In order to compute gauge-averaged strain (με) at the strain gauge location, displacements at nodes located at the boundaries of the strain gauge can be used with the initial gauge length (distance between the nodes) to compute Cij which is the gauge-averaged strain resulting from applying the pulse load Uj to the slit of depth ai. ( Schajer, 1993). The resulting compliance matrix for CF/epoxy composite with no CNF content is reported below. The compliance coefficients for CNF/CF/epoxy composites are slightly different.