...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of Geophysical Research. Biogeosciences >A two-phase model for compaction and damage 3. Applications to shear localization and plate boundary formation
【24h】

A two-phase model for compaction and damage 3. Applications to shear localization and plate boundary formation

机译：压实和破坏的两阶段模型3.在剪切局部化和板边界形成中的应用

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

A new two-phase theory employing a nonequilibrium relation between interfacial surface energy, pressure, and viscous deformation [Bercovici et al., this issue] provides a model for damage (void generation and microcracking) and thus a continuum description of weakening, failure, and shear localization. Here we demonstrate applications of the theory to shear localization with simple shear flow calculations in which one phase (the matrix, representing, for example, silicate) is much stronger (more viscous) than the other phase (the fluid). This calculation is motivated as a simple model of plate boundary formation in a shear zone. Even without shear the two phases eventually separate due to gradients in surface tension. However, the influence of shear on phase separation is manifest in several ways. As shear velocity increases, the separation rate of the phases increases, demonstrating a basic feedback mechanism: Accumulation of the fluid phase causes focused weak zones on which shear concentrates, causing more damage and void generation and thus greater accumulation of fluid. Beyond a critical shear velocity, phase separation undergoes intense acceleration and focusing, leading to a "tear localization" in which the porosity becomes nearly singular in space and grows rapidly like a tear or crack. At an even higher value of shear velocity, phase separation is inhibited such that shear localization gives way to defocusing of weak zones suggestive of uniform microcracking and failure throughout the layer. Our two-phase damage theory thus predicts a wide variety of shear localization and failure behavior with a continuum model. Applications of the theory to various fields, such as granular dynamics, metallurgy, and tectonic plate boundary formation are numerous. [References: 57]
机译：一种新的两相理论，采用了界面表面能，压力和粘性变形之间的非平衡关系[Bercovici等，本期]提供了损伤（空隙产生和微裂纹）的模型，从而连续描述了弱化，破坏，和剪切局部化。在这里，我们通过简单的剪切流计算论证了该理论在剪切局部化中的应用，其中一个相（基质，例如代表硅酸盐）比另一相（流体）更强（更粘）。该计算的动机是作为剪切区内板边界形成的简单模型。即使没有剪切，由于表面张力的梯度，两相最终也会分开。但是，剪切对相分离的影响以多种方式体现。随着剪切速度的增加，相的分离率增加，这说明了一种基本的反馈机制：液相的积累导致剪切集中的薄弱区域集中，从而导致更多的破坏和空隙的产生，从而导致流体的积累更多。超过临界剪切速度，相分离经历剧烈的加速和聚焦，导致“撕裂定位”，其中孔隙率在空间中几乎变为奇异，并像裂缝或裂缝一样迅速生长。在甚至更高的剪切速度值下，相分离被抑制，使得剪切局部化让位于弱区的散焦，这暗示了整个层中均匀的微裂纹和破坏。因此，我们的两阶段损伤理论通过连续模型预测了各种剪切局部化和破坏行为。该理论在诸如颗粒动力学，冶金学和构造板块边界形成等各个领域的应用很多。 [参考：57]

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号