Pub Date : 2024-11-07DOI: 10.1016/j.coldregions.2024.104358
Hassan Abbas Khawaja , Samaneh Keshavarzi , Adeel Yousuf , Manaf Muhammed , Muhammad Shakeel Virk , Derek Harvey , Gelareh Momen
This study explores the intricate heat transfer dynamics and thermographic patterns during the phase change from supercooled liquid water to ice. Using high-resolution, high-speed infrared thermography, real-time temperature data were captured during the freezing process. The resulting temperature profiles reveal critical insights into the freezing dynamics, particularly highlighting the rapid phenomena of recalescence in supercooled conditions. Notably, this study represents the first time recalescence, a rapid and previously elusive phenomenon, captured and documented in the scientific literature. Additionally, a mathematical model is developed to describe the recalescence phase on macro scale. These findings have practical relevance for various industries, aiding in the design of more efficient anti−/de-icing technologies, refrigeration systems, weather prediction models, and cryopreservation techniques. The study also opens new avenues for further exploration in understanding phase transitions in supercooled water.
{"title":"Exploring heat transfer in freezing supercooled water droplet through high-speed infrared thermography","authors":"Hassan Abbas Khawaja , Samaneh Keshavarzi , Adeel Yousuf , Manaf Muhammed , Muhammad Shakeel Virk , Derek Harvey , Gelareh Momen","doi":"10.1016/j.coldregions.2024.104358","DOIUrl":"10.1016/j.coldregions.2024.104358","url":null,"abstract":"<div><div>This study explores the intricate heat transfer dynamics and thermographic patterns during the phase change from supercooled liquid water to ice. Using high-resolution, high-speed infrared thermography, real-time temperature data were captured during the freezing process. The resulting temperature profiles reveal critical insights into the freezing dynamics, particularly highlighting the rapid phenomena of recalescence in supercooled conditions. Notably, this study represents the first time recalescence, a rapid and previously elusive phenomenon, captured and documented in the scientific literature. Additionally, a mathematical model is developed to describe the recalescence phase on macro scale. These findings have practical relevance for various industries, aiding in the design of more efficient anti−/de-icing technologies, refrigeration systems, weather prediction models, and cryopreservation techniques. The study also opens new avenues for further exploration in understanding phase transitions in supercooled water.</div></div>","PeriodicalId":10522,"journal":{"name":"Cold Regions Science and Technology","volume":"229 ","pages":"Article 104358"},"PeriodicalIF":3.8,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142661635","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-03DOI: 10.1016/j.coldregions.2024.104357
Chunlei Xie , Yaqian Dong , Ze Zhang , Xianglong Li , Andrei Zhang , Doudou Jin
Construction of embankments in the permafrost region significantly changes the heat exchange conditions and hydrothermal transport processes between permafrost and the external environment, causing changes in the state of permafrost under the embankment, which in turn affects the long-term stability of embankment impacts. Considering more complex forest environment and higher technical standard for expressway than ordinary highway, the hydrothermal and deformation characteristics of the embankment are investigated through a full-scale field experimental embankment of the Genhe-Labdalin highway. Further, the study delves into the influence of changes in the active layer thickness, hydrothermal processes, and water above the frozen layer on embankment stability. The main conclusions are as follows: 1) The permafrost table, temperature, moisture and deformation of the embankment showed lateral heterogeneity, with the three-former showing a “concave shape” and the left side (sunny slope) being lower than the right side (shady slope). 2) The permafrost table appears to be unconnected (thawing interlayer), creating preferential flow, thaw zones and even through-thaw zones. 3) Accompanied by the freezing and thawing process of the embankment, the deformation of the pavement is less delayed. These findings will be helpful for better understanding the hydrothermal characteristics of embankments in different frozen ground regions, and for providing important technical guidance to ensure the safe operation of engineering projects.
