Fiber-reinforced polymers (FRP) composites are widely used in aerospace and civil structures due to its unique material properties. However, damage can still occur and typically manifests itself from within the composite material that is invisible to the naked eye. So as to be able to monitor the performance of FRPs, numerous sensing systems have been proposed for embedment within FRP composites. One such methodology involves the embedment of carbon nanotube-based thin films within FRP laminates for strain monitoring and potentially even damage detection. Unlike other sensors, these piezoresistive thin films possess small form factors (and thus do not serve as stress concentration or damage initiation points) and can be easily integrated during composite manufacturing. In this study, a series of laboratory tests have been conducted to characterize the static and dynamic strain sensing performance of these nanocomposites for monitoring glass fiber-reinforced polymer (GFRP) components. Specifically, monotonic uniaxial, cyclic, and fatigue tests have been conducted, while both time- and frequency-domain measurements have also been obtained. The characterization results obtained from this study indicates bi-functional strain sensitivity to monotonic loading until failure, which is found to be reproducible in cyclic dynamic loadings to amplitudes in both functional ranges.© (2011) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.