Box culvert abandonment using cellular concrete in Alexandria, Virginia
As part of an interchange upgrade, a new double box culvert was constructed. After the new box culvert was commissioned, the original single box culvert needed to be abandoned in place. Access to the box culvert was only available from one end, and there were multiple sources of active water infiltration into the box culvert.
VDOT standards specify a minimum compressive strength of 50psi for pipe & culvert abandonments. The proposed mix design needed to meet or exceed 50psi.
The customer wanted lump sum pricing, so all sources of infiltration (potential leaks during grouting) had to be completely sealed prior to abandonment material placement.
Due to the length of the culvert (350 feet), the material used for abandonment needed to be easily pumped up to 450 feet. Due to site constraints, material needed to be pumped 100 feet to reach the open end of the box culvert.
Cellular concrete is easily pumped long distances, so pumping 100 feet to reach the placement location, and then up to an additional 350 feet to the far end of the culvert wasn’t a problem.
To address water infiltration into the box culvert (potential leaks during grouting), polyurethane grouting was proposed for plugging pipes entering the box culvert, and sealing around a 48 inch HDPE pipe which was run through the culvert to tie an intersecting pipe into the adjacent, new box culvert.
CJGeo abandoned the pipe in place using lightweight cellular concrete. CJGeo self-performed all polyurethane grouting for making the structure watertight, placed all sacrificial placement pipes, and generated and placed the cellular concrete to complete the box culvert abandonment.