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Title: Geotechnical Engineering in the Face of Climate Change: Role of Multi-Physics Processes in Partially Saturated Soils
Climate change is expected to alter the statistics of extreme events including rainfall storms, floods, droughts, and heatwaves. Climate-adaptive geotechnical structures warrant a quantitative assessment of the impacts of emerging and projected extreme patterns on the short and long-term behaviors of earthen structures. Furthermore, long-term changes to soil carbon and moisture due to non-extreme climate events should also be considered. While several large-scale studies have been conducted to evaluate various aspects of climate change, there is a clear gap in the state of knowledge in terms of assessing the resilience of geotechnical structures to changes in climatic trends (e.g., warmer climate, protracted droughts, intensified extreme precipitations, and sea level rise). The majority of the aforementioned climatic trends pose multi-physics problems involving thermo-hydro-mechanical (THM) processes in partially saturated soils and earthen structures. This review paper discusses how soil-atmospheric interactions and extreme event patterns in a changing climate can alter soil properties and loading conditions, affecting the performance of partially saturated geotechnical structures. We speculate how changes in climatic trends may weaken partially saturated earthen structures through strength reduction, drying, soil desiccation cracking, shrinkage, microbial oxidation of soil organic matter, fluctuation in the ground water table, land and surface erosion, and highly more » dynamic pore pressure changes. Each of these weakening processes is primarily induced by variations in the soil moisture and temperature. Finally, we discuss potential modes of failure imposed on partially saturated earthen structures by climatic trends. « less
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Award ID(s):
1634748 1635797
Publication Date:
Journal Name:
Proc. 2018 International Foundations Congress and Equipment Exposition, IFCEE 2018: Advances in Geomaterial Modeling and Site Characterization, Geotechnical Special Publication No. 295
Page Range or eLocation-ID:
353 to 364
Sponsoring Org:
National Science Foundation
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