| Spectral mechanics have emerged as a new branch in the field of experimental mechanics by using spectroscopies as measuring methods and analyzing techniques. Compared with photomechanical methods, spectral techniques provide an abundant dimension of information with the ability to achieve high spatial resolution, enhanced testing efficiency, non-contact and non-destructive measurement, which are suitable for in-situ and online experimental stress analyses. In recent years, several spectroscopic techniques were developing rapidly, including micro-Raman spectroscopy, micro-Fluorescence spectroscopy, Terahertz time-domain spectroscopy, and X-ray diffraction. Additionally, some novel spectroscopic methods were also introduced to experimental studies relative to mechanics, such as Brillouin scattering spectroscopy, optical coherence elastography, hyperspectral imaging, spectral reflectometry, and second harmonic generation. In this paper, the basic principles, features, and recent representative achievements of the former four well-studied spectral techniques were briefly summarized. Then, focusing on the latter five newly developed spectral methods, the principles, advantages, pioneering achievements and current bottlenecks of which were detailedly presented. Finally, the main trends and directions for the future developments of spectral mechanics were discussed. This review aims to present a systematic reference for researchers engaged in experimental research of mechanics and interdisciplinary studies, and offer a rapid and comprehensive understanding of the field for young researchers interested in fundamental studies on spectral mechanics. |