{"title":"Hydro-thermal processes and deformation of highway embankment in the active layer in a high-latitude permafrost region of Inner Mongolia in Northeast China","authors":"Chunlei Xie , Yaqian Dong , Ze Zhang , Xianglong Li , Andrei Zhang , Doudou Jin","doi":"10.1016/j.coldregions.2024.104357","DOIUrl":"10.1016/j.coldregions.2024.104357","url":null,"abstract":"<div><div>Construction of embankments in the permafrost region significantly changes the heat exchange conditions and hydrothermal transport processes between permafrost and the external environment, causing changes in the state of permafrost under the embankment, which in turn affects the long-term stability of embankment impacts. Considering more complex forest environment and higher technical standard for expressway than ordinary highway, the hydrothermal and deformation characteristics of the embankment are investigated through a full-scale field experimental embankment of the Genhe-Labdalin highway. Further, the study delves into the influence of changes in the active layer thickness, hydrothermal processes, and water above the frozen layer on embankment stability. The main conclusions are as follows: 1) The permafrost table, temperature, moisture and deformation of the embankment showed lateral heterogeneity, with the three-former showing a “concave shape” and the left side (sunny slope) being lower than the right side (shady slope). 2) The permafrost table appears to be unconnected (thawing interlayer), creating preferential flow, thaw zones and even through-thaw zones. 3) Accompanied by the freezing and thawing process of the embankment, the deformation of the pavement is less delayed. These findings will be helpful for better understanding the hydrothermal characteristics of embankments in different frozen ground regions, and for providing important technical guidance to ensure the safe operation of engineering projects.</div></div>","PeriodicalId":10522,"journal":{"name":"Cold Regions Science and Technology","volume":"229 ","pages":"Article 104357"},"PeriodicalIF":3.8,"publicationDate":"2024-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142661633","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-03DOI: 10.1016/j.coldregions.2024.104356
Qimin Chen , Yong Liu , Yang Wang , Libin Su , Yonggang Cheng
Freeze-thaw cycles significantly affect slope stability in seasonally frozen regions, posing serious threats to the functionality and safety of infrastructure. This study developed a coupled thermo-hydro-mechanical (THM) model of frozen soils that accounts for water migration, water-ice phase change, groundwater recharge, frost heave and thaw settlement deformation. The accuracy and reliability of the model was verified based on soil column test results. The change of temperature, water content, and displacement of a soil slope during freeze-thaw process was investigated. The results show that the water-heat transfer and deformation mainly occur in the shallow soils of the slope with changes in air temperature. The temperature fluctuations at the shoulder and face of the slope are more pronounced than those at the toe and crest of the slope. Water migration from the unfrozen zone to the freezing front due to the temperature gradient results in an increase in water content in the frozen zone. The slope shoulder exhibits the largest temperature fluctuations, leading to increased water migration and greater deformation. The rising groundwater table increases the total water content at the slope toe and base, exacerbating the frost heave and thaw settlement deformation, and reasonable groundwater table control intervals are provided. This study elucidates the thermo-hydro-mechanical coupling process and deformation mechanism of seasonally frozen soil slopes, and summarizes the failure modes, which provides a reference for the stability assessment and disaster prevention of soil slopes in cold regions.
{"title":"Investigation of coupled thermo-hydro-mechanical processes on soil slopes in seasonally frozen regions","authors":"Qimin Chen , Yong Liu , Yang Wang , Libin Su , Yonggang Cheng","doi":"10.1016/j.coldregions.2024.104356","DOIUrl":"10.1016/j.coldregions.2024.104356","url":null,"abstract":"<div><div>Freeze-thaw cycles significantly affect slope stability in seasonally frozen regions, posing serious threats to the functionality and safety of infrastructure. This study developed a coupled thermo-hydro-mechanical (THM) model of frozen soils that accounts for water migration, water-ice phase change, groundwater recharge, frost heave and thaw settlement deformation. The accuracy and reliability of the model was verified based on soil column test results. The change of temperature, water content, and displacement of a soil slope during freeze-thaw process was investigated. The results show that the water-heat transfer and deformation mainly occur in the shallow soils of the slope with changes in air temperature. The temperature fluctuations at the shoulder and face of the slope are more pronounced than those at the toe and crest of the slope. Water migration from the unfrozen zone to the freezing front due to the temperature gradient results in an increase in water content in the frozen zone. The slope shoulder exhibits the largest temperature fluctuations, leading to increased water migration and greater deformation. The rising groundwater table increases the total water content at the slope toe and base, exacerbating the frost heave and thaw settlement deformation, and reasonable groundwater table control intervals are provided. This study elucidates the thermo-hydro-mechanical coupling process and deformation mechanism of seasonally frozen soil slopes, and summarizes the failure modes, which provides a reference for the stability assessment and disaster prevention of soil slopes in cold regions.</div></div>","PeriodicalId":10522,"journal":{"name":"Cold Regions Science and Technology","volume":"229 ","pages":"Article 104356"},"PeriodicalIF":3.8,"publicationDate":"2024-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142661552","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-28DOI: 10.1016/j.coldregions.2024.104354
Renwei Li , Mingyi Zhang , Wansheng Pei , Zhao Duan , Haitao Jin , Xin Li
Climate warming has caused frequent thaw settlement in the permafrost region of the Qinghai-Tibet Plateau (QTP), significantly threatening the ecological environment and infrastructure. This study assesses thaw settlement susceptibility using index and machine learning (ML) models and compares their accuracies. The settlement index (Is), risk zonation index (Ir), and geohazard index (Ia) models were selected to map thaw settlement susceptibility, and their results were combined to construct a comprehensive index (Ic) model using a majority vote criterion. Based on 12 conditioning factors related to topography, soil, vegetation, and climate, susceptibility studies using artificial neural network (ANN), K-nearest neighbor (KNN), support vector machine (SVM), and random forest (RF) models were conducted. The results indicate that although the Ic model improves the accuracies of the Is, Ir and Ia models, it remains limited, with 75.06% of thaw settlements occurring in low and moderate susceptibility areas. Conversely, the ML models demonstrated superior accuracy, with the RF model performing the best, which remained only 13.87% of thaw settlements in low to moderate susceptibility regions, effectively pinpointing the Qiangtang Plateau (QP) and Three Rivers Source (TRS) region as high susceptibility areas. Notably, the Budongquan-Beiluhe sections of the Qinghai-Tibet Highway (QTH) and Qinghai-Tibet Railway (QTR) were identified as potential high-risk regions for thaw settlement. These findings offer valuable insights for thaw settlement susceptibility evaluation and disaster risk management in the QTP.
