沿时间逐步求解应力的拉格朗日分析方法研究
摘要: 拉格朗日分析方法是通过测量各个拉格朗日位置处的物理量历程来分析材料内部该位置处的其他物理量的变化,进而认识材料的动态力学性能.但现有的拉格朗日分析方法在已知粒子速度情况下,求解方法仍有不足.针对这一情况,提出了沿时间逐步求解方法,该方法能够在不做任何假定的情况下求解出应力,从而从根本上解决了只测量粒子速度这一物理量时求解应力的困难.并利用该方法对一组混凝土在冲击作用下的实验数据进行了处理,计算得到了相应的应变波形、应力波形以及加、卸载全过程的应力.应变曲线,进而揭示出混凝土材料与应变率相关的弹。塑性本构关系的特征.
Study on Lagrangian analysis for solving the stress gradually along the time
Keywords:
- 拉格朗日分析 /
- 本构关系 /
- 应力-应变 /
- 混凝土
Abstract: Lagrangian analysis method is re-analyzed, in which by measuring the physical variables of each Lagrangian positions the other physical variables of these positions of the material is analyzed, and then the dynamic mechanical properties of materials can be determined. However, the existing Lagrangian analysis methods are still inadequate when the particle velocity is known. In this paper, a new Lagrangian analysis method, with only particle velocity known, is developed, which is called step by step method along the time. The method does not make any assumption, and it can solve the problem when only particle velocity wave profiles are measured. A set of experimental data of concrete under impact is processed with the method, and the corresponding strain wave, stress wave, and stress-strain relations of the whole process of loading and unloading are calculated. Thus the strain rate dependent elastic-elastic constitutive characteristics of the concrete are revealed.