Production rates depend largely on the quantity of structural fill placed each day and the reinforcing strip length.

As a guide, under normal working conditions, a 4 man gang could build 30m² per day given the wall height was up to 7m and 330 tonnes of fill was placed and compacted.

Large wall areas have more scope for utilising plant and labour more efficiently, and as such daily construction rates of over 30m² are achievable.

Firstly, a small, unreinforced concrete levelling pad is cast insitu as a flat surface for placing panels on. The initial course of TerraClass or TerraQuad panels is then placed onto the levelling pad, braced and aligned. The panel placing method is such that the wall elevation has a castellated appearance, which means that as panels are lifted into position, they are clamped to adjacent panels which in turn are supported by Reinforced Earth fill. Prior to backfilling the panels, the rear face panel joints are covered with filter cloth to prevent loss of fine backfill particles, whilst still allowing water to drain through. Horizontal joints are controlled by placing EPDM pads between panels.

Acceptable fill material for Highways structures is 6I or 6J frictional fill as described in the Manual for Construction of Highways Works, or frictional fill as described in BBA certificate No. 99/R106 (click here to download a copy)

The construction technique allows the main building activities to be carried out from the backfill side of the wall, as such the structure is stable during construction, allowing equipment to operate on top of any layer.