Efforts on optical scale imaging for physically observing slow dynamics

Nonlinear vibration behaviors present an opportunity to probe natural composite materials with an undefined level of detail. Existing characterization techniques for composite materials are often limited in resolution due to the heterogeneous nature of composite materials. The work carried out in this paper aims to optically observe the micro-structure of cement paste before and after a series high strain vibration events. Images are captured at multiple levels of driven vibration and compared against an initial reference image. Small changes in optical microscopy are recorded, however no optically sized cohesive regions of change are identified after all levels of excitation. The work builds a consensus that more advanced imaging techniques are required to continue to investigate dynamic nonlinear manifestation of the natural composite material micro-structures.