有限元方法在地震孕育过程与前兆机理研究中的应用进展     

陈玉香  杜建国  刘红 《地震》2007,27(4):99-109

有限元方法的基本思想是将连续的求解区域离散为一组有限个、 且按一定方式相互联结在一起的单元的组合体。 有限元方法是目前应用最为广泛的数值模拟方法, 由于能够将复杂介质的力学本构关系及边界条件问题转化成为常规问题的计算程序, 所以越来越多的地震学者将其应用于地震成因与前兆机理研究中。 该文着重介绍了有限元数值分析方法及其模拟在地震孕育过程与前兆机理研究中的应用进展, 并提出开展小尺度规模如岩石中矿物颗粒之间的力学行为的有限元模拟研究等几点建议。  相似文献   

松散砂岩边坡支护方法及施工应注意的问题     

韦君毅  苏荣琨  侬战 《南方国土资源》2007,(8):68-70

文章以南宁盆地内较为典型的某高边坡场地为例,简述了第三系以松散砂岩为主的高边坡在支护中应选择的施工方法,分析讨论在施工中易出现的问题,并提出相应的解决办法.  相似文献   

垦区普阳农场实施“退居还耕”工程     

郝云中  战英杰 《黑龙江国土资源》2007,(6):30-30

垦区普阳农场以新农村建设为契机，对居民点实施“撤队并点”。工程竣工后，农场将有10个居民点“消失”，可新增耕地4500亩。  相似文献   

内蒙古二连盆地乌兰察布坳陷白垩系特征及铀成矿类型     

旷文战  蔡彤  严兆彬 《华东地质学院学报》2014,(2)

根据近年在二连盆地乌兰察布坳陷构造类型、沉积体系等方面取得的研究成果,结合前人在本区不同层位发现了不同成因类型的铀矿化,期待企望建立盆地不同构造演化阶段沉积特征与铀成矿类型之间的有机联系。研究认为本区具备多个有利的铀成矿层位和多种铀成矿类型,其中,上白垩统二连组发育冲积(扇)平原和湖泊沉积体系,有利于形成沉积成岩型铀矿床;下白垩统巴彦花群赛汉组发育河流和沼泽沉积体系,有利于形成古河谷型铀矿床;下白垩统巴彦花群腾格尔组发育扇三角洲、辫状河三角洲和湖泊沉积体系,有利于形成同沉积叠加潜水—层间氧化改造型铀矿床。  相似文献   

云南石林盆地地热地质特征及成因分析     

刘红战  张小凌  姚明波 《华东地质学院学报》2014,(1)

结合石林盆地地热异常及地热钻孔资料,对石林盆地地热田的热储构造条件、地热地质特征及地下水化学特征进行研究,该地热田热储层为元古界震旦系白云岩、白云质灰岩,热水径流特征和地温场特征受九乡石垭口断裂、牛头山古陆控制。钻孔资料显示,地温梯度为(1.5~4.8)℃/100 m,地热类型为深循环层状地热田,地下热水水化学类型为HCO3-Ca。从水文地质条件看,地下热水补给有限,应控制地热水的开发利用。  相似文献   

哈罗铁路沿线沉积物粒度特征   总被引：1，自引：1，他引：0  

赵明珠  俎瑞平  王军战  谭立海 《中国沙漠》2021,41(1):19-27

哈罗铁路开通对沿线资源的开发具有重要意义,然而自开通以来饱受风沙危害。对铁路沿线及防沙体系内沉积物粒度特征参数进行了对比分析,以期为该线风沙危害的科学防治提供有益参考。结果表明：（1）铁路沿线沉积物组成以中细沙为主,灌丛沙地分选性中等至很差,偏度以近对称为主,峰度中等至很窄;戈壁区沉积物整体分选性较差,偏度以极正偏为主,峰度以很窄为主;（2）灌丛沙地粒径频率曲线呈单峰态分布,而戈壁粒径频率曲线呈双峰或三峰态分布;哈密盆地区戈壁沉积物粒径垂直分布特征表现为上粗下细;（3）铁路沿线形成沙害的主要原因是就地起沙,防护体系内的积沙已成为危害铁路的二次沙源。  相似文献   

Sediment Transport in Rivers and Coastal Waters     

YANG  Shu-qing 《中国海洋工程》2003,17(4):527-540

Following Bagnold's approach, a relationship between sediment transport and energy dissipation is developed. The major assumption made in the study is that the near bed velocity plays a dominant role in the process of sediment transport. A general relationship between energy dissipation and sediment transport is first proposed. Then the equations for total sediment transport are derived by introducing the appropriate expression of energy dissipation rate under different conditions, such as open channel flows, combination of wave and current, as well as longshore sediment transport. Within the flows investigated, the derived relationships are fairly consistent with the available data over a wide range of conditions.  相似文献   

围隔实验中水柱颗粒物色素的动态研究     

刘红 《海洋湖沼通报》2006,(2):75-81

用高效液相色谱法(HPLC)研究了围隔实验过程中水柱颗粒物主要色素的组成及动态变化,并就滤食性鱼类鲢对水体主要色素代谢的影响进行了讨论。结果表明:水柱中的主要色素有叶绿素a、异黄素、岩藻黄素、黄体素、玉米黄素和蓝藻叶黄素等,未放鱼的围隔中实验后期各种色素含量均降低到最低水平,有鱼的围隔中鱼类密度越高则色素含量降低越多。未放鱼的围隔中叶绿素a代谢产物———脱植基叶绿素a、脱镁叶绿素a、脱镁叶绿酸a与叶绿素a的比值均大于其它围隔,有鱼的围隔中鱼类密度大的这几个比值也比较大。  相似文献   

An Approach to Stability Analysis of Embedded Large-Diameter Cylinder Quay   总被引：3，自引：3，他引：3  

WANG  Yuanzhan 《中国海洋工程》2002,16(3):383-393

The large-diameter cylinder structure, which is made of large successive bottomless cylinders placed on foundation bed or partly driven into soil, is a recently developed retaining structure in China. It can be used in port, coastal and off-shore works. The method for stability analysis of the large-diameter cylinder structure, especially for stability analysis of the embedded large-diameter cylinder structure, is an important issue. In this paper, an idea is presented that is, em-bedded large-diameter cylinder quays can be divided into two types, i.e. the gravity wall type and the cylinder pile wall type. A method for stability analysis of the large-diameter cylinder quay of the cylinder pile wall type is developed and a method for stability analysis of the large-diameter cylinder quay of the gravity wall type is also proposed. The effect of sig-nificant parameters on the stability of the large-diameter cylinder quay of the cylinder pile wall type is investigated through numerical calculation.  相似文献   

Dynmnic Response Analysis for Embedded Large-Cylinder Breakwaters Under Wave Excitation     

王元战祝振宇  周枝荣 《中国海洋工程》2004,18(4):585-594

A numerical model is developed for dynamic analysis of large-cylinder breakwaters embedded in soft soil. In the model, the large cylinder is taken as a rigid body divided into elements and the soft soil is replaced by discrete 3D nonlinear spring-dashpot systems. The numerical model is used to simulate the dynamic response of a large-cylinder breakwater to breaking wave excitation. The effects of the dynamic stress-strain relationship models of the soil, the radius and embedded depth of the cylinder, the nonlinear behaviors of the soil, and the limit strength condition of the soil on the dynamic responses of the large-cylinder structure are investigated with an example given. It is indicated that the above-mentioned factors have significant effects on the dynamic responses of an embedded large cylinder breakwater under breaking wave excitation.  相似文献