Hole-drilling method using grating rosette and Moire interferometry

• Published in: Acta mechanica Sinica Vol. 25; no. 3; pp. 389 - 394
• Main Authors: Chen, Jubing, Peng, Yongsheng, Zhao, Shexu
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 01.06.2009
• Subjects: Classical and Continuum Physics; Computational Intelligence; Engineering; Engineering Fluid Dynamics; Research Paper; Theoretical and Applied Mechanics; 云纹干涉; 剪切应变场; 残余应力; 纤维增强复合材料; 钻孔方法; 钻孔测量; Moiré interferometry; Residual strain; Grating rosette; Hole-drilling
• ISSN: 0567-7718; 1614-3116
• DOI: 10.1007/s10409-008-0224-4

The hole-drilling method is one of the most wellknown methods for measuring residual stresses. To identify unknown plane stresses in a specimen, a circular hole is first drilled in the infinite plate under plane stress, then the strains resulting from the hole drilling is measured. The strains may be acquired from interpreting the Moire signature around the hole. In crossed grating Moire interferometry, the horizontal and vertical displacement fields （u and v） can be obtained to determinate two strain fields and one shearing strain field. In this paper, by means of Moire interferometry and three directions grating （grating rosette） developed by the authors, three displacement fields （u, v and s） are obtained to acquire three strain fields. As a practical application, the hole-drilling method is adopted to measure the relief strains for aluminum and fiber reinforced composite. It is a step by step method; in each step a single laminate or equivalent depth is drilled to find some relationships between the drilling depth and the residual strains relieved in the fiber reinforced composite materials.