College of Architecture and Environmental Design
Architectural Engineering Department
BS in Architectural Engineering
This study is concerned with the comparison of driven and screw piles when exposed to lateral forces and the effects of gapping on stiffness and displacement. Stiffness contributions were determined from force-displacement profiles, gap depth formation curves, strain profiles, bending moment profiles, and P-Y curves. Driven piles were found to be about twice as stiff as screw piles at lower displacements. At larger displacements, the stiffness of the two pile types start to converge. When the piles are in full contact with the soil, stiffness contribution is derived from both the soil and the pile. When gapping is exhibited, the soil stiffness contribution is minimized, increasing deflections. Large initial displacements of the piles cause all subsequent forces to incur greater deflections in the pile head than expected.