Liquefaction analysis of a model anchored bulkhead in centrifuge

• Published in: Soil dynamics and earthquake engineering (1984) 1995, Vol.14 (5), p.347-360
• Main Authors: Bouckovalas, George, Ting, Nai-Hsin, Whitman, Robert V.
• Format: Article
• Language: English
• Subjects: bulkheads; Earth sciences; Earth, ocean, space; Earthquakes, seismology; Engineering and environment geology. Geothermics; Engineering geology; Exact sciences and technology; Internal geophysics; sand; seismic
• ISSN: 0267-7261; 1879-341X
• DOI: 10.1016/0267-7261(94)00042-F

The seismic response of anchored bulkheads with saturated backfill has been simulated in a series of centrifuge tests involving various intensities of shaking, two relative densities of the backfill and two pore fluids with different viscosities. The time history of input accelerations, excess pore pressures and displacements during each test were continuously recorded at several points in the backfill and on the bulkhead. In the following, these data are used to evaluate the accuracy of a numerical method developed for simplified computations of earthquake-induced excess pore pressures and permanent displacements in saturated soils. Two sets of predictions are evaluated: Stage I predictions, based solely upon an initial evaluation of the input parameters and no feedback from the results of the centrifuge tests, and Stage II predictions, based on revised values of input parameters estimated from back-analysis of the centrifuge test results. Stage I predictions are in good agreement with measurements of excess pore pressures and outward wall displacements in the tests with a high viscosity, glycerol solution as pore fluid. For tests with water as pore fluid, good predictions are obtained with Stage II predictions when the stiffness of the anchor is reduced by about 15%, and the permeability coefficient during shaking is reduced to one quarter of the value measured in falling head permeability tests.