Contact

Cody Howard
School of Engineering
785-864-2936

Study will help counties cope with deficient bridges

Fri, 04/18/2014

LAWRENCE — Deteriorated or outdated bridges along the less-traveled back roads of Kansas are a budget dilemma for county leaders throughout the state.

A new report from researchers at the University of Kansas School of Engineering provides county leaders with a tool as they decide the future of bridges on rural roads with extremely low vehicle traffic counts. The Kansas Department of Transportation provided $20,000 to fund the study.

Seventy-eight of the state’s 105 counties have bridges on low-volume rural roads in dire need of repair, replacement or removal. With an estimated cost of $150,000 per bridge – and nearly 1,000 bridges across the state in the structurally deficient or functionally obsolete categories – replacement bridges are an expensive proposition. The study provides a cost-benefit analysis on replacing a bridge compared to the cost of traveling extra miles to detour if a bridge is closed and removed.

“This study only investigated bridges located on two-wheel path roads. That could be gravel, dirt, or sand. We estimate these roads would have extremely low daily vehicle counts, 25 a day or less,” said Tom Mulinazzi, professor of civil, environmental and architectural engineering, and one of the authors of the study.

Researchers did not gather individual vehicle counts from each bridge in question. They simply used the presence of a two-wheel path road as a method to estimate vehicle counts.

The study analyzes potential detour routes for all 992 structurally deficient or functionally obsolete bridges on rural Kansas roads with fewer than 25 vehicles a day, the vast majority of which are in the northern and eastern parts of the state. Nearly two-thirds (648) of the bridges would lead to detours of two miles or less if they were closed. The greater the detour distance or the higher the vehicle count, the greater the benefit in replacing a bridge.

“One of the bridges we analyzed would’ve resulted in a detour of nearly 20 miles if it was closed. We know that’s not feasible. We also took into account whether closing a bridge would leave anyone without vehicle access to their property. In those instances, repairing or replacing a bridge is really the only option,” said Eric Fitzsimmons, postdoctoral researcher in civil engineering. Fitzsimmons, along with Steve Schrock, associate professor of civil, environmental and architectural engineering, co-authored the study. 

Due to the structure type of many of the deficient bridges or the type of deficiency, repairing the structure is not always possible, so options may focus on replacing or simply removing the structure. County administrators need to determine an economical plan to close or repair rural bridges while considering the safety of drivers. Low-water stream crossings are often considered by county officials but may not offer the desired level of safety for motorists.   

It’s hoped the research will aid county leaders in the planning and budgeting process.

“This study was designed to be a tool based on very simple data that county leaders can easily understand and use as they weigh the financial and political costs of closing or repairing a bridge,” Fitzsimmons said.



"Even on an ordinary Saturday, when I am pressed for time to complete the (at times) overwhelming amount of schoolwork I have, there are moments so extraordinary — like looking up at the sun through the mosaic of colored leaves on campus — that remind me why I love what I do and why I love KU." - Sam Henkin, first-year Ph.D. student in the Department of Geography, University of Kansas #exploreKU

The University of Kansas — Shaping those who shape the world Their feats are outstanding, extraordinary — even mythical. They are known as heroes. Discoverers. Innovators. Legends. But before they began shaping the world, they were each shaped themselves on a legendary Hill known as Mount Oread. And they all share one name that you should share too: Jayhawk. (See notable alumni at http://bit.ly/1qAGSaj)


One of 34 U.S. public institutions in the prestigious Association of American Universities
26 prestigious Rhodes Scholars — more than all other Kansas colleges combined
Nearly $290 million in financial aid annually
1 of 9 public universities with outstanding study abroad programs.
—U.S. News & World Report
46 nationally ranked graduate programs.
—U.S. News & World Report
Top 50 nationwide for size of library collection.
—ALA
$260.5 million in externally funded research expenditures
23rd nationwide for service to veterans —"Best for Vets," Military Times