ASPIRE is a quarterly magazine published by PCI in cooperation with the associations of the National Concrete Bridge Council. The editorial content focuses on the latest technology and key issues in the Concrete Bridge Industry.
Issue link: http://www.aspiremagazinebyengineers.com/i/657823
14 | ASPIRE Spring 2016 The value and benefits of accelerated bridge construction (ABC) are often easier to distinguish and realize in urban environments characterized by high traffic volumes, congestion, and greater roadway densities. In these areas, ABC dramatically reduces work-zone, road- user costs. This coupled with other project costs including right-of-way acquisition (ROW), project administration, environmental permitting, and utility relocation, or lack thereof, often results in lower project costs making it an easy sell to lawmakers, the public, and other stakeholders. Moreover, at a time when many of our urban highways are over capacity and customers have come to expect a reliable transportation network, building and maintaining support for efficiently preserving our highway assets can be easier with ABC, especially when detour routes are short. However, in rural states like Vermont, it can be harder to justify the value of ABC where daily traffic volumes and associated roadway user costs tend to be low. In addition, roadway networks are scarce, which results in lengthy detours, making it difficult to garner public support. So what is the value of ABC and how should its value be measured? Like other states, many of the typical b e n e f i t s h o l d t r u e re g a rd l e s s o f geography. For example, by closing a road rather than installing a temporary b r i d g e , i m p a c t s t o r i g h t - o f - w a y, environmental resources, and utilities are reduced or eliminated altogether, facilitating expedited project delivery and rapid replacement of deteriorating infrastructure. With Vermont's lengthy environmental permitting and ROW processes, the use of ABC substantially reduces the time it takes to deliver bridge rehabilitation and replacement projects, ultimately lowering design costs and reducing resource demands. Short-term road c l o s u re s a l s o i m p ro v e s a f e t y f o r motorists and construction workers alike by routing traffic around rather than through the work zone. Vermont Agency of Transportation's (VTrans') mission, like many other t r a n s p o r t a t i o n a g e n c i e s , i n c l u d e s providing for the safe movement of people and goods. VTrans' Structures Section recently adopted a general rule of considering road closures as the preferred option for maintaining traffic unless deemed impractical during the project initiation phase. While not always obvious, short- term road closures also minimize impacts to the traveling public and commerce by significantly reducing on-site construction duration. Results from a public survey following three consecutive rapid bridge replacement projects on VT 73 in 2014 showed that 82% of respondents felt very satisfied with ABC even though the detour length was 51 miles over mountainous terrain. In 2012, VTrans created the Accelerated B r i d g e P ro g r a m ( A B P ) . S i n c e i t s inception, VTrans has reliably expedited project delivery and reaped many of the common benefits attributed to ABC. This success has added unanticipated value by becoming ingrained in our o r g a n i z a t i o n a l c u l t u re p ro m o t i n g innovation throughout all phases of project delivery. In addition, the ABP has gained significant support from local politicians and, with this support, has been able to pass legislation that further enables and promotes the According to a Vermont Agency of Transportation survey, 45% of respondents found a 10-day closure acceptable. All Photos and Figures: Vermont Agency of Transportation. What would be the maximum acceptable length of closure for Bridge #33? A. 5 days B. 1 week C. 10 days D. 2 weeks E. 4 weeks A B C D E How would you rate your level of satisfaction with the road closure compared to alternating one-way trafc following the bridge closure period? I preferred the road... I preferred the alternat... Answered: 108 Skipped: 7 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% Survey respondents overwhelmingly preferred short, total road closures to longer, alternating one-way closures. by Jennifer Fitch, Vermont Agency of Transportation The Value of ABC A department of transportation perspective from Vermont P R O J E C T