SPT-based Methods for Estimating Installation Torque and Capacity of Helical Piles

Helical piles are extensively used across Canada in various engineering applications. Current design methods estimate the axial capacity of helical piles using soil strength parameters when site investigation is available. Alternatively, helical piles can be designed from an empirical torque correlation when installation torques are available. However, it will be more valuable to the industry to have direct design approaches based on geotechnical site investigation. Greentown Homes Ltd., the industrial partner in Edmonton, has built numerous foundations using helical piles in various soil conditions in Alberta. For the proposed project, the intern will first supervise in-situ pile installation of building foundations, record torque values, and collect geotechnical properties of soil at different sites. The intern will compile and analyze the Greentown database of site investigation and installation torques. Using the Greentown and other databases, the intern will develop an empirical method for helical capacities based directly on the SPT, and an empirical correlation between the torque and SPT blow counts.

Yiwen Zhang
Faculty Supervisor: 
Lijun Deng
Partner University: