A complex highway or bridge replacement project can have significant impacts on a community that extend well beyond the work zone. The Transportation Management Plan (TMP) process, which is required on federally funded projects, has focused time, attention, as well as investment to accommodate motorists, and more recently bicyclists and pedestrians during construction. The TMP recommendations may include global signing plans, minor or major detours, posted alternative routes, and diversion to other transportation modes within the broader corridor or region.
Steps to a successful plan
The work zone traffic control plan for a major project requires input from all team members. First, the project manager identifies the major work items and develops a critical path schedule to determine the project timeline and if multiple seasons are required to construct the project. In most scenarios, the critical path is set by the bridge work which generally has the longest durations and the biggest demands for traffic control. If a bridge is replaced or widened the Engineer will need to plan for removal of existing structures, driving of piles, installation of temporary construction items such as shoring and cofferdams, and highway closures to facilitate beam removals/placements.
Next, the Engineer analyzes potential construction sequences, develops staging scenarios and associated traffic control concepts. This analysis also incorporates a cursory review of other projects under construction in the same season. The team tests the alternatives with respect to constructability, cost estimating and operational analysis. Minimizing the number of stages keeps traffic control setup time and overall costs down. However, the design team should also take time to identify ways for the contractor to complete advance work adjacent to or under the current facility without needing lane closures, eg drainage, pile installations and foundations. Further, identifying alternative bridge types and accelerated construction methods such as using pre-cast concrete elements can shorten work stages. Moving lane closures to nighttime or weekend hours is another method to keep traffic moving during peak hours and minimize excessive queues.
Finally, the TMP is intended to be a living document that begins in design and evolves throughout construction. Constant monitoring of actual travel time through the work zone allows the Engineer to check assumptions and make improvements for safety and mobility. For major projects, a comprehensive public information plan keeps stakeholders apprised of work and allows owners to advise motorists of traffic conditions and upcoming changes to work zone configurations.
Bettering our expertise, benefitting the future
Highway construction projects are a necessary part of improving and maintaining good infrastructure. At M&M, our engineers incorporate knowledge from past projects to improve constructability of future projects. M&M understands that early investment of time and energy in design, envisioning how a project will be constructed, streamlines construction time in the field and positively impacts mobility.