Conventional simplified analysis methods for seismic design of gravity-type quay wall are based on providing capacity to resist a design seismic force, but they do not provide information on the performance of a structure when the limit of the force-balance is exceeded. In order to overcome the limitation of conventional seismic design methods, a performance-based seismic coefficient (khk) concept which can verify the performance of port structures exceeding the limit of force-balance was proposed in the technical standards and commentaries for port and harbour facilities in Japan, published in 2007. The khk concept considers the deformation of the quay wall, the wall height, the effect of frequency characteristics and duration of the ground motions, and the natural period of the ground. This paper proposes a performance verification method for the gravity-type quay wall during earthquakes through dynamic centrifuge model tests. The centrifuge tests were used in the present study to validate the proposed khk concept for evaluating the seismic performance of the quay wall under various conditions. The reliability of the khk concept was evaluated for different wall heights, earthquake motions and the thickness of subsoil, which are the primary variables in the khk equation. In addition, some improvements that should be considered in the future revision of the khk equation are discussed in this research.
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