DEVELOPMENT OF TENSOR FIELD CT-METHOD FOR HYBRID TECHNIQUE IN STRESS AND STRAIN ANALYSES

本研究的主要目的是克服偏振测量技术中偏振轴沿入射光路沿着旋转的困难，建立一种既可用于对称应力场又可用于非对称应力场的二维和三维光弹性应力应变分析的方法。（1）Jone矩阵傅立叶图像旋光技术：利用1998年的补助金，到上个财政年度末，旋光技术的硬件系统已经建立。然后，二维场的技术被成功地应用于精确测量和确定延迟，方位角和椭圆度角在薄和厚盘径向压缩下。为了确定三维球体模型中的次主应力场，发展了双光束入射技术。虽然还需要进一步改进， ...更多信息 完成了基本的算法和技术。(2)使用三色激光的散射光光弹性技术：另一种具有很高期望的3D分析方法是使用三色激光作为光源的散射光技术的改进，摆脱了目前使用单色光的技术。本文成功地分析了对径压缩球体在对称和非对称应力分布平面内的次主应力差和方位角。方位测量精度的进一步提高仍然存在，但该技术被证明是非常有用的。(3)利用椭圆偏振白色光的光弹性和光粘弹性技术：在当前的光（粘）弹性技术中，必须获得两种以上不同的光学信息。这一事实意味着不可能追踪应力场的时间变化，特别是在裂纹尖端和/或接触区域处于运动状态的情况下。所提出的技术能够同时测量两个isochromatics和isoclinics与一个单一的曝光，使用椭圆偏振的白色光。该技术的几个应用程序的裂纹尖端应力场的评估成功地证明。少

The main purposes of this study are how to overcome difficulties in accurate and precise measurement of three parameters in the polarimetry technique eliminating the rotation of polarization axis along the path of incident light, and to establish a useful method for 2D and 3D photoelastic stress and strain analysis not only in symmetrical but in unsymmetrical stress fields. The results are summarized as follows ;(1) Jone's Matrix Fourier Image Polarimetry Technique : Till the end of last fiscal year, the hardware system for the polarimetry technique has been established utilizing the grant-in-aid in 1998. Then, the technique for 2D fields is successfully applied to the accurate measurement and determination of retardation, azimuth and ellipticity angles both in thin and thick disks under diametrical compression. In order to determine the secondary principal stress field in a 3D sphere model, double beam incident technique is now developed. Although some further improvements are needed, … More the fundamental algorithms and techniques are completed.(2) Scattered Light Photoelasticity Technique with Tricolor Laser : Another approach to 3D analysis with high expectation is the improvement of the scattered light technique using a tricolor laser for light source sloughing off the current technique with a monochromatic light. In this study, secondary principal stress difference and azimuth angle in a sphere under diametrical compression is successfully analyzed not only in symmetrical but unsymmetrical planes of stress distribution. Further improvement in accuracy of azimuth measurement is still exist, but the technique is proven to be very useful.(3) Photoelastic and Photoviscoelastic Techniques with Elliptically Polarized White Light : In the current photo (visco) elastic technique, more than two different optical information have to be obtained. The fact means that it has been impossible to trace the time variation of stress field, particularly in cases of crack tip and/or contact regions under moving condition. The technique proposed enables simultaneous measurement both of isochromatics and isoclinics with a single exposure, using elliptically polarized white light. Several applications of the technique to the evaluation of crack tip stress field is successfully demonstrated. Less