Advanced modeling tools for the analysis of axially loaded piles

Pile foundations have been used in construction for thousands of years but only in the last few decades has there been significant progress in the technology of pile installation. This progress has not been matched by progress in the analysis and design of these foundation elements. This is in large part due to considerable difficulties in analyzing both pile installation and the response of piles to various types of loadings rigorously. Given these difficulties, the profession has in general used relatively crude design approaches. This is likely to change due to pressures from different directions, particularly the progress in code design (the push towards load and resistance factor design in geotechnical engineering requires a much better grip on all the factors that need to be considered in calculating pile resistances and what the uncertainties in quantities and analyses are, requiring sounder analytical frameworks) and economics (materials costs have started to rise, a trend that, if continued, would make it more economically interesting to have optimal designs). In this paper, we will examine the design process for axially-loaded non-displacement piles, focusing on assessing the strength of the underlying analyses. We will show that, for these types of piles, design can be placed on a theoretical basis. We will discuss on-going research on pile analysis that is contributing to the gradual development of the new design methods.