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1.
显微构造变形热年代学是一种新兴的研究构造变形热年代学方法,能够解决一些常用方法无法解决的或很困难的构造问题。显微构造变形热年代学利用因构造变形事件而产生的新生矿物结晶年龄来测定小至一般的构造变形,大至区域构造乃至造山带或碰撞带构造变形的年龄,建立构造演化时间序列,并可以计算其变形速率或隆升速率。  相似文献   

2.
Talbingo Dam is a well instrumented, 162m high rockfill structure with an upstream sloping silty clay core, located in the southern New South Wales, Australia. A non-linear finite element analysis of its behaviour was carried out under plane strain conditions, simulating its construction, reservoir filling and steady seepage loading stages. Material parameters are determined from triaxial tests on the rockfill, core, filter and transition materials, compacted to field dry density and moisture content. All materials show non-linear stress–strain behaviour, with rockfill exhibiting work softening at large strain. Mohr envelopes for rockfill are slightly curved but linear approximations are acceptable. When compared with stresses and deformations at maximum cross section, the analytical results show good agreement in most areas. A non-linear model for pore pressure response is used successfully to predict the high pore pressures in the lower region of the core. A stability analysis performed for the end of construction stage, based on finite element stresses, shows that the design safety factors are slightly conservative.  相似文献   

3.
This paper gives a brief account of the results of a series of oedometer tests and triaxial creep tests on frozen soils.

The oedometer tests are performed on artificially frozen sand, silt and clay. The tests also include ice as a reference material. The results are given by parameters describing the tangent deformation modulus and the time resistance against creep.

The triaxial creep tests are carried out on the artificially frozen clay, and on a permafrost clay from Spitsbergen. The data are interpreted in accordance with Hult's theory. The artificially frozen clay shows much higher creep resistance than the permafrost clay.

In addition to deformation moduli and creep parameters the routine data of the materials tested are also included.  相似文献   


4.
Li Zuoqin 《岩土力学》1989,10(4):21-29
This paper presents the variations of void ratios, compression coefficients, compression index and compression modulus of Xiamen muck with consolidated pressure at beginning. The second section describes the laws of coefficient of consolidation variation with pressure or void ratio. At last, it is discussed that the pressure secondary consolidation deformation develops with time at a given constant temperature and pressure. The ratio of secondary consolidation deformation to primary’s one, and quantitative relations between secondary consolidation deformation and pressure are described.  相似文献   

5.
厦门淤泥的变形性质   总被引:4,自引:1,他引:3  
李作勤 《岩土力学》1989,10(4):21-29
本文首先研究厦门淤泥的孔隙比、压缩系数、压缩指数和压缩模量随固结压力的变化特性。其次,研究了固结系数随固结压力、孔隙比的变化规律。最后,讨论淤泥在恒温恒压条件下次固结变形随时间的变化发展过程,定量地描述次固结量和主固结量的比值与次固结时间和固结压力水平的关系。  相似文献   

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Uncertainty in future reservoir performance is usually evaluated from the simulated performance of a small number of reservoir realizations. Unfortunately, most of the practical methods for generating realizations conditional to production data are only approximately correct. It is not known whether or not the recently developed method of Gradual Deformation is an approximate method or if it actually generates realizations that are distributed correctly. In this paper, we evaluate the ability of the Gradual Deformation method to correctly assess the uncertainty in reservoir predictions by comparing the distribution of conditional realizations for a small test problem with the standard distribution from a Markov Chain Monte Carlo (MCMC) method, which is known to be correct, and with distributions from several approximate methods. Although the Gradual Deformation algorithm samples inefficiently for this test problem and is clearly not an exact method, it gives similar uncertainty estimates to those obtained by MCMC method based on a relatively small number of realizations.  相似文献   

9.
The fundamental mechanical properties, time and crisscross effects of a kind of siltstone under different stress states and along different stress paths are studied with laboratory testing. A failure criterion, constitutive equations with one dimensional rate dependence and three dimensional volume deformation are proposed in this paper.  相似文献   

10.
地面沉降模型是地面沉降研究的重要内容,由于弱透水层的变形量占地层全部变形量的比重较大,因此对弱透水层固结模型的研究是地面沉降模型研究中的重要部分。笔者通过对深部弱透水层中粘性土孔隙水类型进行分析,得出深度弱透水层中孔隙水类型并对该类型孔隙水变形特性进行了研究,总结出深部弱透水层固结机理。在机理分析的基础上,提出采用非达西流计算模式对深部弱透水层计算模型进行了修正,并提出了深部弱透水层固结计算模型建议:孔隙水类型主要为扩散层内结合水时,可以采用利用非达西流修正的太沙基固结方程对深部弱透水层变形进行计算,可以参考给出的采用非达西定律修正过的一维固结方程 孔隙水类型主要为吸附结合水时,可以利用弹性本构关系模型对深部弱透水层进行变形计算。  相似文献   

11.
在桥梁运营期间,由于各种原因,会造成其不同程度的损伤和破坏。为了保证既有桥梁的安全运营和尽可能延长它的正常使用年限,应对其进行实时健康监测与安全性评估[1]。介绍了现代大跨度斜拉桥变形产生的原因、监测的内容、变形监测的实施方法,指出利用现代测量仪器和技术不仅完全可以满足大跨度桥梁管理部门提出的要求,而且还可以提高测量速度,其测量成果也具有很高的精度。  相似文献   

