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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ftdoajarticles:oai:doaj.org/article:e57ced0cfe3a4ece9e60b26e15a7cd33 2023-05-15T14:51:11+02:00 Geometric and Material Variability Influences Stress States Relevant to Coastal Permafrost Bluff Failure Matthew A. Thomas Alejandro Mota Benjamin M. Jones R. Charles Choens Jennifer M. Frederick Diana L. Bull 2020-05-01T00:00:00Z https://doi.org/10.3389/feart.2020.00143 https://doaj.org/article/e57ced0cfe3a4ece9e60b26e15a7cd33 EN eng Frontiers Media S.A. https://www.frontiersin.org/article/10.3389/feart.2020.00143/full https://doaj.org/toc/2296-6463 2296-6463 doi:10.3389/feart.2020.00143 https://doaj.org/article/e57ced0cfe3a4ece9e60b26e15a7cd33 Frontiers in Earth Science, Vol 8 (2020) Arctic Alaska coastal erosion permafrost bluff failure numerical modeling mechanics Science Q article 2020 ftdoajarticles https://doi.org/10.3389/feart.2020.00143 2022-12-31T01:47:27Z 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. Article in Journal/Newspaper Arctic Ice permafrost wedge* Alaska Directory of Open Access Journals: DOAJ Articles Arctic The Bluff ENVELOPE(-61.567,-61.567,-64.367,-64.367) Frontiers in Earth Science 8 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Arctic Alaska coastal erosion permafrost bluff failure numerical modeling mechanics Science Q |
spellingShingle |
Arctic Alaska coastal erosion permafrost bluff failure numerical modeling mechanics Science Q Matthew A. Thomas Alejandro Mota Benjamin M. Jones R. Charles Choens Jennifer M. Frederick Diana L. Bull Geometric and Material Variability Influences Stress States Relevant to Coastal Permafrost Bluff Failure |
topic_facet |
Arctic Alaska coastal erosion permafrost bluff failure numerical modeling mechanics Science Q |
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. |
format |
Article in Journal/Newspaper |
author |
Matthew A. Thomas Alejandro Mota Benjamin M. Jones R. Charles Choens Jennifer M. Frederick Diana L. Bull |
author_facet |
Matthew A. Thomas Alejandro Mota Benjamin M. Jones R. Charles Choens Jennifer M. Frederick Diana L. Bull |
author_sort |
Matthew A. Thomas |
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 |
publisher |
Frontiers Media S.A. |
publishDate |
2020 |
url |
https://doi.org/10.3389/feart.2020.00143 https://doaj.org/article/e57ced0cfe3a4ece9e60b26e15a7cd33 |
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_source |
Frontiers in Earth Science, Vol 8 (2020) |
op_relation |
https://www.frontiersin.org/article/10.3389/feart.2020.00143/full https://doaj.org/toc/2296-6463 2296-6463 doi:10.3389/feart.2020.00143 https://doaj.org/article/e57ced0cfe3a4ece9e60b26e15a7cd33 |
op_doi |
https://doi.org/10.3389/feart.2020.00143 |
container_title |
Frontiers in Earth Science |
container_volume |
8 |
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1766322244057825280 |