Determining the Threshold Pressure of Clay-Cutting by a Mobile Jet for Coastal Construction

ABSTRACT Gu, L.; Ni, F.; Xu, L., and Li, Z., 2018. Determining the threshold pressure of clay-cutting by a mobile jet for coastal construction. Trailing suction hopper dredgers (THSD) are widely used in channel excavation and coastal construction projects. In such projects, clay is a common soil that is difficult for the drag head of THSDs to dredge. Jet-cutting using a mobile jet is often adopted to improve the efficiency of the drag head, since it can create grooves into the clay surface and reduce cutting forces for the drag head. The jet pressure is an important factor for jet-cutting, so it is necessary to accurately grasp the threshold pressure of clay-cutting by the mobile jet. In this paper, clay samples with three different strengths (undrained shear strength Su = 16 kPa, 35 kPa, and 51 kPa) were prepared, and clay-cutting experiments using a mobile jet were conducted. The effects of parameters such as the nozzle diameter, the moving speed, and the jet pressure on the cutting results were investi...