This ōban triptych depicts Minamoto Yoshitsune 源 義經 (center left) and his retainers after their victory over the troops of Minamoto no Yoshinaka at the battle of Hōjūjidono in 1184. The warrior monk Musashibō Benkei 武藏坊 辨慶 sits to the right of Yoshitsune. In the lower-right corner lie the decapitated heads of Nenoi Ōyata 根井 大弥太 and Gonrokurō 権六郎.

This report provides a simplified method to be used for evaluating the skin friction and tip resistance of axially loaded drilled shafts. A summary of literature and current practice was completed and then a comprehensive set of field and laboratory tests was performed. Several soil samples were collected from different sites from Arizona and surrounding states. Large scale direct shear apparatus was developed and used to determine the friction between soil and concrete. Finite element analyses were conducted on several prototype cases to determine effect of soil parameters such as dilation on the skin friction values. A step-by-step simplified approach was introduced to determine the skin and tip resistance of drilled shaft foundations in gravelly soils. An example application was presented to guide users in utilizing the simplified approach.