Laboratory experiments of ice scour processes: rigid ice indentor

A laboratory program has been carried out to measure the loads and seabed response due to an ice block scouring a seabed. Fourteen tests (35 configurations) were performed with a variety of seabed types that are representative of the oil discovery areas within the Jeanne dʹArc Basin area of the northeastern Grand Banks. The tests showed that the scour profiles were generally very uniform along each section of the test channels. The ice did not fail in shear, but general erosion was observed. Scour depths measured in post test were smallest for scouring through a gravel seabed. Regression analysis yielded the following empirical relationships for the loads:P=−1.8v+10.3h+2.3B−0.8 for the gravel bed (r2=0.93)P=8.5v+46.3h+28.5B−7.6 for the sand bed (r2=0.90)P=53.4v+45.8h+13.5B−11.3 for the sand/gravel bed (r2=0.96)P=13.2v+33.4h+11.6B−0.6S−2.4 for all seabeds (r2=0.74)where v is velocity in metres/second; h is scour depth in metres; B is ice block width, also in metres; and S is the seabed type, represented by the D50 value of the seabed material.