Fig. 6.
Storage (elastic) and loss (viscous) components of the complex shear modulus μ* = μʹ + iμʺ measured using the DST for (a) a representative control gel tested in one orientation (μA) and then rotated about the vertical axis by 90 deg (μB), and (b) a representative aligned gel tested with shear loading applied in a plane parallel to the dominant fiber axis (μ1), or in a plane normal to the dominant fiber axis (μ2). Data are shown over the frequency range of 20–40 Hz. Samples were tested at 0%, and 5% precompression; data is shown only for 5% precompression. Comparison of the components of the complex shear modulus of the (c) control gels (n = 5), and (d) aligned gels (n = 13) samples, estimated by the DST over the range of 20–40 Hz. Differences between the storage moduli (μ′ 1 and μ′ 2) and between the loss moduli (μ″ 1 and μ″ 2) for the aligned gels were statistically significant (p values as shown; Student's t-test), indicating material anisotropy. Error bars show one standard deviation.