耗散结构理论及其在火成岩岩石学中的意义   总被引：2，自引：0，他引：2  

张招崇  李兆鼐 《岩石矿物学杂志》1991,10(3):221-227

本文简要介绍了耗散结构理论及其研究方法,以及它在火成岩中的应用,其中包括以下几个方面:(1)基性杂岩体的层状构造;)2)花岗岩中的球状构造;(3)斜长石的环带;(4)花岗岩体的成分分带。并讨论了这四种耗散结构的形成机理。这些耗散结构都是在远离平衡的条件下,通过内部不可逆的非线性过程,由于外界的扰动和内部的涨落造成定态的失稳而形成的。其形成的根本原因是其内部反馈机制作用的结果。斜长石的环带是时间耗散结构——极限环。利用耗散结构理论简要地解释了辽宁二道沟花岗闪长岩的成因。  相似文献   

Propagation of seismic waves in a viscoelastic medium and the effect of topography     

Yuanqing Zhu  Tianyue Hu  Ziqiang Guo 《地震学报(英文版)》1992,5(3):493-501

In this paper we have simulated the propagation of seismic waves in viscoelastic medium and calculated the effect of irregular surface topography by using finite element method. Several types of elastic and viscoelastic medium models, such as block structure, vidges and/or valley with and without a soft layer underneath have been studied. The distribution of maximum amplitude of displacement and acceleration on surface has been calculated in the case of vertically incident SH and P waves from the basement. The possible application in earthquake engineering is also discussed. The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,13, 442–449, 1991.  相似文献   

Initial Colonization Stages on Rocky Coastal Substrates     

F. X. Niell  M. Varela 《Marine Ecology》1984,5(1):45-56

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Viscoelastic relaxation of the upper mantle and afterslip following the 2014 MW8.1 Iquique earthquake     

《地震研究进展（英文）》2021,1(1):100002

An improved understanding of postseismic crustal deformation following large subduction earthquakes may help to better understand the rheological properties of upper mantle and the slip behavior of subduction interface. Here we construct a three-dimensional viscoelastic finite element model to study the postseismic deformation of the 2014 M_W8.1 Iquique, Chile earthquake. Elastic units in the model include the subducting slab, continental and oceanic lithospheres. Rheological units include the mantle wedge, the oceanic asthenosphere and upper mantle. We use a 2 ​km thick weak shear zone attached to the subduction fault to simulate the time-dependent stress-driven afterslip. The viscoelastic relaxation in the rheological units is represented by the Burgers rheology. We carry out grid-searches on the shear zone viscosity, thickness and viscosity of the asthenosphere, and they are determined to be 10¹⁷ ​Pa ​s, 110 ​km and 2 ​× ​10¹⁸ ​Pa ​s, respectively. The stress-driven afterlsip within the first two years is up to ~47 ​cm and becomes negligible after two years (no more than 5 ​cm/yr). Our results suggest that a thin, low-viscosity oceanic asthenosphere together with a weak shear zone attached to the fault are required to better reproduce the observed postseismic deformation.  相似文献   

带暗支撑短肢剪力墙结构弹塑性地震反应分析     

张建伟  曹万林  邹景春  赵长军 《震灾防御技术》2007,2(2):187-192

在试验研究的基础上,本文建立了带暗支撑短肢剪力墙结构的弹塑性时程分析力学模型。运用DRAIN2D 程序,对带暗支撑短肢剪力墙结构及普通短肢剪力墙结构进行了弹塑性地震反应时程分析,对二者计算的结果进行了比较。计算分析表明,带暗支撑短肢剪力墙结构的地震反应,明显小于不带暗支撑的普通短肢剪力墙结构。  相似文献   

SM植物胶冲洗液的流变性分析与探讨   总被引：1，自引：0，他引：1  

占样烈 《地质与勘探》2010,46(2)

文章介绍了冲洗液的几种常见流变模式,并对这几种流变模式的流变曲线及其特点作了简单分析总结。通过多次室内试验测得SM植物胶冲洗液的各项流变参数,并根据这些参数作出它的流变曲线,通过与传统流变曲线作对比总结出SM植物胶冲洗液的流变方程表达模式为幂律模式;结合实践中常见的一些现象并通过两组不同的特征试验证明SM植物胶冲洗液为粘弹性流体而非传统观念上的假塑性流体;与传统泥浆对比试验证明SM植物胶冲洗液的流变性能优越;文章结尾对SM植物胶冲洗液的流变参数作了简单的分析讨论。  相似文献   

深基坑支护方案综合评价模糊优化理论模型及其应用   总被引：3，自引：0，他引：3  

冯玉国 《岩土工程技术》2001,(1):38-40

运用扩展的最小二乘方准则构造目标函数，建立了一种适用于深基坑支护方案综合评价的模糊优化理论模型。以某大厦深基坑支护拟用的4种方案评价为例，说明了该模型的应用，并与采用其它方法得到的结果进行了对比。  相似文献   

层状弹性介质中地震波运动学问题研究     

赵国敏  张中杰  滕吉文  孟补在  白云  黄玉国 《吉林大学学报(地球科学版)》1995,(3)

完全弹性介质中，进行地震波射线追踪时需要确定射线的出射角；在非弹性介质中，除了确定此射线出射角之外，还需要确定另外一个角，即波前面与常振幅平面的夹角──衰减角。基于惠更斯原理，研究了确定射线出射角与衰减角的一种有效方法，进而对层状非弹性介质中地震波运动学问题进行了一定的理论研究与数值计算。  相似文献   

The effects of rheological layering on post-seismic deformation     

E. A. Hetland  B. H. Hager 《Geophysical Journal International》2006,166(1):277-292

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Analytical expression between the impact damping ratio and the coefficient of restitution in the non‐linear viscoelastic model of structural pounding     

Robert Jankowski 《地震工程与结构动力学》2006,35(4):517-524

Earthquake‐induced structural pounding has been recently intensively studied with the help of different models of impact force. It has been verified through comparisons, that the non‐linear viscoelastic model may be considered somewhat the most accurate one among them. The aim of this short paper is to derive an approximating formula relating the impact damping ratio, as a parameter of the model mentioned, with a more widely used coefficient of restitution. The accuracy of the derived analytical formulation has been confirmed through the comparison with the results of numerical simulations. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献