Full-Scale Test and Numerical Simulation of a Truck Impacting a Group of Side-by-Side Piles

Abstract

This paper describes a study of the behavior of a group of piles under impact loading. Many structures such as bridge piers, offshore platforms, or berthing foundations can be subjected to the horizontal impacts from ships during their lifetime in which the system failure would have serious consequences. Guardrails for road side safety are another type of impact-resisting system that are extensively used and have a direct relation to human life and cost. Moreover groups of piles can serve as an efficient and relatively cost-effective protective structure around critical and important facilities. Prediction of the system response during the impact can lead to a more effective and economical design. There has been a very limited amount of experimental work on lateral response of group piles under impact loading in particular in the field of full-scale tests. This paper describes a full-scale field test performed on a group of eight side-by-side piles embedded 3 m in a loose sand to sustain an impact of a 6800 kg truck with an approaching velocity of 80 km/h. The instrumentation includes accelerometers on the truck, strain gauges on the posts, and high-speed cameras to capture the deflection. The eight posts and the connector beam have been simulated using an advanced numerical simulation software LS-DYNA (Livermore Software Technology Corporation) to characterize the features of the soil-pile-beam interaction under impact and improve the design methodology.