Understanding the effect of the learning-forgetting phenomenon to duration of projects construction

The construction time needed for an operation is assembled from the average unit production time plus the buffer time. The times required to produce different units in an operation are assumed to be identical. Moreover, the unit production time preceding and following an interruption is estimated to be identical in most projects. During claims or dispute resolutions, construction professionals reject the concept of an interruption of learning-curve phenomenon. This research explores the learning and forgetting phenomena that exist in repetitive construction operations, and their influence on project productivity. The model of a learning-forgetting phenomenon integrated using a line of balance technique is shown. Using this, the loss of productivity caused by the learning-forgetting phenomenon can be predicted. The model provides an alternative method in works, resources, and cash flow scheduling; therewith, a more realistic scheduling of construction operations, resources and cash flow is achieved. © 2001 Elsevier Science Ltd and IPMA. All rights reserved.