{"title":"Comparative study of thaw settlement susceptibility mapping for the Qinghai-Tibet Plateau based on index and machine learning models","authors":"Renwei Li , Mingyi Zhang , Wansheng Pei , Zhao Duan , Haitao Jin , Xin Li","doi":"10.1016/j.coldregions.2024.104354","DOIUrl":"10.1016/j.coldregions.2024.104354","url":null,"abstract":"<div><div>Climate warming has caused frequent thaw settlement in the permafrost region of the Qinghai-Tibet Plateau (QTP), significantly threatening the ecological environment and infrastructure. This study assesses thaw settlement susceptibility using index and machine learning (ML) models and compares their accuracies. The settlement index (Is), risk zonation index (Ir), and geohazard index (Ia) models were selected to map thaw settlement susceptibility, and their results were combined to construct a comprehensive index (Ic) model using a majority vote criterion. Based on 12 conditioning factors related to topography, soil, vegetation, and climate, susceptibility studies using artificial neural network (ANN), K-nearest neighbor (KNN), support vector machine (SVM), and random forest (RF) models were conducted. The results indicate that although the Ic model improves the accuracies of the Is, Ir and Ia models, it remains limited, with 75.06% of thaw settlements occurring in low and moderate susceptibility areas. Conversely, the ML models demonstrated superior accuracy, with the RF model performing the best, which remained only 13.87% of thaw settlements in low to moderate susceptibility regions, effectively pinpointing the Qiangtang Plateau (QP) and Three Rivers Source (TRS) region as high susceptibility areas. Notably, the Budongquan-Beiluhe sections of the Qinghai-Tibet Highway (QTH) and Qinghai-Tibet Railway (QTR) were identified as potential high-risk regions for thaw settlement. These findings offer valuable insights for thaw settlement susceptibility evaluation and disaster risk management in the QTP.</div></div>","PeriodicalId":10522,"journal":{"name":"Cold Regions Science and Technology","volume":"229 ","pages":"Article 104354"},"PeriodicalIF":3.8,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142661553","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-28DOI: 10.1016/j.coldregions.2024.104353
Vegard Hornnes , Evgenii Salganik , Knut Vilhelm Høyland
Sea-ice properties, such as porosity and strength, can have significant spatial variability at small scales. Quantifying this variability may give better estimates of the ice properties and their interrelation. Additionally, correlating in situ ice strength measurements and ice properties, including porosity, may improve understanding of the factors influencing ice strength. This paper presents measurements of sea-ice properties and strength on first- and second-year sea ice during the GoNorth expedition to the Arctic Ocean in October 2022. In situ borehole indentation measurements were co-located with measurements of physical properties, and the meter-scale variability of the physical properties and strength was investigated. Bulk density values found from hydrostatic weighing were 911 ± 5 kg m−3 for first-year and 904 ± 5 kg m−3 for second-year ice, with significantly less uncertainty than density values from the mass/volume method or from freeboard/draft measurements. The second-year ice was relatively saline, with a mean bulk salinity of 3.1 ± 0.5, and the ice was desalinated in the upper and lower 0.2 m. The bulk gas fraction in the second-year ice was 2.5 ± 0.5 %, similar to the first-year ice gas fraction of 2.8 ± 0.5 %. Gas fractions up to 6.5 % were observed in the second-year ice without any obvious correlation with the brine fraction. The second-year ice had larger spatial variability in thickness, porosity, grain structure, and ice strength compared to the first-year ice. Variability in bulk density and gas fraction were similar for first- and second-year ice, as the larger variability was mostly seen below the upper 0.4 m of the second-year ice. The borehole strength was 26.0 ± 4.4 MPa for first-year and 41.0 ± 12.1 MPa for second-year ice. There were indications that the total microporosity at indentation depth was related to in situ borehole strength ( = 0.82), and that brine volume was the most influential parameter. The relative variability in the local microporosity in the second-year ice (0.43) was greater than the relative variability in borehole strength (0.27), while the opposite was true for the first-year ice (0.09 versus 0.17).
