An investigation into opportunities for improvement of surface mine haul road functional design, construction and maintenance

Mine haul roads are a key component of a mining operation. However, design of haul road pavements often follows an approach that is heavily reliant on site experience. This approach does not allow an assessment of the production impact of different design options. This paper compares the estimated haul truck energy consumption for a range of pavement wearing course materials including mine waste (overburden), select gravels, mechanically stabilised mine waste and cementitiously modified mine waste. Haul truck energy consumption was estimated from rolling resistance, which was determined from the pavement roughness. Modelling of pavement roughness included material, traffic and maintenance inputs. Samples of each material type were collected from an iron ore mine in the Pilbara region of Western Australia. The analysis shows that the energy consumption correlates best with the fines content and activity, represented by the Shrinkage Product, of unbound wearing course materials. As a result lower truck energy consumption appears possible with the use of select gravels, mechanical stabilisation and cementitious modification.