▎ 摘　　要

In this paper, an amplitude-modulated vibro-acoustic (AMVA) technique using a transmitted amplitude-modulated pump wave to achieve lower power consumption and versatility is pro-posed to characterize different thermal damage levels of pristine graphene mortar specimens with various dosages. In previous studies, only the primary field u1 and secondary field u2 were considered in the theoretical model. Hence, some higher-order sidebands were not included even though they are frequently presented in experimental results and useful for damage detection purposes. Therefore, a theoretical model containing higher-order effects is established to include those higher-order sidebands. A nonlinear parameter beta is defined based on this theoretical model, and experimental results demonstrated that beta is feasible and sensitive to characterize thermal damages as well as distinguish various dosages of cement-based materials when compared to the results of the conventional resonant frequency technique. Therefore, AMVA technique has great potential to be a reliable and efficient technique for evaluating microstructural changes in cement-based materials.