The expansion of the Faculty of Law building at the University of Toronto incorporated the addition of another story to the existing building. The increased loading required an upgrade to the capacity of the existing caissons. RWH Engineering Inc. (RWH) proposed an innovative solution to install micropiles next to the caissons to accommodate the additional loading.
The micropiles design required triple post-grouting to achieve the necessary bond between the grout and the soil. The soil encountered was comprised of layers of sand, silt, and clay. A sacrificial load test was performed to 250% of the ULS load.