Experimental study on the distribution law of the blade foot resistance of a large deep-water open caisson in sand

Abstract

Research on the sinking of large deep-water open caissons in sand via field monitoring, centrifugal model testing and 1 g simulation testing shows that the distribution law of the blade foot resistance is related to the caisson burial depth, mud surface height inside the blade foot and sinking state, and stress concentrates near rectangular caisson corners. When the height of the mud surface inside the blade foot does not exceed the top of the slope, the stress of the tread in the noncorner area increases linearly with the mud surface height and with the burial depth of the caisson. The slope stress exhibits a cubic distribution, and the ratio of the average slope stress to tread stress is a constant 0.28. When the height of the mud surface inside the blade foot exceeds the top of the slope, the slope stress maintains a cubic distribution, and the slope stress near the foot surface of the blade increases more obviously. Based on the cross-validation of different tests, a method for calculating the blade foot resistance of a large deep-water caisson is proposed, and the application scope is explored by centrifugal model tests and deep soil load tests.