Patent ID: 8104996

Claim:
A two-shell structural unit for forming an outer layer of a retaining system for a steep backfilled embankment, the two-shell structural unit comprising: a front element constructed as a three-dimensional lattice structure; a spacer element constructed to resist pressure from the steep backfilled embankment, the spacer element having a stepped form on a face that is an upper face when the two-shell structural unit is installed in the outer layer and having a mount on a lower end for securing the spacer element to the steep backfilled embankment; a rear wall element that is formed of portions that are planar in shape, and that has a shape defined by a polygonal curve comprising straight line segments that extend upward when the rear-wall element is installed; and a plurality of connector pieces for fastening the front element and the rear-wall element to the spacer element; wherein the front element is spaced a distance from the rear-wall element, thereby forming a cavity that is fillable with non-compacted soil.