MICHAEL RIEMER
Associate Adjunct Professor
432 Davis Hall
Phone: (510) 642-7457
FAX: (510) 642-7476
riemer@ce.berkeley.edu
Education
- B.S., Civil Engineering, Virginia Tech, 1986
- M.S., Geotechnical Engineering, U.C. Berkeley, 1987
- PhD., Geotechnical Engineering, U.C. Berkeley, 1992
Teaching and Research
Prof. Riemer teaches the undergraduate course in Geotechnical
Engineering Design (CE177) and the graduate level Advanced Soil
Mechanics Laboratory (CE270L), as well as working directly with
students at all levels with independent experimental research in the
geotechnical laboratories. His research interests are centered on the
evaluation of soil properties both in the laboratory and in-situ, and
the prediction of soil response to static and dynamic loading of
different types.
He is currently involved in evaluating the development of porewater
pressures in saturated soils during seismic loading, and the effects
of these pore pressures on other engineering properties, including the
assessment and modeling of liquefaction flow failures.
Effects of Loading Frequency on the Liquefaction Behavior of Clean
Sands (with Prof.
Jonathan Bray)
Earthquakes in different geologic domains can exhibit distinct
characteristics of the ground motions, including predominant
frequencies that can vary by an order of magnitude. Since the exact
nature of the interactions between acceleration, soil strain, and pore
pressure generation during liquefaction are not well understood, this
experimental program was undertaken to evaluate the effects of the
frequency of loading on the liquefaction response of clean sands.
Liquefaction Remediation for Existing Bridge Foundations
Due to their embedment in typically loose alluvial soils, the
abutments of bridges are often susceptible to large deformations
during and after seismic loading. Such deformations can induce
failures of the bridges, often causing substantial disruptions in the
movements of emergency vehicles and supplies at a time of critical
need. This research focuses on evaluating the liquefaction
susceptibility of bridge foundations, and the resulting movements. By
comparing the stability of various treatment options using numerical
analyses, the project will produce guidelines for identifying the most
efficient means of stabilizing such structures through the effective
application of soil improvement techniques.
Collapse of Saturated Soil Due to a Reduction in Confinement (with
Dr. Scott Anderson)
This research is focused on evaluating the conditions under which
hillside deposits can be destabilized by the infiltration of water and
the resulting decline in effective confining stress. Evidence of flow
failures resulting from such behavior can be observed in the field,
but the identification of deposits susceptible to this failure mode
requires an understanding of the collapse mechanism, and its
dependence on the soil's stress path in (p'-q-e) space. Current work
involves the delineation and modeling of the collapse surface for both
a standard sand and for a clayey silt known to produce such flow
failures in its native state.
Effects of Aging on the Liquefaction Susceptibility of Sands in the
Northridge Earthquake
The currently adopted methods for evaluating liquefaction
susceptibility using field measurements are based largely on an
empirical database of soil deposits that have experienced seismic
loading and either have or have not liquefied as a result. Nearly all
of these deposits are relatively young (Holocene aged). The limited
data available on older deposits (including Miocene deposits
previously tested at U.C. Berkeley) suggest that appreciable
resistance to liquefaction can be developed over time that are not
captured by the current field methods. This research will include
testing of undisturbed sand samples from various locations affected by
the Northridge Earthquake to assess their liquefaction resistance and
compare it with those values estimated by conventional field methods.