The seismic performance of port structures has been well documented following
recent earthquakes, and indicates that port structures are highly susceptible to earthquake-induced
damages. These damages are primarily due to soil liquefaction and the associated
ground failures. Sheet pile bulkheads provide vital intermodal and lifeline transportation
links between water-side and land-side traffic, and are waterfront structures particularly
vulnerable to liquefaction-induced damages. Due to the prevalence of liquefaction-induced
damages, many ports are utilizing soil improvement techniques to mitigate these
hazards.
Many port authorities have proposed utilizing performance-based design criteria to
limit potential earthquake-induced damages. The current design method for sheet pile
walls (Mononobe-Okabe) is based on simple, limit equilibrium analysis techniques,
which are poorly suited for performance-based design. Recent advancements in the
seismic design of sheet pile walls have addressed some of the limitations of the current
design methods, but are still inadequate for performing a complete, performance-based design for locations that contain potentially liquefiable soils and/or where soil
improvement strategies have been instituted.
This study has focused on conducting an empirical investigation and numerical
modeling to determine the seismic performance of sheet pile walls, and the performancebased
benefit of soil improvement through densification. A case history validated,
nonlinear effective stress computer program was used to perform numerical parametric
studies on various design parameters (earthquake properties, depth of sheet pile
embedment, sheet pile wall stiffness, tie rod length, density of the backfill, and extent of
soil densification). The results have been presented as a performance-based design
method, and include a design chart that provides practitioners with a preliminary design
tool that may be used to estimate the seismic deformations of sheet pile walls with or
without soil improvement.
The study has demonstrated that soil densification can greatly reduce the seismicallyinduced
deformations, especially when the magnitude of soil improvement extends
beyond the location of the anchor. The study has also demonstrated that the use of soil
densification techniques for mitigating seismic hazards may not be adequate in limiting
deformations to allowable limits, and that other methods of soil improvement
(cementation, drainage, etc.) or structural improvements may also be required. / Graduation date: 1998
| Identifer | oai:union.ndltd.org:ORGSU/oai:ir.library.oregonstate.edu:1957/33918 |
| Date | 23 February 1998 |
| Creators | McCullough, Nason J. |
| Contributors | Dickenson, Stephen E. |
| Source Sets | Oregon State University |
| Language | en_US |
| Detected Language | English |
| Type | Thesis/Dissertation |
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