Lateral behaviour of composite tapered piles in dense sand

When used in harsh environments and offshore applications, conventional pile materials (such as steel, timber and concrete) are prone to costly durability problems, such as corrosion in reinforced/prestressed concrete and steel shell piles. Fibreglass-reinforced polymer (FRP) composites provide a corrosion-resistant construction material. FRP-concrete composite piles have been used successfully over the last decade in several projects for fendering applications. This paper investigates the behaviour under lateral loading of FRP composite tapered and cylindrical piles filled with self-consolidating concrete (SCC) and driven in dense sand enclosed in a pressure chamber. Seventeen pile installations were conducted using toe driving and conventional head driving. The piles were subsequently subjected to static lateral load tests. The results show that the pile taper increased its lateral capacity and enhanced its overall performance. A taper coefficient, K-tl, was introduced to account for the taper effect on the lateral response of piles. The experimental results were compared with two commonly used approaches for the analysis of the lateral response of piles: the p-y curves approach and the strain wedge model (SWM). The taper coefficient can be easily incorporated in both methods to account for the effect of pile taper. The comparison between the measured and computed responses showed. that both the p-y curve approach and the SWM, modified using K-tl, can be used for the prediction of the lateral response of tapered piles.