• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文会议>International Conference on Mechanical Engineering and Mechanics vol.1; 20051026-28; Nanjing(CN) >Three-field Hybrid Element Method for the Strain Gradient Plasticity and Numerical Study on the Size Effect Near the Crack Tip
【24h】

Three-field Hybrid Element Method for the Strain Gradient Plasticity and Numerical Study on the Size Effect Near the Crack Tip

机译：应变梯度塑性的三场混合元法及裂纹尖端附近尺寸效应的数值研究

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

For the Fleck-Hutchinson strain gradient plasticity, C~1 continuous element is required for the conventional displacement type formulation because this kind of theory fits within the framework of reduced couple stress theory where the first-order strain gradients are involved. In order to avoid the difficulties of C~1 continuity, a three-field hybrid element formulation based on the general couple stress theory is proposed for the strain gradient theory. An energy consistency condition which ensures the convergence of the element is derived from variation on the incompatible energy functional. A 4-node plane three-field hybrid element is developed on the basis of this condition. Numerical results agree well with the analytical solutions. Study on the bending of the ultra-thin beam shows that beam's bending hardening effect increases significantly when its thickness decreases. Study on stress field near the crack tip shows that the shear stress t_(θr) is 2.5 times of that of the classical fracture mechanics predicts, while normal stresses do not increase significantly. Comparing with Cauchy stresses, the couple stress is not dominant at crack tip. The size effect is only important in a zone of 10l (l is material characteristic length) around the crack tip.
机译：对于Fleck-Hutchinson应变梯度可塑性，常规位移类型公式需要C〜1个连续单元，因为这种理论适合于涉及一阶应变梯度的归结偶应力理论的框架。为了避免C〜1连续性的困难，提出了一种基于通用偶应力理论的三场混合单元公式作为应变梯度理论。确保能量收敛的能量一致性条件是由不兼容的能量函数的变化得出的。在此条件的基础上开发了一个四节点平面三场混合元件。数值结果与解析解吻合良好。对超薄梁弯曲的研究表明，当梁厚度减小时，其弯曲硬化效果显着提高。对裂纹尖端附近应力场的研究表明，剪切应力t_（θr）是经典断裂力学预测的剪切应力的2.5倍，而法向应力并未显着增加。与柯西应力相比，裂纹尖端处的耦合应力不是主要的。尺寸效应仅在裂纹尖端周围的10l（l是材料特征长度）区域中很重要。

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