{"title":"Relationship of physical and mechanical properties of sea ice during the freeze-up season in Nansen Basin","authors":"Vegard Hornnes , Evgenii Salganik , Knut Vilhelm Høyland","doi":"10.1016/j.coldregions.2024.104353","DOIUrl":"10.1016/j.coldregions.2024.104353","url":null,"abstract":"<div><div>Sea-ice properties, such as porosity and strength, can have significant spatial variability at small scales. Quantifying this variability may give better estimates of the ice properties and their interrelation. Additionally, correlating in situ ice strength measurements and ice properties, including porosity, may improve understanding of the factors influencing ice strength. This paper presents measurements of sea-ice properties and strength on first- and second-year sea ice during the GoNorth expedition to the Arctic Ocean in October 2022. In situ borehole indentation measurements were co-located with measurements of physical properties, and the meter-scale variability of the physical properties and strength was investigated. Bulk density values found from hydrostatic weighing were 911 ± 5 kg m<sup>−3</sup> for first-year and 904 ± 5 kg m<sup>−3</sup> for second-year ice, with significantly less uncertainty than density values from the mass/volume method or from freeboard/draft measurements. The second-year ice was relatively saline, with a mean bulk salinity of 3.1 ± 0.5, and the ice was desalinated in the upper and lower 0.2 m. The bulk gas fraction in the second-year ice was 2.5 ± 0.5 %, similar to the first-year ice gas fraction of 2.8 ± 0.5 %. Gas fractions up to 6.5 % were observed in the second-year ice without any obvious correlation with the brine fraction. The second-year ice had larger spatial variability in thickness, porosity, grain structure, and ice strength compared to the first-year ice. Variability in bulk density and gas fraction were similar for first- and second-year ice, as the larger variability was mostly seen below the upper 0.4 m of the second-year ice. The borehole strength was 26.0 ± 4.4 MPa for first-year and 41.0 ± 12.1 MPa for second-year ice. There were indications that the total microporosity at indentation depth was related to in situ borehole strength (<span><math><msup><mi>R</mi><mn>2</mn></msup></math></span> = 0.82), and that brine volume was the most influential parameter. The relative variability in the local microporosity in the second-year ice (0.43) was greater than the relative variability in borehole strength (0.27), while the opposite was true for the first-year ice (0.09 versus 0.17).</div></div>","PeriodicalId":10522,"journal":{"name":"Cold Regions Science and Technology","volume":"229 ","pages":"Article 104353"},"PeriodicalIF":3.8,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142586072","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-28DOI: 10.1016/j.coldregions.2024.104352
Wenliang Qiu , Kuan Li , Xin Zhao , Zhaolong Hou , Zhenguo Wang , Junpeng Yu
Static ice pressure is an important factor threatening the structural safety of bridges built in cold region reservoirs. Bridge piers will be subjected to high static ice pressure during the conversion of water to ice, which may cause deformation or even failure of piers. To investigate the spatial and temporal distribution of static ice pressure, this study carried out a two-year field observation experiment on the ice sheet of the Xilamulun Reservoir in Inner Monggol, China. A novel ice pressure panel was designed to measure static ice pressure in this work. Meanwhile, the air temperature, ice temperature, and ice thickness were recorded to analyze the influencing factors of static ice pressure. The results show that the new ice pressure panel provided an accurate measurement of the varying ice pressure and its vertical distribution within the ice sheet. The ice thickness growth factor was calculated based on the Freezing Ice Degree Day model, and snowfall was the critical parameter affecting the ice thickness growth factor. The new formulas for calculating the temperature distribution within the ice sheet were presented, in which critical parameters were determined based on measured data. The calculated ice pressures matched well with the observed values, which indicates the validity of the presented formulas. The maximum ice pressure on piers occurred at 1/3 to 1/2 of the ice thickness below the ice surface and gradually moved downward as the ice thickness increased. Moreover, the ice pressure is not only affected by the air temperature but also by the cracking state of the ice sheet, constraints, sunshine time, etc. This study can be used to predict ice sheet growth, ice pressure, and ice temperature distribution and contribute to the ice-resistant design of bridge piers in cold region reservoirs.
