Geometric and Material Variability Influences Stress States Relevant to Coastal Permafrost Bluff Failure
Scientific knowledge and engineering tools for predicting coastal erosion are largely confined to temperate climate zones that are dominated by non-cohesive sediments. The pattern of erosion exhibited by the ice-bonded permafrost bluffs in Arctic Alaska, however, is not well-explained by these tools...
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ftosti:oai:osti.gov:1770781 2023-07-30T04:01:16+02:00 Geometric and Material Variability Influences Stress States Relevant to Coastal Permafrost Bluff Failure Thomas, Matthew A. Mota, Alejandro Jones, Benjamin M. Choens, R. Charles Frederick, Jennifer M. Bull, Diana L. 2022-11-11 application/pdf http://www.osti.gov/servlets/purl/1770781 https://www.osti.gov/biblio/1770781 https://doi.org/10.3389/feart.2020.00143 unknown http://www.osti.gov/servlets/purl/1770781 https://www.osti.gov/biblio/1770781 https://doi.org/10.3389/feart.2020.00143 doi:10.3389/feart.2020.00143 54 ENVIRONMENTAL SCIENCES 2022 ftosti https://doi.org/10.3389/feart.2020.00143 2023-07-11T10:01:56Z Scientific knowledge and engineering tools for predicting coastal erosion are largely confined to temperate climate zones that are dominated by non-cohesive sediments. The pattern of erosion exhibited by the ice-bonded permafrost bluffs in Arctic Alaska, however, is not well-explained by these tools. Investigation of the oceanographic, thermal, and mechanical processes that are relevant to permafrost bluff failure along Arctic coastlines is needed. We conducted physics-based numerical simulations of mechanical response that focus on the impact of geometric and material variability on permafrost bluff stress states for a coastal setting in Arctic Alaska that is prone to toppling mode block failure. Our three-dimensional geomechanical boundary-value problems output static realizations of compressive and tensile stresses. We use these results to quantify variability in the loci of potential instability. We observe that niche dimension affects the location and magnitude of the simulated maximum tensile stress more strongly than the bluff height, ice wedge polygon size, ice wedge geometry, bulk density, Young's Modulus, and Poisson's Ratio. Our simulations indicate that variations in niche dimension can produce radically different potential failure areas and that even relatively shallow vertical cracks can concentrate displacement within ice-bonded permafrost bluffs. These findings suggest that stability assessment approaches, for which the geometry of the failure plane is delineated a priori, may not be ideal for coastlines similar to our study area and could hamper predictions of erosion rates and nearshore sediment/biogeochemical loading. Other/Unknown Material Arctic Ice permafrost wedge* Alaska SciTec Connect (Office of Scientific and Technical Information - OSTI, U.S. Department of Energy) Arctic The Bluff ENVELOPE(-61.567,-61.567,-64.367,-64.367) Frontiers in Earth Science 8 |
institution |
Open Polar |
collection |
SciTec Connect (Office of Scientific and Technical Information - OSTI, U.S. Department of Energy) |
op_collection_id |
ftosti |
language |
unknown |
topic |
54 ENVIRONMENTAL SCIENCES |
spellingShingle |
54 ENVIRONMENTAL SCIENCES Thomas, Matthew A. Mota, Alejandro Jones, Benjamin M. Choens, R. Charles Frederick, Jennifer M. Bull, Diana L. Geometric and Material Variability Influences Stress States Relevant to Coastal Permafrost Bluff Failure |
topic_facet |
54 ENVIRONMENTAL SCIENCES |
description |
Scientific knowledge and engineering tools for predicting coastal erosion are largely confined to temperate climate zones that are dominated by non-cohesive sediments. The pattern of erosion exhibited by the ice-bonded permafrost bluffs in Arctic Alaska, however, is not well-explained by these tools. Investigation of the oceanographic, thermal, and mechanical processes that are relevant to permafrost bluff failure along Arctic coastlines is needed. We conducted physics-based numerical simulations of mechanical response that focus on the impact of geometric and material variability on permafrost bluff stress states for a coastal setting in Arctic Alaska that is prone to toppling mode block failure. Our three-dimensional geomechanical boundary-value problems output static realizations of compressive and tensile stresses. We use these results to quantify variability in the loci of potential instability. We observe that niche dimension affects the location and magnitude of the simulated maximum tensile stress more strongly than the bluff height, ice wedge polygon size, ice wedge geometry, bulk density, Young's Modulus, and Poisson's Ratio. Our simulations indicate that variations in niche dimension can produce radically different potential failure areas and that even relatively shallow vertical cracks can concentrate displacement within ice-bonded permafrost bluffs. These findings suggest that stability assessment approaches, for which the geometry of the failure plane is delineated a priori, may not be ideal for coastlines similar to our study area and could hamper predictions of erosion rates and nearshore sediment/biogeochemical loading. |
author |
Thomas, Matthew A. Mota, Alejandro Jones, Benjamin M. Choens, R. Charles Frederick, Jennifer M. Bull, Diana L. |
author_facet |
Thomas, Matthew A. Mota, Alejandro Jones, Benjamin M. Choens, R. Charles Frederick, Jennifer M. Bull, Diana L. |
author_sort |
Thomas, Matthew A. |
title |
Geometric and Material Variability Influences Stress States Relevant to Coastal Permafrost Bluff Failure |
title_short |
Geometric and Material Variability Influences Stress States Relevant to Coastal Permafrost Bluff Failure |
title_full |
Geometric and Material Variability Influences Stress States Relevant to Coastal Permafrost Bluff Failure |
title_fullStr |
Geometric and Material Variability Influences Stress States Relevant to Coastal Permafrost Bluff Failure |
title_full_unstemmed |
Geometric and Material Variability Influences Stress States Relevant to Coastal Permafrost Bluff Failure |
title_sort |
geometric and material variability influences stress states relevant to coastal permafrost bluff failure |
publishDate |
2022 |
url |
http://www.osti.gov/servlets/purl/1770781 https://www.osti.gov/biblio/1770781 https://doi.org/10.3389/feart.2020.00143 |
long_lat |
ENVELOPE(-61.567,-61.567,-64.367,-64.367) |
geographic |
Arctic The Bluff |
geographic_facet |
Arctic The Bluff |
genre |
Arctic Ice permafrost wedge* Alaska |
genre_facet |
Arctic Ice permafrost wedge* Alaska |
op_relation |
http://www.osti.gov/servlets/purl/1770781 https://www.osti.gov/biblio/1770781 https://doi.org/10.3389/feart.2020.00143 doi:10.3389/feart.2020.00143 |
op_doi |
https://doi.org/10.3389/feart.2020.00143 |
container_title |
Frontiers in Earth Science |
container_volume |
8 |
_version_ |
1772812015961636864 |