학술논문

Interpretation of a progressive slope movement using balanced cross sections and numerical integration
Document Type
Academic Journal
Source
Environmental & Engineering Geoscience. 14(2):121-131
Subject
30|Engineering geology
16|Structural geology
Allegan County Michigan
coastal environment
deformation
displacements
engineering properties
failures
faults
Gaussian quadrature
geometry
Great Lakes
kinematics
Lake Michigan
layered materials
Miami Park South Michigan
Michigan
Michigan Lower Peninsula
models
North America
numerical analysis
numerical models
slope stability
stratigraphic units
three-dimensional models
United States
Language
English
ISSN
1078-7275
Abstract
Gaussian quadrature, a numerical integration technique through fixed points, is applied to improve accuracy and efficiency in the cross-section balance modeling of a slope subjected to progressive displacements. This integration is employed to compute geometrical areas of individual stratigraphic units that have participated in the deformation. Given the initial and final states of a natural slope in which progressive failure has been carefully monitored for 7 years, the internal geometry of four stratigraphic layers that were displaced in a manner that characterizes the displacement kinematics of the entire slope has been analyzed. The area differences between the initial and final sections for three of the layers are zero. A fourth, basal, layer shows a unit area reduction of 13 percent, which can be accounted for by toe erosion. This implies that the total internal geometric area is found to be preserved during the course of the progressive deformation, a fact that is evident in repeated ground surveys conducted during the 7-year history of displacement. Also, factors of safety computed for the basal surface of slip at the initial and final stages of displacement monitoring demonstrate that the slope became less stable over a period of 7 years as a result of the progressive failure. Such a reduction in stability would be difficult to quantify without the application of numerical integration that allows the accurate construction of area-balanced geometrical models in a digital format amenable to validation and stability analysis.