Vibrocompaction Design in Repentigny: Deep Soil Improvement for Buildable Land

For a standard single-family residential parcel in Repentigny, the design package — including site investigation review, treatment grid layout, and verification protocol — typically falls between CA$2,050 and CA$4,100. Larger commercial or multi-unit sites requiring deeper treatment and more extensive testing generally range from CA$4,100 to CA$8,020, depending on the complexity of the soil profile and the number of verification points required.

Once we have the CPT or SPT data from the site, the design phase usually takes five to eight business days. This includes the analysis of pre-treatment conditions, grid layout, parameter selection, and preparation of the QA/QC plan. If additional site investigation is needed because existing data is sparse, that adds time for field work.

It depends on the fines content and the continuity of the silt layers. Sands with less than 10 to 12 percent fines respond well. Thicker, continuous silt seams act as vibration dampers and can prevent effective compaction. In those cases we evaluate whether supplementary techniques — like pre-drilling through the silt or adding water jets — can achieve the required density, or whether an alternative method like stone columns would be more reliable.

We specify a before-and-after testing protocol using CPT or SPT soundings at the same locations. The post-treatment test results are compared directly to the pre-treatment baseline. We look for a consistent increase in tip resistance and sleeve friction that corresponds to the target relative density. Acceptance criteria are defined in the design document before any compaction starts.

The vibrator does produce ground-borne vibration and audible noise during operation. In Repentigny's residential zones, we include vibration monitoring and setback distances in the design to keep peak particle velocities within municipal and NBCC guidelines. The treatment is relatively fast — a typical residential lot can be completed in one to two days — so the disturbance is short-lived.