Estimating Productivity Rates for Establishing Contract Time: Fid-Bau Portal

Estimating Productivity Rates for Establishing Contract Time

Flaten, Brent T. / Nassereddine, Hala / Whited, Gary C. / Hanna, Awad S.

Construction productivity plays a pivotal role in construction and is a major determinant of the success of any project. Productivity rates are used by highway design engineers to estimate the project contract completion time when preparing final contract documents for bidding purposes and contract administration. Establishing realistic and accurate contract completion times is particularly critical in cases where the contract contains incentive and disincentive clauses or involves cost plus time bidding. However, the numerous factors that could affect productivity make the prediction of productivity rates on future projects more challenging. For example, when a state highway construction project is bid, design engineers must set and specify a reasonable time for completion of the project. Engineers rely heavily on accurate productivity data of individual construction activities for determining contract time. Poor productivity data affects the accuracy of forecasted activity durations, and inaccurate activity durations make it impossible to produce a reliable construction schedule. This paper presents a method for estimating future productivity that accounts for the variability in productivity of construction activities. Due to project condition first, several project factors that can affect highway construction productivity were identified. An online data collection tool was then developed in which construction project personnel rated their respective projects on several project specific factors and provided observed production rates of several construction activities including: earthwork, concrete paving, asphalt paving, bridges, structures, and miscellaneous. Next, sequential regression analysis was used to incorporate project specific factors into models to predict future productivity rates on future projects. Finally, a productivity estimation tool was created to predict productivity on future projects based upon project condition factors. Models generated by this study have predicted future productivity on highway construction activities with varying degrees of accuracy, and this accuracy will improve as more data is collected and incorporated into the models.