DRAINAGE PILES: A METHOD FOR INCREASING THE AXIAL CAPACITY OF FRICTION PILES.

Describes a method for increasing the axial capacity of friction piles embedded in clay soils. the proposed method consists of increasing the shear strength, and consequently the soil-pile adhesion, of the soil around a pile. This is accomplished by draining water from the surrounding soil into the pile. Equations are developed to predict the maximum pile capacity, and Terzaghi's theory of radial consolidation is used to predict the variation with time of the bearing capacity during the drainage process. Results from preliminary laboratory tests that demonstrate the feasibility of the drainage pile concept are described, and practical considerations that need to be investigated in greater detail are discussed.