{"title":"Prototype observation and analysis of static ice pressure on reservoir piers in cold regions","authors":"Wenliang Qiu , Kuan Li , Xin Zhao , Zhaolong Hou , Zhenguo Wang , Junpeng Yu","doi":"10.1016/j.coldregions.2024.104352","DOIUrl":"10.1016/j.coldregions.2024.104352","url":null,"abstract":"<div><div>Static ice pressure is an important factor threatening the structural safety of bridges built in cold region reservoirs. Bridge piers will be subjected to high static ice pressure during the conversion of water to ice, which may cause deformation or even failure of piers. To investigate the spatial and temporal distribution of static ice pressure, this study carried out a two-year field observation experiment on the ice sheet of the Xilamulun Reservoir in Inner Monggol, China. A novel ice pressure panel was designed to measure static ice pressure in this work. Meanwhile, the air temperature, ice temperature, and ice thickness were recorded to analyze the influencing factors of static ice pressure. The results show that the new ice pressure panel provided an accurate measurement of the varying ice pressure and its vertical distribution within the ice sheet. The ice thickness growth factor was calculated based on the Freezing Ice Degree Day model, and snowfall was the critical parameter affecting the ice thickness growth factor. The new formulas for calculating the temperature distribution within the ice sheet were presented, in which critical parameters were determined based on measured data. The calculated ice pressures matched well with the observed values, which indicates the validity of the presented formulas. The maximum ice pressure on piers occurred at 1/3 to 1/2 of the ice thickness below the ice surface and gradually moved downward as the ice thickness increased. Moreover, the ice pressure is not only affected by the air temperature but also by the cracking state of the ice sheet, constraints, sunshine time, etc. This study can be used to predict ice sheet growth, ice pressure, and ice temperature distribution and contribute to the ice-resistant design of bridge piers in cold region reservoirs.</div></div>","PeriodicalId":10522,"journal":{"name":"Cold Regions Science and Technology","volume":"229 ","pages":"Article 104352"},"PeriodicalIF":3.8,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142571540","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-22DOI: 10.1016/j.coldregions.2024.104342
Xusheng Wan , Hao Zhou , Fengxi Zhou , Jishuai Zhu , Khan Muhammad Shahab
The mechanical properties of frozen-concrete interfaces affect the stability and durability of engineering structures in cold regions. To investigate these properties, laboratory tests and numerical simulations were conducted to study the mesoscopic evolution of the shear stress-displacement relationship and the shearing process at the interface. The direct shear tests were performed at different environmental temperatures (−2 °C, −5 °C, and −10 °C) and normal stresses (100 kPa, 200 kPa, and 300 kPa) on the frozen soil-concrete interface, and Particle Flow Code (PFC) model of direct shear was developed. The mesoscopic parameters (particle displacement, rotation, force chain, stress, coordination number, porosity, fabric, etc.) of the interface during shearing were simulated using the PFC model. Moreover, the relationship among the interface temperature, cohesion, and friction coefficient was determined based on experimental data, and the accuracy of the PFC model was verified using previous experimental data. The results of the PFC shear model aligned well with those of the laboratory test, and the formation of shear bands was simulated well. The displacement of the soil particles on the upper layer outside the shear zone was uniform, and the direction was the same, whereas the particles inside the shear zone showed significant differences in the dislocation and rotation of the soil particles. The force chain, stress field, coordination number, and porosity were similar in the shear process and showed a concentrated distribution in the opposite direction of the shear motion, which reflected the consistency of the microcosmic response of the particles under the action of macroscopic external forces. The regression equations for the temperature, cohesion, and friction coefficient in this study can be used to simulate the shear behavior of frozen soil-concrete interfaces under different temperatures and normal stresses.
