Major Interstate Bridge Project in Delaware

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Mabey Supports Bridge at I-495

Mabey Supports Bridge at I-495

Contractors remove damaged piers one piece at a time

Contractors remove damaged piers one piece at a time

MAT75/125 Towers

MAT75/125 Towers

Mabey towers enable bridge to remain in service during repairs

Mabey towers enable bridge to remain in service during repairs

  • Transportation
  • Propping and Shoring
  • Wilmington, DE
  • March 2015

Speak to a specialist

Jim Porreca

Bridging & Propping Specialist | Pittsburgh Depot

1 (412) 475-6087

Challenge

The I-495 bridge over the Christina River in Wilmington, Delaware, was discovered to have severely leaning piers. Delaware DOT described the north and southbound lanes as “tipping dangerously.” It was determined that 55,000 tons of dirt stockpiled near the bridge by a contracting and hauling company had created compression around the foundation and compromised the integrity of the structure. After further investigation, engineers concluded the support piers under the bridge were damaged and in need of immediate repair, abruptly closing the bridge and cutting off access for 90,000 commuters. The road closure caused major traffic delays and congestion and needed to be reopened quickly — however, safety remained the priority.

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Solution

J.D. Eckman Contractors met with DelDOT and other agencies in an emergency meeting to create a recovery plan. Engineers from AECOM, J.D. Eckman, DelDOT, FHWA and Mabey were involved in decision points for the plan. Mabey supplied a total of 32 MAT75/125 towers, support beams, support tower grillage beams, and L/N cylinders. The tower system is capable of supporting approximately 200,000 lbs per leg, and the adjustable screw units can be placed on the tower legs to help with leveling and height adjustment.

“Mabey had the equipment to best fit our needs for this job. The MAT75 tower can be made five feet wide and the grade beam was only six feet wide, so the Mabey towers fit within the dimensions of the grade beam we were using.”
– Joseph Rovnan, PE, J.D. Eckman Contractors

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Results

With Mabey’s towers safely installed and the bridge stabilized, the bridge was reopened to traffic — a month ahead of schedule — while construction on the bridge piers proceeded. This massive project began in June 2014 and was completed March 2015 and won Delaware’s ACEC 2015 “Conceptor Award” for Engineering Excellence. Mabey is proud to be part of this success story.

Read the article as it appeared in Roads & Bridges Magazine.

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