Sensitivity analysis of the seismic response of gravity quay walls to perturbations of input parameters

• A particular typology of gravity quay wall is studied.
• Advanced numerical analyses are performed to assess its seismic performance.
• Tornado (or Swing) and First Order Second Moment (FOSM) analyses are implemented.
• Results from both approaches are compared.

Gravity quay walls are extremely common geotechnical systems in many ports. In earthquake-prone regions it is important to assess the seismic behavior of such berths, and to determine which input parameters have the largest effect on the response. This study presents a seismic sensitivity analysis of a blockwork wharf, wherein the effects of inherent variations of ground motions and geotechnical quantities are investigated. An advanced finite difference model is used to propagate the uncertainties, and several nonlinear dynamic analyses are performed for this purpose. Two methodologies are also adopted: Tornado and First Order Second Moment (FOSM). Results from both approaches are found to be in fair agreement, and throw light on the relative importance of input parameters for the considered case. It is showed that the uncertainties associated with the seismic input, i.e. intensity level and ground motion definition, are the most relevant ones. Then there are the effects of the geotechnical parameters, the largest of which is given by the friction angle of the backfill.