Rapid Impact Compaction – 1600m²

This project involved the improvement of the foundation soils for a proposed townhouse
development at 3700 Downpatrick Road in Ottawa, Ontario. The site was formerly used for
commercial space that was subsequently demolished and the site backfilled. Due to the poor existing ground conditions, it was required that ground improvement be carried out in order to support the proposed buildings. Nearby homes  and commercial buildings required that the work
be monitored extensively for vibration.

Geopac proposed a ground improvement program of Rapid Impact Compaction (RIC) to compact
the fill with the objectives of improving the bearing capacity, mitigating liquefaction, and
controlling settlement. The work is to be split in two phases, with the second phase set to take
place spring of 2015.

The soil on site consists of approximately 4 to 5 meters of fill, typically sand or silty sand with
some granular material. Underlying the fill is a native clayey silt till. The water table was found to
be approximately 2 meters below the ground surface. Prior to the start of compaction works, the
working platform was prepared with pavement, debris and organic matter stripped from the site
and disposed of.

Based on Geopac’s design, the 1600 square meter platform was compacted in four phases. The
RIC program was completed ahead schedule, with all SPT and PMT tests achieving results above
requirement. Geopac delivered a value engineering solution of soil improvement providing a
cost-effective reliable method of ground improvement appropriate for the project and for the site.