RECO was originally awarded the design and supply of two 17.3m high Reinforced Earth dump structures. But shortly after the award, significant falls in the price of coal caused BMA to review the project, and one of the structures was shelved. RECO was ultimately contracted to supply one structure only.
Dump structures provide a robust platform from which a loaded truck can dump excavated materials into a hopper for crushing before it is conveyed to the next stage of treatment.
In this case, the dump wall geometry formed a slot arrangement that would allow the option of using rear dumps to dump from the top of the walls or, alternatively, to place a bridge across the top of the slot to allow for a belly dump arrangement.
In the case of a bridge set up, the opposing Reinforced Earth walls across the slot needed to be designed to carry the dead load from the bridge beams, the entire live load of the trucks, and associated horizontal loads as the trucks moved across the bridge.
Though this represents a significant load, Reinforced Earth walls are robust and quite capable of carrying this and heavier loads. The mining department of our business is often required to supply some of the tallest and most heavily loaded structures throughout the world.
As Caval Ridge is a coal mine, the Reinforced Earth walls use concrete facing panels. Concrete panels ensure long term durability in the corrosive coal environment.
Likewise to ensure the galvanised steel straps would also remain durable for the life time of the structure (30 years), an HDPE membrane is placed to the top of the structures to prevent ingress of contaminated water to the Reinforced Earth block.
