ACTION-RESPONSE MODEL AND LOSS OF PRODUCTIVITY IN CONSTRUCTION

Unanticipated conditions on a construction project sometimes result in a significant loss of productivity. The conditions that may affect productivity-adverse weather, scheduled overtime, and material shortages, to name a few examples-have received considerable attention in the literature. However, both experience and a detailed examination of this literature reveal that these conditions do not necessarily lead to a loss of productivity. Furthermore, when such losses are observed, their extent varies from project to project, from activity to activity, and from crew to crew. Other factors and processes must therefore be involved. The action-response model of productivity loss in construction identifies these factors and processes. The model graphically depicts how a variety of factors may interact to cause a loss of productivity: how a crew is influenced by these factors and how the management of crews can mitigate, eliminate, initiate, or exacerbate any particular loss of productivity. By applying the model to three case studies, a new approach to evaluating loss of productivity is illustrated.