Figure 7.

Kinematics of the arterial wall showing an intact artery in the reference (stress-free configuration) Ω_R where the circumferential stress is released by the radial cut resulting in opening of the arterial ring into a sector with angle α. The artery is then transferred to the unloaded configuration via F_R–U, i.e. by closing the sector. In the unloaded configuration Ω_U, the artery contains residual stresses but has no internal pressure or axial force. Finally, the unloaded arterial segment is loaded with an internal pressure p_i and an axial force F_z resulting in the transformation F_U–C to the current (loaded) configuration Ω_C. Note that the dimensions of the arterial segment in all three configurations are different.