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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. [ABSTRACT FROM AUTHOR]

Gravity installed plate anchor (GIPLA) is made mainly of steel plates. It features a swivel mooring arm located close to the anchor tip. Its more complex geometry inevitably complicates the prediction of its keying behavior, hence its capacity. This paper investigated the development of GIPLA׳s movements during its keying and its pullout capacity in NC clay. A plasticity model of yield envelops was constructed and used to predict anchor keying behaviors and its capacities. The plasticity model was validated by 3D large deformation finite element analysis based on remeshing and interpolation technique with small strain model. A parametric study on the keying and capacity development of a deeply embedded GIPLA in NC clay was performed by the plasticity model due to its simplicity and efficiency. The effects of anchor loading angle, anchor padeye eccentricity and soil strength profile were investigated. To encourage anchor “diving” behavior after keying and to keep anchor capacity reasonably high, it was recommended that the anchor loading angle to the horizontal at mudline should be 30° or less and the anchor padeye offset angle be in the range of 15°~25°. The soil non-homogeneity due to the linearly varying strength profile also affect anchor keying trajectory. [ABSTRACT FROM AUTHOR]