Bounding surface model for soil resistance to planar cyclic lateral pile displacements

The development of an elastic-plastic bounding surface P-Y model for planar cyclic lateral pile motions is presented. The model includes damage mechanics and viscous components. The principal motivation behind the model development is to realistically capture the hysteretic energy damping associated with dynamic loading of subsea foundations exposed to environmentally induced loads. Responses from illustrative analyses of dynamic cyclic free vibration response of conductors supporting heavy wellhead equipment indicate that the model produces hysteretic soil damping consistent with expected values. The model can be calibrated to reproduce results obtained from traditional P-Y models under monotonic loading conditions for cohesive soils.