Crew production rates for contract time estimation: Bent footing, column, and cap of highway bridges

Both the importance and process of estimating highway construction time have increased in significance as roadway user costs themselves have become more significant. In estimating construction time, few parameters are more significant than work item crew production rates and factors significantly affecting the rates. A standardized data collection tool was used to acquire a total of 93 data points from 22 ongoing Texas highway projects between February 2002 and May 2004, for selected critical work items: Footing, column-rectangle, column-round, and cap. With the data, several hypothesized drivers of the crew production rates were analyzed. The statistically significant drivers found from the analyses include: footing size (m 3/ea), excavation depth (m), and number (No.) of footings per bent for footing work item; column size (m 3/ea), column height (m), No. of columns per bent for column-rectangle; column height (m), diameter (m), and No. of columns per bent for column-round; cap size (m 3/ea), cap length (m), and shape of cap (rectangle versus inverted T) for cap. Findings from this study will enable highway agencies to enhance accuracy of contract time estimation for highway bridge construction. The methodology for obtaining field-based production rates will also be beneficial for future researchers.