12.
某高路堤的变形监测   总被引:2,自引:0,他引:2  
变形监测是地质灾害防治工作的一个重要组成部分.在某高路堤的病害防治过程中,监测资料显示,该路堤的平面位移和路堤沉降均与路堤填方高度成正比;工程活动对测点的位移增量有较大影响;工程措施的实施,降低了路堤的变形增量.通过监测,证明有效的控制了施工活动带来的超量位移,为安全施工和设计变更提供了重要依据.  相似文献   

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真空预压土体的变形研究   总被引:1,自引:0,他引:1  
徐锴  梅国雄  宰金珉  殷宗泽 《岩土力学》2007,28(11):2471-2474
对真空预压的研究现状进行了总结,分析了该法的加固机理,并指出了在实际使用过程中所遇到的问题。研究表明,真空预压的加卸载实际上是以小主应力方向加卸载为主的过程;在卸去真空的过程中,小主应力方向的卸载会削弱土体的竖向回弹,土体不会出现明显的回弹现象,甚至可能继续沉降;模拟真空预压应力路径的试验需要更加合理的设计。  相似文献   

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本文通过实验,研究了一种介于岩石与土之间的软岩--粉砂岩在不同应力状态和应力路径下的基本力学性质、时间效应和交叉效应,提出了一维率相关型本构方程、三维体积应变本构方程以及破裂准则。  相似文献   

17.
上海市地铁一号线隧道变形测量及规律分析   总被引:17,自引:0,他引:17  
本文以上海市地铁一号线黄陂南路站近一年多种隧道变形测量采集整理分析为例,详细总结和讨论了地铁隧道变形测量的方法,对地铁一号线黄陂南路站附近上下行隧道变成进行了规律分析,同时对地铁一号线隧道运营以来整条隧道沉降变形规律进行了剖析。  相似文献   

18.
糜棱岩化过程中矿物变形温度计   总被引:17,自引:0,他引:17  
对有效确定中—低温下糜棱岩变形温度一直以来都没有比较理想的方法,而在研究韧性剪切带过程中对其变形温度的确定又常是必不可少的。根据近年来国际上对天然石英、长石、方解石等矿物变形的研究成果,总结了利用矿物变形指示变形温度的方法。在不同的温度条件下,长石与石英的变形方式具有阶段性,其变形与动态重结晶型式与温度具有明显的对应关系。石英变形中的滑移系及其C 轴组构图主要受变形温度的控制。低温变形中的方解石e 双晶纹形态也与温度呈密切的相关性。观测这些矿物变形的显微构造,可以很好地估计韧性剪切带糜棱岩化过程中的变形温度。  相似文献   

19.
Taking the Jinchang gold-copper field in Yinan County, Shandong Province, China, as an example, the authors have proposed that the migration and concentration of ore-forming substances carried in the hydrothermal solutions might be mainly controlled by the structural deformation taking place during the mineralization epoch. It has been found that the ore-forming elements are generally concentrated in the places with strong structural deformation and that different types of ore bodies occur in different parts of deformational structures, In addition, the authors have conducted a quantitative evaluation of the structural control over the emplacement of ores through petromechanical experiments, measurement of physico-mechanical parameters of the rocks, inversion of the stress field and simulation of distribution of migration potential of the ore-forming solutions with the theory of infiltration mechanics.  相似文献   

20.
Simla Hills form a part of Lesser Himalaya. Metamorphic rocks of this area (Pre-Cambrian), forming Chail-Jutogh nappe, are thrust over a series of mostly unfossiliferous rock formations ranging in age from Palaeozoic to Eocene. The rocks of the area are characterised by meso-structures belonging to three phases of deformation. The second phase structures, both in the allochthon as well as in the para-autochthon units are synchronous with the nappe formation. The third structure in the para-autochthon unit has been related with the movement of nappe. A model explaining the probable kinematics of thrusting in the Simla Hills has been suggested.
Zusammenfassung Die Simla-Berge sind ein Teil des Lesser Himalaya. Metamorphe Gesteine dieses Gebietes (Präkambrium), die die Chail-Jutogh-Decke bilden, sind über einer Serie vorwiegend fossilfreier Formationen (Paläozoikum bis Eozän) überschoben. Die Gesteine dieses Gebietes sind durch Meso-Strukturen, die zu drei Phasen der Deformation gehören, gekennzeichnet. Die Strukturen der zweiten Phase, zu der allochthone sowie para-autochthone Einheiten gehören, sind gleichaltrig mit der Anlage der Deckenbildung. Die Strukturen der dritten Phase in der para-autochthonen Einheit hängen mit der weiteren Bewegung der Decke zusammen. Ein Modell, das die wahrscheinliche Kinematik der Überschiebung in den Simla-Bergen erklärt, wird vorgeschlagen.

Résumé Les monts Simla représentent une partie du « Lesser Himalaya ». Les roches métamorphiques de cette région (Précambrien), formant la nappe du « Chail-Jutogh », ont glissé par-dessus une série de formations (du Paléozoique à l'Eocène) en majorité dépourvues de fossiles. Les roches de cette région sont caractérisées par des interstructures appartenant à trois phases de la déformation. Les structures de la 2e phase, auxquelles appartiennent les unités allochtones et para-autochtones se sont formées en même temps que la nappe. Les structures de la 3e phase, dans l'unité para-autochtone, sont en rapport étroit avec le déplacement postérieur de la nappe. Une possibilité d'explication de la cinématique probable du glissement dans les monts Simla est proposée.

Simla Lesser Himalaya. — —, Chail-Jutogh, , - . -, . - , - , . - . , , , .
  相似文献   

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