{"title":"Mesoscopic shear evolution characteristics of frozen soil-concrete interface","authors":"Xusheng Wan , Hao Zhou , Fengxi Zhou , Jishuai Zhu , Khan Muhammad Shahab","doi":"10.1016/j.coldregions.2024.104342","DOIUrl":"10.1016/j.coldregions.2024.104342","url":null,"abstract":"<div><div>The mechanical properties of frozen-concrete interfaces affect the stability and durability of engineering structures in cold regions. To investigate these properties, laboratory tests and numerical simulations were conducted to study the mesoscopic evolution of the shear stress-displacement relationship and the shearing process at the interface. The direct shear tests were performed at different environmental temperatures (−2 °C, −5 °C, and −10 °C) and normal stresses (100 kPa, 200 kPa, and 300 kPa) on the frozen soil-concrete interface, and Particle Flow Code (PFC) model of direct shear was developed. The mesoscopic parameters (particle displacement, rotation, force chain, stress, coordination number, porosity, fabric, etc.) of the interface during shearing were simulated using the PFC model. Moreover, the relationship among the interface temperature, cohesion, and friction coefficient was determined based on experimental data, and the accuracy of the PFC model was verified using previous experimental data. The results of the PFC shear model aligned well with those of the laboratory test, and the formation of shear bands was simulated well. The displacement of the soil particles on the upper layer outside the shear zone was uniform, and the direction was the same, whereas the particles inside the shear zone showed significant differences in the dislocation and rotation of the soil particles. The force chain, stress field, coordination number, and porosity were similar in the shear process and showed a concentrated distribution in the opposite direction of the shear motion, which reflected the consistency of the microcosmic response of the particles under the action of macroscopic external forces. The regression equations for the temperature, cohesion, and friction coefficient in this study can be used to simulate the shear behavior of frozen soil-concrete interfaces under different temperatures and normal stresses.</div></div>","PeriodicalId":10522,"journal":{"name":"Cold Regions Science and Technology","volume":"229 ","pages":"Article 104342"},"PeriodicalIF":3.8,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142531298","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-22DOI: 10.1016/j.coldregions.2024.104351
Jean-Denis Brassard, Sarah Sobhani, Maria-Lucia Loaiza Osorio, Gelareh Momen
The impact of winter on exposed structures and transportation poses significant dangers and costs to various industries, particularly the transportation sector. Icephobic surfaces are currently being developed to reduce winter-related impacts. Creating such surfaces requires considering various factors, including reducing and preventing ice accumulation, significantly decreasing ice adhesion, and/or delaying water solidification. Although established methods such as centrifugal force and push-off tests exist for measuring ice adhesion, the results may not always correlate or offer the needed information for specific applications. To better assess icephobic properties, we have developed a novel device called the human motion–inspired automated apparatus (HMA) that mimics manual de-icing performed by humans in a scraping mode. The primary objective of the HMA is to emulate human removal of ice-covered surfaces, providing a more realistic evaluation of icephobic properties according to the ease of ice removal. This apparatus aims to revolutionize icephobic material assessment by offering improved accuracy, repeatability, and versatility in testing. We developed a unique procedure using low icing conditions, which are challenging to evaluate using conventional methods, and assessed four surfaces: aluminum as a reference, an epoxy-based hydrophilic coating, a hydrophobic silicone elastomer coating, and a hydrophobic epoxy–silicone coating. Our HMA characterizes surfaces according to several crucial parameters, including the normal force required to initiate ice scraping removal, the maximum force achieved, the angle of attack, and the equivalent force, all consistent with validation tests conducted by humans. Among the evaluated surfaces, the silicone coating required the lowest normal force, and the epoxy–silicone coating had the lowest maximum and equivalent forces. Our HMA results align well with validation tests conducted by humans. The HMA enables evaluating various critical icing conditions and promises a broad range of applications in research and development.
{"title":"New insights into icephobic material assessment: Introducing the human motion–inspired automated apparatus (HMA)","authors":"Jean-Denis Brassard, Sarah Sobhani, Maria-Lucia Loaiza Osorio, Gelareh Momen","doi":"10.1016/j.coldregions.2024.104351","DOIUrl":"10.1016/j.coldregions.2024.104351","url":null,"abstract":"<div><div>The impact of winter on exposed structures and transportation poses significant dangers and costs to various industries, particularly the transportation sector. Icephobic surfaces are currently being developed to reduce winter-related impacts. Creating such surfaces requires considering various factors, including reducing and preventing ice accumulation, significantly decreasing ice adhesion, and/or delaying water solidification. Although established methods such as centrifugal force and push-off tests exist