Improving the operational efficiency of road construction machinery through automated technical condition monitoring

Abstract

The fleet of road construction machinery in the Russian Federation is shrinking while the volume of road works is maintained: at the end of 2025 construction organisations operated 16.7 thousand self-propelled single-bucket excavators, 8,2 thousand bulldozers and 4,5 thousand self-propelled graders, with the share of machines beyond their service life reaching 23,1-33,3%. The current maintenance system relies on fixed intervals of operating hours established by Annex 3 of MDS 12-8.2007, whereas automated monitoring produces a continuous stream of data on the condition of assemblies; the quantitative relation between these two grounds for scheduling repair actions remains undefined. The purpose of the study is to separate the contribution of automated condition monitoring to the growth of the technical availability factor from its contribution to the restructuring of fleet downtime. An original model of the annual time balance of a machine divided into four subsystems has been developed, calculations have been performed for three modes of scheduling repair actions, and factor decomposition by chain substitution together with sensitivity analysis has been applied; threshold values follow GOST R ISO 20816-3-2023 and GOST 17216-2001. The calculation shows that the transition from the preventive maintenance system to extended automated monitoring raises the technical availability factor of a crawler excavator from 0,872 to 0,896, reduces the share of emergency downtime from 59.5 to 29.0%, and shortens total downtime by only 18,5%. The machine-hour cost falls by 147,3 roubles, or 3,44%, with 76,2% of this reduction produced by the increase in operating hours and 23,8% by lower annual expenses. The elasticity of the technical availability factor with respect to the share of prevented failures equals 0.026, while the elasticity of the share of emergency downtime equals minus 1,344. The two-order difference means that automated monitoring changes mainly the nature of the repair action, moving it from the emergency mode to the planned one, and that the integrated availability indicator is poorly suited for assessing the change that actually occurs; the commensurate indicator is the downtime structure.