Transform I-66 Outside-the-Beltway

Innovative solutions for an important transportation corridor

The Transform 66 Outside-the-Beltway project is part of the corridor’s broader transformation to multimodal use and enhanced reliability. The project is a public-private partnership (P3) between the Virginia Department of Transportation (VDOT), the Department of Rail and Public Transportation (DRPT) and private partner, I-66 Express Mobility Partners. In addition to roadway reconfiguration and intelligent transportation systems (ITS), Transform I-66 Outside-the-Beltway includes new bridges and ramps.

Innovative, sustainable pavement design

EXP’s team designed the pavement structure for new construction, reconstruction and widening of express lanes, shoulders and ramps throughout the 22.5-mile corridor. The designs spanned over 53 widening/new construction pavement sections and over 80 rubblization and build-up sections.

EXP provided designs using an innovative approach of rubblizing the existing concrete, salvaging existing pavement layers and overlaying with asphalt as an alternative to complete reconstruction. Recycled crushed concrete as base material was recommended as an economical and environmentally-friendly alternative.

The construction team calculated that use of rubblization reduced approximately 21,500 truck trips on the project. These savings were realized by eliminating the need for reconstruction, which would typically require hauling out existing concrete and bringing new material to site. Additionally, the use of recycled crushed concrete reduced the need for new base material by 166,000 cubic yards, eliminating significant waste. These innovative methods had a significant impact in reduction of CO2 emissions.

Bridge and wall design along the corridor

The EXP team designed three critical bridges along the corridor: I-66 WB over Route 645 (String fellow Road), I‑66 EB over Route 645 and I-66 EBCD over Route 645. The bridges are simple span prestressed concrete bulb-tee girder bridges supported by full integral abutments on rock-socketed steel H‑piles.

The I-66 WB over Route 645 bridge has shared use paths separated from I-66 travel lanes by traffic barriers. EXP performed drainage analysis (using design rainfall intensity and proposed storm water discharge) to evaluate the need for inlets on the bridge decks.

The EXP team expedited design of 8,400 feet of retaining walls. Design encompassed cast-in-place concrete cantilevered retaining walls, post and panel retaining walls, MSE walls and ground-mounted sound walls (noise barriers) over 20 feet in height.

Services

Bridge Design, Wall Design, Structural, Drainage, Stormwater Management, Pavement Design