NCDOT I-40/440 Design-Build
CLIENT: North Carolina Department of Transportation
The NCDOT contracted this Design-Build project with Granite Construction Co., based in Watsonville, Calif., and RS&H, a Charlotte engineering firm for this 11.5-mile section of the I-40/440 Beltline across South Raleigh. This teaming used Vaughn & Melton Consulting Engineers as a sub-consultant to provide utility coordination, railroad coordination, surveys and SUE, and right-of-way acquisition.
This project was designed so that three lanes of the I-40 section stayed open in each direction during construction. The first work focused on rebuilding I-440 on the Beltline’s southeast corner, from the I-40 split (Exit 301) to the U.S. 64/264 exit in East Raleigh. Major construction on the busier I-40 section, from U.S. 1/64 at Cary to the I-40 split, started in late 2014. The project completed in August 2016.
The contractors dug out and replaced all the existing pavement – a 2-foot depth of concrete slabs topped with asphalt – because the 30-year-old concrete was deteriorating due to a chemical process called alkali-silica reaction which caused the underlying concrete to expand and crack during the past three decades.
V&M provided additional surveys for the design-build team including railroad surveys, bridge clearance and structural surveys for bridge widening additional topo surveys for a DDI interchange at South Saunders St. plus additional hydro surveys. SUE work consisted of the designation of all utilities at S. Saunders St.
Railroad coordination consisted of acquiring the required rights of entry on 3 railroad lines, two owned and operated by NS, and one owned by NCRR and operated by NS for the bridge widening and deck rehabilitation of 5 bridges and one road underpass. These rights of entry were acquired within 7 months.
Utility coordination required V&M to get Progress Energy to relocate one existing overhead power line crossing I-40/440 at a bridge scheduled to be widened plus additional minor relocations of power, telephone, and CATV. V&M also designed the reconstruction of approximately 300LF of 18” gravity sewer where 50 feet of fill was proposed to be placed over the existing main. As there were no means to determine whether the existing pipe would support the additional loading, it was determined this section of pipe needed to be rebuilt along with a manhole which exceeded 50’ in depth. V&M proposed that the 18” DI pipe be placed within a 1’ thick, 60” steel encasement pipe to support the fill loading. This encasement pipe was installed by jacking and tunneling through the existing fill of I-40.
The plan also included four miles of what the engineers call auxiliary lanes, linking the on- and off-ramps at the U.S. 1/64, Gorman Street and Lake Wheeler Road exits. That reduced the need for some drivers to weave in and out of the exit lanes, and DOT engineers say it improves traffic flow.