Providing oversight for the safe and accurate construction of a major thoroughfare that impacts thousands of travelers is a complex job and a critical aspect of ensuring a project’s success.
DRMP had the honor of providing construction engineering inspection (CEI) services for the first and now second phase of the $276 million I-40/I-77 Interchange Improvement Project in Statesville, N.C. – an essential component of North Carolina’s highway system.
The I-40/I-77 project is the largest project in North Carolina for which DRMP is providing construction services. It has been a phenomenal teaching and training opportunity for some of our staff to learn the CEI side of our business.
Pictured in the background is the newly opened I-40 westbound to I-77 southbound 2,600-foot flyover bridge, making an easier transition onto I-77 southbound.
The North Carolina Department of Transportation (NCDOT) design-build project will improve traffic congestion and enhance safety for the interchange.
Our expert CEI team is responsible for monitoring the daily operations of this project to make certain it is completed in accordance with the design plans and specifications.
The first phase of the project – started in 2012 and completed in 2018 – involved widening I-40 from four to six lanes in each direction, from Radio Road to the east to Old Mocksville Road in North Carolina. The second phase focuses on collector-distributor lanes on I-40 eastbound, widening I-77 from Exit 49B to north of the I-40 interchange. It also entails the construction of a partial turbine interchange at the intersection of the two interstates. Phase 2 is projected for completion in Spring 2024.
Built in the 1960s, the antiquated interchange was designed to provide capacity for a maximum of 5,000 vehicles per day. Today, the interchange sees more than 70,000 vehicles a day, with traffic projections expected to reach 100,000 per day by 2035.
Recognizing and Overcoming Challenges
The design-build project will continue the interstate widening on I-77 from a four-lane to an eight-lane facility that will include 14 new structures. The project also involves modifying the I-40/I-77 interchange to a turbine design, which will include a 2,600 foot long, elevated flyover bridge.
A vehicle travels on the newly opened I-40 westbound to I-77 southbound 2,600-foot flyover bridge. In the background is the newly constructed I-77 southbound to I-40 eastbound loop ramp, which is the only loop ramp that will remain in the modified turbine design.
DRMP is the prime CEI consultant on this project, and we are working with subconsultants RK&K and AMT Engineering. There are more than 22 inspectors evaluating concrete and asphalt paving; soil-cement stabilization; erosion control; survey grade verification; bridges; mechanically stabilized earth (MSE) and sound walls; and materials sampling and testing.
As with any interstate project, the No. 1 priority is the safety of the workers and the traveling public. Our technicians are on-site constantly monitoring traffic control and safety measures to ensure they are in place and stay in place throughout the duration of the project. There have been multiple lane shifts on the project, which must be carefully planned, constructed, and delineated in order for motorists to safely navigate them.
Looking over I-77 southbound approaching the new bridge over I-40, to the left is the new steel girder flyover bridge from I-40 eastbound to I-77 northbound.
There are also erosion and sedimentation control challenges associated with this project. In lieu of typical embankment construction, a 2,600-foot-long flyover bridge was constructed to reduce the environmental impacts to a wetland area within the project. Barges were also strategically placed to allow for construction to be performed with minimal impact.
Another difficult challenge is overseeing the safe construction of structures being erected over traffic. We must ensure extra safety measures are in place, so nothing falls off the bridge during construction and lands in traffic.
A Priceless Experience
This is much more than an interchange project. There are miles and miles of highway being constructed due to the additional lanes and ramp lengths of the turbine interchange.
When this project is complete, the interchange of I-40 and I-77 and the two primary access roads (US 21 and East Broad Street) will provide much needed traffic relief and safety for motorists while modernizing the intersection.
Pictured is the removal of the old I-40 westbound Clover Leaf Loop to I-77 southbound and all new I-40 concrete pavement.
This is an example of a great training experience because it encompasses every discipline on a construction project. It’s allowed our professionals to become cross-trained in different areas of expertise and to receive certifications in Conventional Density Testing, Aggregate Base Course Sampling, Concrete Field Testing, and Chemical Stabilized Subgrade, to name a few.
The wealth of knowledge and experience our team has gained from a project of this magnitude has been priceless. We’re introducing new people to the CEI side of the business and specifically hiring them to work on this project, which in turn provides a benefit for the client and future clients. This kind of experience gives our staff a well-rounded perspective on successful project outcomes.
