Keying behavior of suction embedded plate anchors with flap in clay

Abstract

Suction embedded plate anchors (SEPLAs) have been applied extensively in deepwater projects due to their high efficiency and low cost. In this paper, a new plasticity model was developed to simulate the keying behavior of SEPLAs. The model was based on three groups of yield envelopes, which considered three different states between the flap and the main plate. Thus, the plasticity model can consider the flap rotation relative to the fluke. The anchor shank was also considered to investigate the three dimensional (3D) effects of the actual SEPLA shape when deriving the yield envelops. A three dimensional large deformation finite element (3D-LDFE) model with flap rotation and shank considered was also set up. Then 3D-LDFE analysis was carried out to verify the plasticity model. The results given by 3D-LDFE analyses agree well with those by plasticity analyses. The effects of the flap on the embedment loss and pullout capacity, and the effects of loading eccentricity and pullout angle on diving behavior are investigated. Optimal padeye offset and pullout angle to drive the anchor diving are proposed.