The dynamic failure behavior of mortar under impact loading is characterized through plate impact experiments. The study concerns the possible existence of failure waves in mortar. The analysis focuses on the spall strength in different regions of impacted specimens and the evolution of longitudinal and transverse stresses under normal impact loading. The diagnostics used are VISAR interferometry for surface velocity measurement and embedded PVDF gauges for internal stress measurement. Experiments conducted do not provide evidence for the occurrence of failure waves. While the study suggests that a threshold impact velocity is required to initiate failure, a clearly defined failure wave that propagates behind the loading wave is not observed. Instead, a gradual failure process initiating at the arrival of the compressive wave is found. This gradual failure process is in contrast to the well-defined failure front in the failure wave phenomenon in glasses. ©2000 American Institute of Physics.