This study examined the production control practices that a high-reliability supervisor used to accelerate the schedule and minimize waste during the construction of a 10- story cast-in-place concrete building. A “high-reliability” supervisor is one who has consistently exceptional performance in both productivity and safety. From a lean construction perspective, this case study is concerned with the production control practices that achieved an accelerated schedule, while minimizing waste and maintaining high levels of safety. The authors collected extensive data from the project including interviews with the supervisor and the work crew, and regular work observations over a period of eight weeks. The paper describes the project and project demands, the activities and work sequence. The findings highlight that in order to meet the aggressive milestones, the supervisor used several production control strategies that created a highly reliable work process. These strategies included: specializing in “product lines” (horizontal and vertical concrete elements), reducing product variety (the number of different concrete mix designs), standardizing the work process, emphasizing manpower reliability and predictability (e.g., minimizing absenteeism), reducing task complexity and time pressures (by simplifying and decoupling tasks), preventing errors, exploiting limited resources (in this case the crane), etc. As a result, the case findings identify specific production control practices that minimizing waste and reduce cycle time.
Production system design, production planning, time compression, safety, high-reliability supervisor.