Iowa Statewide Urban Design and Specifications

About the research

The Wisconsin Department of Transportation (WisDOT) has an important responsibility to provide safe and efficient transportation infrastructure for the traveling public. This is achieved by ensuring that assets operate reliably, while also limiting unnecessary restrictions to bridge traffic. As such, any decision to load post a bridge must ensure safety while also not being overly restrictive. WisDOT has recognized that there are many challenges in assessing bridge condition/performance and, as a result, has been updating their bridge load-rating program to include more data analytics, especially for their timber bridge inventory.

The goals of this project are to assist WisDOT in the following: 1) development of updated wheel load distribution width equations through physical load testing and analytical modeling of longitudinal timber slab bridges, 2) develop guidelines for conducting future load testing and establishment of the proof legal load capacity of similar bridges, 3) development of guidelines for potentially increasing the live load capacity of laminated timber bridges using various retrofit techniques, 4) validation or recommendation of improved moisture related timber correction factors based on field measure data, and 5) ultimately, the reduction in the number of timber slab bridges with over conservative load postings based on all of the above.