for measuring ice adhesion, the results may not always correlate or offer the needed information for specific applications. To better assess icephobic properties, we have developed a novel device called the human motion–inspired automated apparatus (HMA) that mimics manual de-icing performed by humans in a scraping mode. The primary objective of the HMA is to emulate human removal of ice-covered surfaces, providing a more realistic evaluation of icephobic properties according to the ease of ice removal. This apparatus aims to revolutionize icephobic material assessment by offering improved accuracy, repeatability, and versatility in testing. We developed a unique procedure using low icing conditions, which are challenging to evaluate using conventional methods, and assessed four surfaces: aluminum as a reference, an epoxy-based hydrophilic coating, a hydrophobic silicone elastomer coating, and a hydrophobic epoxy–silicone coating. Our HMA characterizes surfaces according to several crucial parameters, including the normal force required to initiate ice scraping removal, the maximum force achieved, the angle of attack, and the equivalent force, all consistent with validation tests conducted by humans. Among the evaluated surfaces, the silicone coating required the lowest normal force, and the epoxy–silicone coating had the lowest maximum and equivalent forces. Our HMA results align well with validation tests conducted by humans. The HMA enables evaluating various critical icing conditions and promises a broad range of applications in research and development.</div></div>","PeriodicalId":10522,"journal":{"name":"Cold Regions Science and Technology","volume":"229 ","pages":"Article 104351"},"PeriodicalIF":3.8,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142531297","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The complexities of permafrost changes, driven by climate warming and engineering activities, coupled with challenges in data acquisition, make it crucial and challenging to accurately predict the artificial permafrost table, particularly for subgrades in high-temperature unstable permafrost regions. To address this, this study developed a hybrid machine learning model (RF-LSTM-XGBoost) for permafrost table prediction. By analyzing climate change and ground temperature data from various positions and depths along the subgrade in the Tuotuo River section of the Qinghai-Xizang Highway, the Spearman correlation coefficient method was initially used to determine the important influencing factors. Random Forest (RF), Long Short-Term Memory Neural Network (LSTM), and Extreme Gradient Boosting (XGBoost) models were used to predict the artificial permafrost table, and grid search and cross-validation methods were employed to optimize the hyperparameters of each model. A linear weighted combination method based on the minimum cumulative absolute error was utilized to merge the models, and its performance was compared with the individual RF, LSTM, and XGBoost models. Subsequently, the feature importance of the variables in the machine learning model was analyzed. The results indicated a strong correlation between artificial permafrost table changes and factors such as daily average atmospheric temperature, subgrade surface ground temperature, and subgrade surface ground heat flux during the freezing-thawing cycle. The combined model highlighted daily atmospheric temperature as the most influential predictor, followed by ground heat flux, with the surface ground temperature being less impactful. The combined model demonstrated improved predictive accuracy, with MSE, MAPE, RMSE, MAE, and R2 values of 0.003, 0.052, 0.0085, 0.029, and 0.989, respectively, surpassing those of individual models. This model offers a rapid, accurate, and reliable approach for permafrost table prediction, advancing subgrade stability research in challenging permafrost environments.
{"title":"Enhancing artificial permafrost table predictions using integrated climate and ground temperature data: A case study from the Qinghai-Xizang highway","authors":"Yu-Zhi Zhang , Shao-Jie Liang , Jian-Bing Chen , Meng Wang , Ming-Tao Jia , Ya-Ting Jiang","doi":"10.1016/j.coldregions.2024.104341","DOIUrl":"10.1016/j.coldregions.2024.104341","url":null,"abstract":"<div><div>The complexities of permafrost changes, driven by climate warming and engineering activities, coupled with challenges in data acquisition, make it crucial and challenging to accurately predict the artificial permafrost table, particularly for subgrades in high-temperature unstable permafrost regions. To address this, this study developed a hybrid machine learning model (RF-LSTM-XGBoost) for permafrost table prediction. By analyzing climate change and ground temperature data from various positions and depths along the subgrade in the Tuotuo River section of the Qinghai-Xizang Highway, the Spearman correlation coefficient method was initially used to determine the important influencing factors. Random Forest (RF), Long Short-Term Memory Neural Network (LSTM), and Extreme Gradient Boosting (XGBoost) models were used to predict the artificial permafrost table, and grid search and cross-validation methods were employed to optimize the hyperparameters of each model. A linear weighted combination method based on the minimum cumulative absolute error was utilized to merge the models, and its performance was compared with the individual RF, LSTM, and XGBoost models. Subsequently, the feature importance of the variables in the machine learning model was analyzed. The results indicated a strong correlation between artificial permafrost table changes and factors such as daily average atmospheric temperature, subgrade surface ground temperature, and subgrade surface ground heat flux during the freezing-thawing cycle. The combined model highlighted daily atmospheric temperature as the most influential predictor, followed by ground heat flux, with the surface ground temperature being less impactful. The combined model demonstrated improved predictive accuracy, with MSE, MAPE, RMSE, MAE, and R<sup>2</sup> values of 0.003, 0.052, 0.0085, 0.029, and 0.989, respectively, surpassing those of individual models. This model offers a rapid, accurate, and reliable approach for permafrost table prediction, advancing subgrade stability research in challenging permafrost environments.