The construction phase of any project includes observation, engineering and administration. CNA engineers routinely manage this aspect of our wide variety of underground projects. We oversee construction for the owner or assist with the owner's project management. We provide construction observation, pay application certification, change order reviews, submittal reviews, and contract closeout administration.
Tunnel Rehabilitation Construction Engineering I
​This tunnel system consists of miles of storm tunnels, varying in size up to 16' wide by 15' tall, in a variety of shapes and construction materials. CNA was challenged to inspect and evaluate the 120 year old tunnel system, design tunnel liner repairs and replacements all to be completed the in an active tunnel. Construction administration included CNA observation, engineering and administration.
Tunnel Rehabilitation Construction Engineering II
​This 12' storm tunnel contained large voids outside the liner and cracks and holes leaking groundwater into the concrete liner. The project included rehabilitating two 2-mile sections. CNA inspected and evaluated the tunnels, designed liner repairs with appropriate construction methods for completing the repairs in an active tunnel. Construction observation, engineering and administration was part of the project.
Tunnel Rehabilitation Construction Engineering III
This tunnel was repaired in 5 phases and the construction phase required our team for tunnel observation, construction engineering and administration. This system consists of 2 miles of storm tunnel and varies in size and shape: horseshoe, round and box. CNA inspected, evaluated, and designed the improvements for the replacement.
