Production control in earthworks: Concepts and metrics

The lean construction theoretical lens afforded by the Transformation-Flow-Value (TFV) theory has led to changes in the way production is understood in building construction projects. However, this new perception of production has not taken root in the earthworks and infrastructure sectors, primarily because of the difficulty in discerning what the products are and how they flow. This research addresses the fundamental question of production flow in the specific context of earthworks. It proposes a novel lean view of production flow in earthworks, and it validates the proposed model by developing and testing assessment procedures for evaluation of the quality of production flow. Its metrics apply measurements of throughput, cycle time, work in progress, and waste to enable improved situational awareness for effective decision making in managing execution of earthworks onsite. The measurements use monitoring data acquired from machine control technologies, linked to a specialized information schema developed to represent continuous elements (e.g., road courses or landfills) using discrete elements. The procedures are demonstrated on a reservoir embankment construction project. Three different theoretical production scenarios are presented to illustrate the applicability of production theory and of the metrics and procedures to the context of earthworks.