</div></div>","PeriodicalId":10522,"journal":{"name":"Cold Regions Science and Technology","volume":"229 ","pages":"Article 104341"},"PeriodicalIF":3.8,"publicationDate":"2024-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142531296","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-05DOI: 10.1016/j.coldregions.2024.104338
Haiqiang Jiang , Xingchao Liu , Yuwei Chen , Enliang Wang , Qiang Fu , Junlin He , Hua Zhong
Frost damage is one of the main factors affecting the stability of canal slopes in cold regions. To alleviate the damage, laying protective layers during the construction process has become an indispensable measure. In this study, two slope models were constructed using polyester geotextiles (slope I) and composite geomembranes (slope II) as the protective layer. Additionally, the insulation board in the control group were laid on specific section to examine their anti-frost effect. The temperature, frozen depth, and frost deformations of slope models during the freeze-thaw process were recorded and analyzed. Results suggest that the temperature of slope II is relatively lower than that of slope I in the freezing process. The temperature reduction at all monitoring sections of slope II are larger than that of slope I. The slope I exhibits a significant decrease in maximum frozen depth and maximum frost deformation. In particular, the section with the maximum frost deformation is independent of the type of protective layer, which all occurs in the middle of the slopes. The maximum frost deformations of slope models are 33.60 mm and 37.69 mm, respectively after laying the polyester geotextiles and composite geomembranes. Therefore, the polyester geotextiles have more advantages in reducing frost deformation than composite geomembranes. Additionally, if the insulation board and polyester geotextiles are laid together inside the slope, the maximum frost deformation can be further reduced to 9.72 mm. This study will help in the design and construction of canal slopes in cold regions.
冻害是影响寒冷地区运河边坡稳定性的主要因素之一。为了减轻冻害，在施工过程中铺设保护层已成为一项不可或缺的措施。本研究使用聚酯土工织物（边坡 I）和复合土工膜（边坡 II）作为保护层，建造了两个边坡模型。此外，还在特定地段铺设了对照组的保温板，以检验其防冻效果。记录并分析了冻融过程中边坡模型的温度、冻结深度和霜冻变形。结果表明，在冻结过程中，斜坡 II 的温度相对低于斜坡 I。边坡 I 的最大冻结深度和最大冻胀变形均有显著下降。特别是，最大冻胀变形段与保护层类型无关，均出现在斜坡中部。在铺设聚酯土工织物和复合土工膜后，边坡模型的最大冻胀变形分别为 33.60 毫米和 37.69 毫米。因此，聚酯土工织物在减少冻害变形方面比复合土工膜更有优势。此外，如果将保温板和聚酯土工织物一起铺设在斜坡内，最大冻胀变形可进一步减小到 9.72 毫米。这项研究将有助于寒冷地区运河边坡的设计和施工。
{"title":"Model test investigation on heat and deformation behaviors of canal slopes with protective layers caused by freeze-thaw action","authors":"Haiqiang Jiang , Xingchao Liu , Yuwei Chen , Enliang Wang , Qiang Fu , Junlin He , Hua Zhong","doi":"10.1016/j.coldregions.2024.104338","DOIUrl":"10.1016/j.coldregions.2024.104338","url":null,"abstract":"<div><div>Frost damage is one of the main factors affecting the stability of canal slopes in cold regions. To alleviate the damage, laying protective layers during the construction process has become an indispensable measure. In this study, two slope models were constructed using polyester geotextiles (slope I) and composite geomembranes (slope II) as the protective layer. Additionally, the insulation board in the control group were laid on specific section to examine their anti-frost effect. The temperature, frozen depth, and frost deformations of slope models during the freeze-thaw process were recorded and analyzed. Results suggest that the temperature of slope II is relatively lower than that of slope I in the freezing process. The temperature reduction at all monitoring sections of slope II are larger than that of slope I. The slope I exhibits a significant decrease in maximum frozen depth and maximum frost deformation. In particular, the section with the maximum frost deformation is independent of the type of protective layer, which all occurs in the middle of the slopes. The maximum frost deformations of slope models are 33.60 mm and 37.69 mm, respectively after laying the polyester geotextiles and composite geomembranes. Therefore, the polyester geotextiles have more advantages in reducing frost deformation than composite geomembranes. Additionally, if the insulation board and polyester geotextiles are laid together inside the slope, the maximum frost deformation can be further reduced to 9.72 mm. This study will help in the design and construction of canal slopes in cold regions.</div></div>","PeriodicalId":10522,"journal":{"name":"Cold Regions Science and Technology","volume":"228 ","pages":"Article 104338"},"PeriodicalIF":3.8,"publicationDate":"2024-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142420184","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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