The Impact of Ramp Geometry on the Cumulative Energy Consumption Arising from Its Formation and Hauling in Quarries

Haul-road geometry influences the energy requirements of ramp construction and truck haulage, yet these stages are rarely evaluated jointly. This study assessed the energy implications of 10%, 15%, and 20% ramp gradients at the Dubie dolomite quarry in southern Poland, considering a constant vertical elevation difference of 18.6 m. Process-based energy balances covered blasthole drilling, explosive charging, blasting, and fragmented-rock collection. Volvo A45G haulage performance was analyzed using a powertrain-constrained simulation validated against on-board telemetry. Increasing the gradient shortened the ramp and reduced construction energy demand from 133.93 GJ at 10% to 95.70 GJ at 15% and approximately 59.71 GJ at 20%, corresponding to reductions of 28.6% and 55.4%, respectively. Fragmented-rock collection accounted for approximately 69–74% of construction-stage energy consumption. Although increasing gradient increased vehicle resistance and energy demand per unit distance, the associated reduction in haulage distance lowered the predicted fuel requirement per loaded uphill trip from 3.71 dm3 at 10% to 3.36 dm3 at 15% and 3.18 dm3 at 20%. The 10% value was obtained from field telemetry, whereas the 15% and 20% values represent model-based projections. When ramp construction and repeated haulage were integrated on a common functional basis of 500,000 Mg of transported material, cumulative energy demand decreased from 425.39 GJ at 10% to 359.36 GJ at 15% and 309.59 GJ at 20%. Thus, the 20% gradient represented the theoretical energy minimum among the investigated variants, whereas the 15% gradient provided a more balanced engineering solution when the increasing traction requirements and operational constraints associated with steeper ramps were considered.