Static lateral pile analysis in Dubai sedimentary rock

Analysis and calculation of lateral pile load capacities using appropriate methods is a challenging task for geotechnical engineers. Majorly, piles in Dubai are rock fully socketed with top strata medium dense to dense silty sand or sedimentary rock resisting lateral loads. In the current study, two field piles lateral load test results were chosen for examining different methods used by local geotechnical engineers, where ground lithology constitutes fragile sandstone upto similar to 8 m below ground level overlying extremely weak conglomerate/siltstone. Assessing the efficacy of design parameters and analysis methodology is a pivotal aspect in preliminary evaluation of lateral load capacity of piles. In this research, two commonly adopted approaches (p-y non-linear analysis using L-pile software and finite element analysis using Plaxis-3D) were assessed by comparing them with field test results to predict lateral load capacity precisely. Design parameters were based on borehole data and laboratory tests near the test location. Even though finite element analysis predicted better than p-y non-linear analysis, lateral load capacities were underestimated in both piles analysed, which was related to assessment of input parameters. In addition, finite element analysis was used to back-calculate elastic modulus of rock that yields lateral deflection of pile close to field test results.