Specifies the relative position of the wall to the path. Fifteen positions are available. The location of positions 10 (center-of-gravity) and 15 (shear center) depend on the wall's section shape. The local z- axis of the wall and the center-of-gravity point of the section define positions 11 and 14. The local y-axis of the wall and the center-of-gravity point of the section define positions 12 and 13.