State and county delivered bridge replacement project analysis

The purpose of the study was to compare the cost of state delivered bridge projects and county delivered bridge projects. A total of 190 different bridge replacement projects were analyzed. The first phase of the project focused on whether or not the project delivery type (state or county) was a significant predictor of project cost or project duration. The greatest variability in the cost of bridge replacement projects (79%), was found to be explained by project duration and bridge length, with length being the most influential. Overall, it was found that the duration of state-delivered projects was longer than the duration of county-delivered projects. In the second phase, analysis was completed to determine if a predictive model could be developed for project costs and project duration. Variables included bridge closure type (on-site detour, off-site detour, and staged build), clearance type (over water, over railroad, over canal/irrigation), number of bids received, and project location. Clearance type was found to impact construction costs, but not be a significant predictor. It was also found that projects built in stages had higher construction costs than projects using onsite or offsite detours. Using the results from Phase I and analysis from Phase II, a model was developed. The model was found to account for 86% of variation in project costs, This archived document is maintained by the Oregon State Library as part of the Oregon Documents Depository Program.  It is for informational purposes and may not be suitable for legal purposes., OrDocs shipping list 2010-23, Title from PDF cover, "February 2010.", "OR-RD-10-13"--P. i, Sponsored by Oregon Dept. of Transportation, Highway Program Office, Mode of access: Internet from the Oregon Government Publications Collection., Electronic text file (xi, 31 p. : PDF file)
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This archived document is maintained by the State Library of Oregon as part of the Oregon Documents Depository Program. It is for informational purposes and may not be suitable for legal purposes.
Abstract/Description: The purpose of the study was to compare the cost of state delivered bridge projects and county delivered bridge projects. A total of 190 different bridge replacement projects were analyzed. The first phase of the project focused on whether or not the project delivery type (state or county) was a significant predictor of project cost or project duration. The greatest variability in the cost of bridge replacement projects (79%), was found to be explained by project duration and bridge length, with length being the most influential. Overall, it was found that the duration of state-delivered projects was longer than the duration of county-delivered projects. In the second phase, analysis was completed to determine if a predictive model could be developed for project costs and project duration. Variables included bridge closure type (on-site detour, off-site detour, and staged build), clearance type (over water, over railroad, over canal/irrigation), number of bids received, and project location. Clearance type was found to impact construction costs, but not be a significant predictor. It was also found that projects built in stages had higher construction costs than projects using onsite or offsite detours. Using the results from Phase I and analysis from Phase II, a model was developed. The model was found to account for 86% of variation in project costs
Subject(s): n-us-or
Bridges -- Oregon -- Costs
Project management -- Oregon
Date Issued: [2010]