PULL-OUT CAPACITY ANALYSES OF SUCTION ANCHORS FOR TENSION LEG PLATFORMS

Tension leg platforms (TLP) may be tethered to suction anchors (foundations with skirts) penetrated into the seabed beneath each corner of the platform. This solution was chosen by Saga Petroleum a.s. on the Snorre Field in the North Sea, and similar solutions are considered elsewhere. The anchors will be subjected to a combination of static tension and cyclic loads during storms. The pull-out capacity of the anchors under this loading is crucial for the successful operation of the platform. The method for establishing a cyclic shear strength from laboratory test results and how the calculations are performed are shown. The calculation procedure is verified by comparing predicted and measured pull-out capacities of four field model tests of anchors in soft clay.