关，３５０ｋｍ深度显示了大陆与海洋的差异，１９００ｋｍ深度表现环太平洋的高速异常带。  相似文献   

Transition zone structure in a tectonically inactive area: 410 and 660 km discontinuity properties under the northern North Sea     

George Helffrich  Eugenio Asencio  Jim Knapp  Tom Owens 《Geophysical Journal International》2003,155(1):193-199

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Receiver function analysis of the North American crust and upper mantle   总被引：2，自引：0，他引：2  

D. S. Ramesh  R. Kind  X. Yuan 《Geophysical Journal International》2002,150(1):91-108

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