Capacity of axially loaded bored cast-in-place piles socketed in Dubai limestone

Piles are used as the foundation of choice in various engineering projects including multi-story buildings, bridges and offshore structures. This paper analyzes the axial capacity of bored cast-in-place rock socketed piles from eight full-scale load tests in Dubai. Two of the tested piles are instrumented providing data about the load transfer along the pile shaft and load carried by tip resistance. An extensive subsurface investigations program is performed at the project site to properly characterize the properties of the different ground layers. Using the pile load tests results, the ultimate pile capacities are computed using both Chin and Decourt methods. The analysis of the instrumented load tests shows that no load is transferred to the pile tip. Thus, only side shaft resistance is mobilized during loading. The shaft side resistance is computed for all the load tests using the load–displacement measurements. The back-calculated capacities are compared with values obtained using a plethora of empirical correlations to identify the most suitable for use in Dubai limestone. The empirically computed shaft capacities exhibit a large degree of variability. A site-specific correlation is deduced using the available data.