The success of civil engineering construction in cold regions often depends on the
assessment of the potential for frost heave. Over the past two decades two models have
been presented to the engineering community to identify the frost heave potential,
namely: (1) the segregation potential (SP), and (2) the discrete ice lens (DIL) models.
These models are based on ice segregation parameters which can be obtained from simple
laboratory freezing tests. However, the reliability of the ice segregation parameters
obtained from the laboratory freezing tests is still in question.
In recognition of the need to improve the reliability of the measurement of ice
segregation parameters in a frost heave test, a study was conducted to: (1) investigate
several improvements in the step freezing test used to measure ice segregation
parameters, (2) examine several approximations used to interpret the laboratory step
freezing test results, (3) demonstrate the compatibility of the SP and DIL parameters, (4)
propose a method to obtain reliable ice segregation parameters, and (5) demonstrate the
applicability of the DIL model to address field frost heave problems.
The results of the study indicated: (1) the accuracy of measured ice segregation
parameters may be improved if step freezing tests are conducted under shallower
temperature gradients and the water intake velocity is accurately and continuously
monitored, (2) inappropriate approximations may produce a significant error in the
measurement of ice segregation parameters, (3) SP may be defined either by the ratios
of the (i) heave velocity/1.09 to the overall temperature gradient of the frozen soil, or
(ii) water intake velocity to the temperature gradient of the frozen fringe, (4) the SP and
DIL ice segregation parameters are compatible, and (5) the reliability of both models is
improved through the demonstration of the compatibility of the ice segregation
parameters.
The application of the frost heave prediction models was studied based on ice
segregation parameters determined with the improved laboratory procedure. A practical
method to predict the influence of the groundwater level using the DIL ice segregation
parameters was proposed. A probabilistic approach for the DIL frost heave model was
developed. / Graduation date: 1994
| Identifer | oai:union.ndltd.org:ORGSU/oai:ir.library.oregonstate.edu:1957/35611 |
| Date | 29 June 1993 |
| Creators | Ito, Yuzuru, 1958- |
| Contributors | Vinson, Ted S. |
| Source Sets | Oregon State University |
| Language | en_US |
| Detected Language | English |
| Type | Thesis/Dissertation |
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