Comparison between measured and predicted values of axial end bearing and skin capacity of piles bored in cohesionless soils in the Arabian Gulf Region

The axial base and skin capacities of piles bored in cohesion less soils are often estimated using empirical, semi-empirical and theoretical methods. The aim of this paper is to assess the applicability and evaluate the accuracy of different predictions methods available in the literature, via comparison with data from 43 field pile load tests conducted on shafts drilled in the region of the United Arab Emirates. Janbu's theoretical method (1989) with the parameter (=75°) and Vesics theoretical method (1975) yielded accurate predictions for the base resistances. Burlands approach (1973) overpredicts the skin capacities with an average predicted-to-estimated ratio (q _p /q _e) of three times greater than the unity while using values of the coefficient of earth pressure (k=05k _o ) and the angle of soil-pile friction (=23).