方差莫尔圆及在位移检验中的应用

VARIANCE MOHR'S CIRCLE AND ITS APPLICATION IN THE DISPLACEMENT EXAMINATION

误差椭圆法是变形观测中进行位移检验的主要方法之一.由于误差椭圆是误差曲线的近似表示,因而用于位移检验时的误判概率与理论值不吻合.本文提出用莫尔圆进行位移检验,并通过模拟计算说明了该方法与理论设计值的一致性,文中对误差椭圆法随长、短轴比值变化而引起的弃真概率也作了讨论.

Error ellipse method is one of the chief methods for the proceeding of the displacement examination in the deformation observation. Owing to that the error ellipse is an approximation manifestation of the error curve, the faulty discrimination probability applied in the displacement examination does not agree with the theoretical value. This paper presents the displacement examination using Mohr's circle, and by simulation computation it explains the coincidence of that method with the theoretical design value. In the paper, the distortion probability of the error ellipse method caused by the variation of the ratio of the major and minor axes is also discussed.