Effect of a constrictor plate on behavior of a model steel pipe pile driven in dense sand

Abstract

This study investigates the effect of a constrictor plate on the drivability and load-carrying capacity of open-ended pipe piles via a series of model pile tests. The model pile had an outer diameter of 88.9 mm and was driven in a dense sand to a depth of 670 mm using an impact hammer. Soil plug lengths were measured using a laser distance meter for the entire process of the pile driving. The model pile further employed a double-wall system to separately measure the annulus resistance, soil plug resistance, and outer shaft resistance. Two tests with a constrictor plate located at 98.4 mm and 200 mm above the pile base and one test without a constrictor plate were performed. The piles with a constrictor plate required about 15–20% more pile driving energy than the pile without a constrictor plate. Results from static load tests showed that the piles with a constrictor plate were able to resist more axial loads than the pile without a constrictor plate by about 25–38%.