爆破动态应力场量化研究原理与初步实验

PRINCIPLE AND PRELIMINARY EXPERIMENT OF QUANTITATIVE ANALYSES IN BLASTING STRESS FIELD

以近年发展的激光动光弹与全息干涉法相结合,进行实验室二维爆破模型的全场动应力求解研究。在一次加载中可同时获得四个不同时刻的等和线与等差线条纹,从而在较为一般情况下完整地给出模型的全场动应力,解决了以往爆破模型全场主应力无法获得的难题。还阐述了主应力分离的理论公式;建立了相关的实验系统;用光程变化原理研究等和条纹的级次,作为实例,对双孔迭加应力场进行了定量研究。

A new method in which dynamic holophotoelasticity combined with holographic interferometry is used in laboratory test to study the full field dynamic stress for two-dimensional blasting model. Four groups of transient isopachic and isochromatic fringe patterns at different time are acquired at one load, therefore, an integrated full field dynamic stress of the model is gotten at general conditions for the first time, and the two principal stress of the blasting model is established. In the paper, the theoretical formulas of separate principal stress are derived, the experimental system is setup, the principle of optical path changing is used in judgement for fringe orders, as an example, result of quantitative analyses during stress wave interference when two-hole simutaneously detonated charges is acquired. This paper is very important for full field analyzing of the explosive charge.