Stone Columns - Boychuk & Mcormond

First the stone columns were pre-drilled to a depth of 6m using a SoilMec SR-30 to partially set temporary casing, then the casing was driven to the required 11m depth using a crane mounted vibratory hammer. DSD utilized its Liebherr HS855HD crawler crane to hoist and drive the temporary casings. Each of the stone columns were excavated out using a Liebherr LB28 drill rig and then backfilled with specified granular material which was compacted by vibrating the temporary casing. Further compaction of the stone column as required was done with a vibratory lance. DSD completed 450 stone columns with diameters of 1800mm and 2100mm and an average depth of 14m.

Due to the project being only a few meters away from the existing major road ways, extreme safety measures were taken. DSD worked with PCL on the pre-project planning to ensure no steps were missed and everyone was on the same page. The successful execution of this project provided improved slope stability and bearing capacity for support of the MSE Walls, reduced magnitude of settlement and increased settlement rates of the embankment construction.