A semi-empirical model for the overturning capacity of directly embedded foundations

Directly embedded foundations have long been used by electrical utilities for power lines with wood or steel poles. A “rule of thumb” approach of “10% length plus 2ft” has usually been used to design directly embedded wood poles. While the approach works well in overall from the past experience, its ignorance of the effect of soil and pole properties leads to an inconsistent design: either overly conservative or too risky. In an attempt to find a better alternative, a semi-empirical model is described in this paper for proper determination of the lateral capacity of a directly embedded foundation. The model is validated against available experimental data in the literature. The model is applicable to any directly embedded poles, regardless of wood, steel, or concrete.