Beginning on Monday, March 14th, work crews will begin construction activities in preparation for the upcoming replacement of 14 deteriorated bridge superstructures on I-93 in Medford.
The $98.1 million project is funded through the Patrick-Murray Administration’s historic $3 billion Accelerated Bridge Program to reduce the Commonwealth’s backlog of structurally-deficient bridges. The project known as “93Fast14” is using an innovative approach that will expedite the work, with major construction in June-August and completion in 2011.
The preliminary work commencing next week will focus on the construction of temporary median crossovers at the northern and southern limits of the project. These crossovers will be used during the majority of weekends this summer to allow the bridge replacement activities to occur.
The following overnight lane restrictions are scheduled for next week:
I-93 Northbound
Monday evening, March 14th- Thursday morning, March 17th, 8:00pm-5:00am– The left lane will be closed in the area beyond Exit 29 (Routes 28/38) near the Somerville/Medford line.
Thursday evening, March 17th- Saturday morning, March 19th, 8:00pm-5:00am- The left lane will be closed in the area beyond Exit 33 (Route 28) near the Medford/Stoneham line.
I-93 Southbound
Monday evening, March 14th- Wednesday morning, March 16th, 8:00pm-5:00am– The left lane will be closed in the area beyond Exit 30 (Route 38) near the Medford/Somerville line.
Wednesday evening, March 16th- Saturday morning, March 19th, 8:00pm-5:00am- The left lane will be closed in the area near Exit 30 (Route 38) near the Medford/Somerville line. A second left lane will be closed on these evenings in this same area between 9:00 PM and 5:00 AM.
Thursday evening, March 17th- Saturday morning, March 19th, 8:00pm-5:00am- The left lane will be closed in the area prior to Exit 33 (Route 28) near the Medford/Stoneham line.
Appropriate signs, channelizing devices and traffic control measures will be used to guide drivers through the work zone. MassDOT encourages drivers to allow extra time for their trips and to reduce speed and use caution when travelling through the work zone.
The “93Fast14” is using an innovative design-build procurement process to accelerate project development, enabling construction to begin quickly. To minimize traffic impacts and streamline construction, the project features modular bridge technology, enabling much of the work to be performed off-site. The bridge replacement units will be built at remote fabrication facilities and then shipped to the site. During a series of ten weekends between June and August, the replacement units will be put into place using heavy lifting equipment. In order to demolish the existing bridges and replace them with the new units, MassDOT will close the necessary bridge location and cross traffic from one side of I-93 to the other, maintaining two lanes of traffic in each direction at all times. The rapid construction techniques employed by MassDOT will allow all travel lanes to be fully reopened each Monday morning.
For more information or to sign up to receive future updates and schedule information, visit the project’s website at www.mass.gov/massdot/93fast14 .
How long will the prep work last and will people be notified 24 hours in advance if a road below the bridge will have to be closed, such as Webster street, Salem street or valley street?
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The prep work will continue until actual weekend heavy construction begins in June. We will provide updates each week and more often as necessary regarding all street and lane restrictions. Thanks.
Posted by: A.B. | March 17, 2011 at 09:24 PM
Can you give us more info on how you intend to achieve this fast turnaround. Are you building the bridges to the side then sliding them over like you did on Rt2? Or are you using some other method?
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Thank you for your interest in the 93 Fast 14 project. You posed an excellent question.
By using innovative construction practices, we will be able to complete this project much more quickly than we could if we were to use conventional construction methods. In order to accomplish this, MassDOT’s contractor will replace each existing bridge superstructure (concrete deck and steel beams) with several modular bridge units which will be fabricated off-site and trucked in for the project. Each modular bridge unit will be made of a concrete deck on top of two steel beams, called stringers. When they arrive on-site they will be ready to be put in place by crane. Crews will erect the replacement superstructure by hoisting and lowering each modular unit into place. There will be gaps between each modular unit. Once the units are in their final location, crews will pour a special concrete mix in the gaps between units. Since it closes the gaps, this connecting concrete is referred to as a ‘closure pour’. The concrete mix crews will use for the closure pour has been specially designed to cure rapidly. Once the concrete cures, crews will paint temporary lane markings and install a barrier system. The bridge will then be ready to be reopened for vehicular use.
Crews will be performing other preparatory and finish work outside of the weekend bridge replacement work hours. Such work includes preparing the bridge seats for the modular units, substructure repairs, surveying, and utility work. Finish work will include installation of parapet walls, paving, and final line striping.
In comparison, conventional construction methods would necessitate long-term lane closures. Work would occur on one lane at a time. The bridge superstructures would be demolished and replaced piece-by-piece with cast-in-place concrete. It would take at least four years to complete this work using conventional construction methods. By using accelerated bridge construction techniques, the bridges will be completed in a single construction season. Although the use of prefabricated modular bridge units is innovative, it is a proven technology that has been used to rapidly replace bridges in many locations across the country.
This project is part of the Accelerated Bridge Program, which serves as MassDOT’s ‘laboratory of innovation’. The Accelerated Bridge Program is implementing several cutting-edge bridge construction technologies in order to improve Massachusetts’ infrastructure rapidly, safely, and efficiently while causing the least possible construction-related impacts to road users and communities.
Posted by: Dan | March 17, 2011 at 07:30 PM