Ali Bouafia

Load-settlement behaviour of socketed piles in sandstone

Nine Static vertical pile loading tests were carried out in Abu-Dhabi, the United Arab Emirates in order to assess the end bearing capacity and settlement of piles bored in slightly silty sands overlying soft rocky horizons like sandstone and calcarenite. The paper is aimed at presenting the results of interpretation of the pile tests in order to estimate the end bearing capacity in correlation with the unconfined compressive strength Rc and the rock quality designation (RQD). Load-settlement behaviour is also studied through an analysis by the elastic methods commonly used in pile design.

Development of Semi Empirical Method for Predicting Axial Pile Capacity

This study aims to estimate the axial pile capacity through the use of semi empirical analysis based on limit equilibrium theory and SPT data. An interesting alternative for improving the quality of bearing capacity prediction from the rational methods of plasticity is the definition of the required mechanical parameters, by correlation with those obtained from in-situ tests. In this context, Aback-calculation of mechanical parameters required by the numerical method has been carried out for calibrating the calculated limit vertical load to the interpreted load tests. It is established through the incorporation of approximately 60 data sets of pile loading tests on driven piles in sandy soils obtained from data published in the literature. Consequently, base and shaft resistances factors are estimated. The assessment of the predictive performance of the new method against a number of traditional SPT-based approaches indicates that the developed method can be used as an alternative for determining the bearing capacity of piles in geotechnical practice. For practical purposes, the end and shaft bearing resistances factors were proposed in relation with the N-SPT value.