基于DIC方法的单轴压缩湿砂样主应变轴偏转规律实验研究

发布时间：2018-03-21 17:04

本文选题：砂样　切入点：主应变轴偏转　出处：《辽宁工程技术大学》2015年硕士论文　论文类型：学位论文

【摘要】：为了深化认识岩土材料的破坏机理及过程,研究了单轴压缩湿砂样主应变轴偏转规律。利用自主开发的基于粒子群优化的数字图像相关方法,获得了砂样观测平面内主应变轴偏转角的时空分布规律。采用双三次样条插值的方法,获取了任意位置的主应变轴偏转角,分析了砂样将来出现剪切带位置处、剪切带的中心及其尖端附近和剪切带外的主应变轴偏转角随纵向应变的演变规律。研究发现,随着纵向应变的增加,在砂样观测平面内,主应变轴偏转角的范围由分散逐渐变得稳定,大部分区域最终分布在-10-10°之间。当出现较清晰的剪切带以后(硬化阶段后期),剪切带内不同位置处主应变轴偏转角基本趋于恒定或稍有下降,大致稳定在-5-5°之间,而剪切带外各测点的主应变轴偏转角均处于发展之中,且对于剪切带两侧没有其他剪切带影响的情形,剪切带内、外主应变轴正在发生偏转的方向相反；而在剪切带尖端附近的点,主应变轴偏转角随纵向应变的演变规律比较复杂。
[Abstract]:In order to deepen the understanding of the process and the failure mechanism of rock and soil materials, the uniaxial compressive principal strain axis deflection of wet sand. Using the self-developed digital image correlation method based on particle swarm optimization, the sand observation plane principal strain axis deflection angle of the temporal and spatial distribution law. By using the method of double three spline interpolation the obtained strain in an arbitrary position of the shaft angle, analyzes the future sand shear band position, principal strain axis center shear zone and near the tip and shear band angle with the evolution of the longitudinal strain. The results show that, with the increase of axial strain, the sand observation plane range principal strain axis deflection angle by the dispersion gradually becomes stable, most of the regional final distribution between -10-10 degrees. When the shear clear belt (after hardening stage), shear bands in different positions in the main Variable shaft angle tends to be constant or decreased slightly, roughly stable between -5-5 degrees, and the shear band of each measuring point of the principal strain axis deflection angle are in development, and did not affect other shear zone in the case of shear zone on both sides of the shear zone, outside the main strain axis is happening in the direction of deflection on the contrary; and near the tip point in shear, principal strain axis deflection angle with the evolution of the longitudinal strain is more complex.

【学位授予单位】：辽宁工程技术大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TU441

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