This project consisted of the construction of an underpinning system for the Information Sciences area of the hospital. Expansive pyritic shales were identified to be causing structural damage to the building and disruption of day to day business.
CMT developed a design approach to underpin the main bearing wall with a cantilevered micropile system and utilized the friction capacity of micropiles to design tie-downs to the spread footing foundations.
The goal was to provide a reasonably costeffective method of creating distance between the structure and the underlyingpyritic shales, since it was unknown how much additional expansion would occur. Underpinning the conventional foundations wasthe only viable option. The underpinningconsisted of installing two (2) micropiles on one side of the wall. Essentially, the far micropile acts intension and the near micropile acts in compression.