Transform I 66 – Outside the Beltway I 495

Fairfax County, Virginia

Transform 66 Outside the Beltway is a public-private partnership that will expand Northern Virginia’s Interstate 66 into a greatly enhanced multi-modal corridor. Express lanes are scheduled to open in December 2022.

DECON provided structural analysis and evaluation of the existing bridge on Nutley Street over I 66 and VMATA, and State Bridge No. 1163 in Fairfax County. The bridge has three curved simple supported steel girder spans of 138, 54, and 138 FT. The existing bridge was built in 1986 and designed with AASHTO Standard Specifications for Highway and Bridges 1983 interims 1983 and 1984 and VDOT Modifications. The structural analysis was performed to assess the current capacity of the bridge under AASHTO LRDF Bridge design specifications 7th Edition, 2014 with 2015 Interims and Live Load HL93.

The structural evaluation included analysis of the connection of a T-ramp (the I 66 WB Express Ramp to Nutley Street) on the east side of the existing bridge Span No. 1 and very close to Pier No 1. DECON provided recommendations for the proper jointless connection of the new T-ramp to the existing bridge. DECON analyzed the existing substructure and foundations to determine its capacity to receive additional loads coming from the T-ramp. DECON provided an Estimated Bill of Quantities for the recommended repairs.

DECON prepared construction documents, design plans and structural engineering reports for more than six miles of ground mounted post and panel sound walls, and more than two miles of retaining walls using MSE walls, cantilever reinforced concrete walls, post and panels, and tied-back soldier piles.

DECON also prepared construction documents for several ancillary roadway structural elements, such as temporary shoring systems for bridge and retaining wall construction, overhead bridge signs, overhang bridge deck brackets, false work and formwork for pier construction.