A STUDY OF THE FACTORS INFLUENCING THE PENETRATION AND CAPACITY OF VIBRATORY DRIVEN PILES

Abstract

This study examined the factors influencing the vibratory installation of piles in drained granular soils. Several variables were examined to assess their relative importance in pile installation by simulating the pile-hammer-soil system using the finite difference program, FLAC. The soil was modeled using an elasto-plastic hyperbolic stress-strain model. The variables investigated include : soil strength, pile-soil interface friction angle, lateral earth pressure coefficient, hammer operating frequency, bias weight, hammer centrifugal force, and pile embedment. A simple empirical relationship was introduced to estimate the ultimate axial load capacity of vibratory driven piles based on hammer, pile and penetration characteristics. The capacities estimated using the proposed relationship are compared to other formulas using the results of this study and to data from two field test projects.