U.S. Department of Transportation
Federal Highway Administration
1200 New Jersey Avenue, SE
Washington, DC 20590
James McMinimee, P.E., P.S.E.
UDOT Chief Engineer, Director of Project Development
My name is James Mcminimi. I retired from the Utah Department of Transportation in January of 2010. I am happy to be here to talk to you about prefabricated bridge elements and systems.
By the end of this Module, you will be able to:
First I would like to talk to you about Utah. In order to understand how Utah implemented prefabricated bridge elements and systems is important that you have a little background on Utah.
Utah the small state not geographically but demographically. Utah has about 2.5 million people, and a federal gas tax program of $350 million. The Utah Department of Transportation is a relatively small organization only 1650 people statewide. Interestingly, Utah has a relatively big transportation program. Utah’s current program is over 250 jobs, and over $2 billion under construction.
The Utah Department of Transportation is also different culturally than many DOTs. UDOT is a very customer driven culture. They are willing to take risks, and in the past, they have been willing to embrace new technologies. Utah has tried celery to bridge construction, accelerated pavement construction, a new technology called diverging diamond interchanges, and other innovative highway construction techniques. With all of that they also increased their partnerships, with industry, with local governments, and with resource agencies.
Balance of good price vs. other themes
UDOT has a set of department teams. Every project that Utah does considers these department teams in the effort to scope the project. These four themes are to accelerate delivery, to decrease and minimize detours or delays, to encourage innovation that speeds project delivery or provides value, and lastly to set a good price.
Obviously price is always a consideration and practically it works out that project managers really balance good price against the other themes. Again these themes are considered for every project.
The last big thing that differentiates Utah from many other DOT’s is this move to adopt a new business model. UDOT has moved away from the traditional business model that only considers construction cost when awarding projects. Utah’s model for award includes the idea that there are user costs associated with every project. This new business model adds together the construction costs and the user costs and the total of those costs are called project costs. CCU has moved from Lowe’s construction cost to lowest project cost. In this model societal costs are minimized and the Utah DOT has received much public praise, and also much political capital.
So here we are five minutes into the presentation and were finally ready to start talking about the lessons learned in implementing prefabricated bridge elements and systems. Remember the definitions of what PBES is?
First of all, it is innovative methods to decrease rich construction time. Second, usually you build the elements of the bridge off-site or outside of the traffic impacted area, and you transport them to the site and install or construct them as rapidly as possible.
UDOT has over 170 bridges total, completed or under construction that utilized ABC*
Moving along to one of UDOTs largest lessons learned. Utah developed this graph as a way to talk to with their transportation commission about what to expect with regards to costs as they implement this new technology. As the graph suggests the first time you try anything is the most expensive it’s ever going to be. And as you do more and more of the same thing it is typical to find that prices diminish. The misunderstanding of this graph has killed many a good idea. How many times have we as engineers asked about a new idea how much does it cost? And remove the item from further consideration because the first time it was built it was expensive? The truth is first implementations usually cost more but there is usually a giant potential for new methods to cost less. In the case of ABC there is a potential and time savings and there is also the promise of considerable cost savings. Utah had been keeping track of the costs to implement PBES, at the time that I left Utah the cost-benefit ratio of expense to user costs recouped was somewhere in the neighborhood of five or 6 to 1. That is for every dollar of investment in PBES, there were between five and six dollars in user costs recouped. Again a lesson learned and understanding and appreciation for this graph is very important when implementing PBES.
This graph shows a cost history of implementing full depth precast panels. UDOTs traditional cast in place deck used to run about $53 a square foot. When UDOT first bid for depth precast panels they came in at $63 a square foot. By the time they done 10 or 11 projects the costs have gone down to $37 a square foot. And according to a presentation that I saw recently from Carmen Swanwick who is UDOTs state bridge engineer, those costsÂ have held at about $37 a square foot.
7 Superstructures Constructed in a Single Location
Okay, so I slipped this picture in to remind everyone of the promise of PBES. This project is Utah’s innovate 80 project. It is an urban reconstruction project on I 80 in Salt Lake City. The picture is of what they called the Bridge farm. They constructed seven bridges and in the span of 41 days in the summer of 2008 installed all seven structures. The contractor claimed that by using this technique he saved 2 1/2 million dollars in constructing the bridges, and over a year in construction time. The user costs associated with that year were estimated at $25 million.
Utah was lucky and got to host the 2002 winter games. One of the legacies of that effort was risk analysis and identification of contingencies. On their website you doubt has posted a more comprehensive checklist of things you might want to consider if using SPMTs. The list I posted here is what I feel are the top five risks. The risks themselves aren’t important. What I’m trying to convey is that for any process that has a lot of risks that you should identify a plan for mitigating those risks. So a lessons learned or best practice would be to examine the risks for any PBES project, list those risks, and began working on ways to mitigate those risks.
In this slide I want to talk about innovation. As Utah has progressed with PBES, our contractors have begun to experiment and to suggest alternative methods. Simple things to help speed construction. This slide shows one such innovation. The right side we see tried and true Hillman rollers. A left side we see an innovative solution implemented by a contractor. The solution uses Teflon pads, steel channel, and lots of dishwashing liquid. It accomplishes the same thing as the Hillman rollers, at much less cost. The lesson learned is to allow innovation and experimentation.
Good little story-US first bridge move took 53 hours. The last SPM T. move was accomplished in less than 15 hours. Fast right? One of our contractors who is very innovative proposed an alternative method and that was slide in. The last slide in to less than six hours. Standing next to the superintendant as the bridge was moving he tells us "if you let me move it with traffic on it we can get it down to three hours!"
One of the first slides I talked about public support and political capital. This slide is all about public perceptions of PBES. These are real results from the 45th South project. Over 550 respondents. Normally when UDOT gets these surveys back about a third of the people like the project, about a third of the people don’t care about the project, about a third of the people hate the project. As you can see this graph is vastly different from that normal graph. In this graph about 94% of the people either gave the project a perfect score or one less than a perfect score. Amazing results. Customer focused. With these kind of scores from the public is it any wonder that politicians support this effort also? This alone is a great reason to do PBES projects.
Engage the industry A
Lastly, IF we want to do this we need to involve the entire industry. If we want to implement PBES, we can provide the leadership but we can’t do everything alone we need our partners to understand we need their help in implementing this exciting program. We need to make sure we engage fully both contractors and suppliers.
You should now be able to:
What are 3 best practices for implementing PBES