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Proceedings of the International Conference on
Advances and New Challenges in Earthquake
Engineering Research, Hong Kong Volume
PERFORMANCE-BASED DESIGN OF
GRAVITY RETAINING WALL IN SEISMIC AREAS
X. Zeng
Department of Civil Engineering, Case Western Reserve University
Cleveland, Ohio, USA
ABSTRACT
Failure of gravity retaining walls occurred many times in past earthquakes. Typical failure mechanism
was either an overturn or a large lateral deformation beyond repair. Traditional design approaches based
on conventional limit equilibrium-based methods would emphasize on adopting a factor of safety against
such failure. The goal was to design a structure that can resist forces generated by a seismic event.
However, the cost of satisfying such requirement can be very high, especially for high intensity
earthquake of rare occurrence.
Performance-based design is a new methodology that emerged in the 1990s. The objective of this method
is to avoid the limitations of conventional seismic design method. In a performance-based design method,
a gravity retaining wall would be allowed to have an acceptable level of deformation that depends on the
function of the structure. The critical element in this design method is to calculate the displacement of a
gravity wall under a design earthquake. This paper reviews the methods that have been developed for
calculating lateral, rotational, and coupled displacement of gravity retaining walls. It also discusses the
role of comprehensive numerical codes in a performance-based design when simple analytical methods
cannot produce satisfactory results. An example is used to illustrate the application of a performancebased
design method, which in general leads to a more economical design. However, in order to apply this
approach in the field with confidence, the time history of the design earthquake needs to be known.
INTRODUCTION
Many failures of gravity type of retaining walls have been reported in past earthquakes, for example,
Tsuchida (1991) and Inagaki et al (1996). Most of the failures were caused by a large displacement of the
structure in forms of lateral displacement, settlement, or rotation. For example, during the Kobe
earthquake in 1995, caisson type quay walls at Port Island and Rokko Island had lateral displacement up
to more than 5 meters, settlement up to more than 2 meters, and rotation of several degrees, Inagaki et al
(1996). This kind of displacement was far above the acceptable level of damage allowed for this type of
structure and was very expensive to repair.