FPrimeC Solutions was hired by KIEWIT-EUROVIA-VINCI (KEV) PARTNERSHIP to perform inspection and nondestructive evaluation of concrete culvert structure in Ottawa, ON. The culvert structure was crossing under Carling Avenue close to the existing Lincoln Fields bus station, Ottawa, Ontario. The main objective of the project was to evaluate the condition of concrete and identify structural details following an incident during the construction process at the LRT expansion project in Ottawa.
During the construction of drilled shaft, the culvert was partially impacted during the boring process, resulting in local damage to the culvert structure. The purpose of investigation was to perform concrete scanning to determine rebar detailing, and assess quality and structural integrity on and around the damaged section.
In order to help client with the assessment of structural integrity, and evaluating rebar pattern, a systematic test procedure was defined and implemented to collect quality data on the condition of concrete around the damaged section. The structure was inspection by FPrimeC Engineers. Close Up visual inspection and hammer sounding was used to identify the test area, and the extent of potential defects.
Nondestructive Evaluation of Culvert
Different NDT methods were used to assess quality and integrity of the concrete culvert.
- Impact-Echo method was used by FPrimeC engineers to assess the thickness of concrete elements with one side access.
- Ground Penetrating Radar (GPR) was used to assess the location, spacing and pattern of steel bars in the walls, top slab, and the gusset area.
- Ultrasonic Pulse Velocity (UPV) was used to assess quality of concrete near damaged areas.
- Rebound Hammer (Schmidt Hammer) was used to verify concrete strength, and uniformity of concrete.
The NDT evaluation allowed the FPrimeC engineers to evaluate the concrete strength of the concrete areas. It also allowed for the estimation of the thickness of the concrete elements through the use of Impact-Echo method. Meanwhile, the GPR allowed the structural detailing of the reinforcing bars by scanning the elements. Altogether, this gave an approximate evaluation of the extent of the damage on the concrete culvert brought about by the drilling incident.