Activity Analysis for Continuous Productivity Improvement in Construction

Abstract

In the construction industry, onsite labour is one of the most variable and costly factors which affect project profits. Due to the variable nature of construction labour and its correlation with profits, construction managers require a comprehensive understanding of the activities of workers onsite. For project success, it is important that workers are spending the majority of their time installing materials which advance the project. This material installation time is known in the construction industry as “direct-work” or “tool time”. Site management should continuously seek to improve the direct-work rate through the life of the project. A review of the literature indicates that no workface assessment method exists in the literature which provides: (1) a detailed description of worker activities, and (2) a continuous productivity improvement process to help management identify productivity inhibitors affecting site labour, to develop a plan to reduce or eliminate these issues, and to measure improvements as a result of these changes. In response to this need, this research has focused on the development of a workface assessment method called activity analysis. Activity analysis is a continuous productivity improvement process which efficiently measures the time expenditure of workers onsite and identifies productivity inhibitors that management must reduce or eliminate to provide workers with more time for direct-work activities. Six case studies were conducted to verify the feasibility of the activity analysis process. Further, cyclical data from two major construction firms was collected and statistically analyzed to validate the hypothesis that activity analysis can improve direct-work rates. It has been concluded that activity analysis, as a continuous productivity improvement process, is both feasible and when continually applied to a construction site, can significantly improve direct-work rates through the life of a project.