Truck safety barriers for mining sites

Safescape is a Western Australian company that has recently developed a device for improved safety in open-pit mines. Serious accidents can occur when large trucks veer off the roads running around the edge of the mine. The conventional technique to mitigate the risk is to pile waste rock to form a so-called bund on the edge of the road. This method is not fail safe though as vehicles can, and do, drive completely over the bund. In this paper, we describe a new device that consists of a row of filled polyethylene shell units which are linked together and sit on the road side of the rock bund. The vertical front face of the edge protector prevents out of control dump trucks from climbing over the bund and into the pit, so that they push against the barriers and heave the broken rock behind the bund. The models developed here suggest that the primary resistance to an impacting truck is provided by the large heaving force with the barrier simply facilitating this process. The theory indicates that the total resistance is independent of truck speed, meaning that simple barrier pushing experiments are sufficient to validate the analysis. The conclusions of the theory and field tests suggest that in a worst-case scenario involving the normal impact of a 500 tonne filled dump truck, the barriers and bund move a few metres before coming to rest.