P-y models: Data

P-y models are used to specify horizontal soil loads for near-vertical lines that extend beneath the seabed.

You can define one or more named P-y models which can then be associated with individual lines. The P-y model data can be defined as varying with depth beneath the seabed.

Input data for P-y models

Name

Used to refer to the P-y model.

Depth below seabed

The range of depths over which each set of P-y curve data applies. The P-y curve data are treated as constant over this range of depths. However, the two API RP 2A formulations provide load-deflection curves that vary with depth given constant input data.

Model type

One of the following:

API RP 2A soft clay, which uses the load-deflection curves for piles in soft clay under short-term static loading, as specified in API RP 2A (2000).
API RP 2A sand, which (similarly) uses the API RP 2A (2000) load-deflection curves for sand.
P-y table, allowing you to define the load-deflection curves directly in tabular form.

Effective unit soil density (soft clay and sand)

The effective density of the soil, equal to the saturated soil density minus the sea water density.

Note:

The value specified in OrcaFlex is a density (mass per unit volume), whereas in the API RP 2A code the value is expressed as a weight (force per unit volume).

Undrained shear strength, J, ε_c (soft clay)

The input parameters to the API RP 2A soft clay model. Note that ε_c is specified as a percentage strain.

C1, C2, C3, k (sand)

The input parameters to the API RP 2A sand model.

Deflection, resistance (table)

The load-deflection curve in tabulated form.