Reducing Labor Productivity Losses through a Productivity Stratification Indicator

Abstract

Many factors that decrease productivity occur and recur during the execution phase of construction projects. Preventing and mitigating the impact of these factors, such as lack of materials, waiting times, exceed craftworks traveling, and mobilization, require access to productivity data at a level that allows the identification of the root causes of productivity losses. Therefore, it is critical to use proper indicators that support the implementation of effective productivity improvement practices. This study analyzes the benefits of using the productivity stratification indicator (PSI) in productivity management programs. This metric improves onsite productivity management by providing detailed, accurate, and fast indicators that enable the identification and mitigation of productivity barriers before they affect the project performance. The validation of the proposed indicator encompassed the analysis of productivity data obtained from the execution of pile-drilling activities at eight construction job sites over a one-year period. The data collection and analysis activities were divided into two well-defined periods. This allowed a comparison of the stratified productivity unit rates in the first period with those in the second period, highlighting the percentage of reduction (40%) for unit rates between both periods. The PSI graphs convey productivity indexes that explain productivity and isolate the project's unproductive areas. Access to this information enable project teams and crews to diagnose their inefficiencies at the moment they occur and to take actions immediately.