Figure 14.

The variation with radius r of the areal density $\rho (r)$ of fibre clearly follows the variation in $\rho (r){\mathbb{C}}_{11}$, which, in turn, is close to the experimentally obtained axial moduli $\mathit{\Xi }(r)$ shown by solid squares. (Note: $D_{\mathrm{i}}$ and $D_{\mathrm{o}}$ are inner and outer diameter of bamboo culm, respectively.)