With climate change,high-altitude areas have been frequently observed with rising temperature and humidity levels,causing an increased likelihood of collapse of ice-rich slopes and threatening downstream human settlem...With climate change,high-altitude areas have been frequently observed with rising temperature and humidity levels,causing an increased likelihood of collapse of ice-rich slopes and threatening downstream human settlements and infrastructural assets.For example,two giant glaciers collapsed in 2016 in the Aru Range,Xizang,China,killing nine herders.Thus,developing numerical methodologies for stability analysis and reproducing the collapse and subsequent movement of landslide debris is imperative for proactively managing disaster risks.This study focuses on the two collapse events within the Aru Range,to numerically analyze the pre-collapse stability of the slopes and their movement processes after collapse.Compared with previous research,this study considers the impact of various environmental factors on the temperature and stability of the two Aru glaciers,especially the heat flux caused by subglacial seepage and geothermal activity.In addition to proving similar stability between the two slopes before the collapse and simulating the positions of headwalls after collapse,this study demonstrates the need of selecting the slope region for simulation,and clarifies the influence of subglacial water flow on the positions of headwalls.Finally,this study reproduces the transport distance of the sliding body and simulates the tsunami caused by the Aru glacial debris rushing into Aru Co Lake.An effective friction coefficient of 0.10-0.11 between the glacier debris and the terrain is proposed.This provides a reference for stability analyses and collapse consequence predictions of ice-rich slopes,aiding in developing strategies for hazard mitigation.展开更多
In contrast to glaciological studies in Mexico,periglacial studies are very recent and limited to the analysis of the general permafrost cover in the high mountains of the country.Although some of the studies on the r...In contrast to glaciological studies in Mexico,periglacial studies are very recent and limited to the analysis of the general permafrost cover in the high mountains of the country.Although some of the studies on the reconstruction of Pleistocene glaciers in Mexico mention the existence of rock glaciers,to date no work has been done to study their physical properties or determining their state of conservation.Since rock glaciers are the most important visible indicators of mountain permafrost(along with features such as gelifluction lobes and patterned ground)and given that the“Nevado”rock glacier is the main example of its kind in Mexico,this study analyzes its internal temperature and assesses its state of conservation.The investigation was carried out by drilling and thermal monitoring of rock profiles as well as air.The results indicate that at present,the“Nevado”seems to lack permafrost inside.Although there is evidence of surface freezing during the winter months in the upper part of the rock glacier,in the lower portion it is almost unnoticed;and in both parts the internal temperature shows a tendency towards positive values as depth increases,a situation that predominates throughout the year.In addition,according to the records of the climatological station located in the lower part of the rock glacier,although the annual rainfall regime could be favorable for the formation and feeding of interstitial or segregated ice,the air temperature conditions throughout the year prevent permanent freezing.The sum of the above determines that at present the“Nevado”could be considered as an inactive and relict-type rock glacier;the presence of vegetation on the surface of the debris that make it up corroborates its inactivity.展开更多
Ways of strengthening railway embankment basis on ice-rich permafrost are characterized by regulating cooling and warming factors for preservation of the basis in constantly frozen condition (with the help of snow rem...Ways of strengthening railway embankment basis on ice-rich permafrost are characterized by regulating cooling and warming factors for preservation of the basis in constantly frozen condition (with the help of snow removal, painting, sun-precipitation shed, cross-section cooling pipes, the film cover, and the longitudinal cooling device) or removing icy masses preventively from the basis and filling the cavities simultaneously with not subsiding soils (with use of jet geotechnology). Skilled-experimental development are shined on the basis of new ways of strengthening embankment basis on ice-rich frozen soils.展开更多
基金the financial support from the National Natural Science Foundation of China(Grant Nos.52039007 and 42477189)the Sichuan Science and Technology Program(Grant No.2024YFHZ0341).
文摘With climate change,high-altitude areas have been frequently observed with rising temperature and humidity levels,causing an increased likelihood of collapse of ice-rich slopes and threatening downstream human settlements and infrastructural assets.For example,two giant glaciers collapsed in 2016 in the Aru Range,Xizang,China,killing nine herders.Thus,developing numerical methodologies for stability analysis and reproducing the collapse and subsequent movement of landslide debris is imperative for proactively managing disaster risks.This study focuses on the two collapse events within the Aru Range,to numerically analyze the pre-collapse stability of the slopes and their movement processes after collapse.Compared with previous research,this study considers the impact of various environmental factors on the temperature and stability of the two Aru glaciers,especially the heat flux caused by subglacial seepage and geothermal activity.In addition to proving similar stability between the two slopes before the collapse and simulating the positions of headwalls after collapse,this study demonstrates the need of selecting the slope region for simulation,and clarifies the influence of subglacial water flow on the positions of headwalls.Finally,this study reproduces the transport distance of the sliding body and simulates the tsunami caused by the Aru glacial debris rushing into Aru Co Lake.An effective friction coefficient of 0.10-0.11 between the glacier debris and the terrain is proposed.This provides a reference for stability analyses and collapse consequence predictions of ice-rich slopes,aiding in developing strategies for hazard mitigation.
文摘In contrast to glaciological studies in Mexico,periglacial studies are very recent and limited to the analysis of the general permafrost cover in the high mountains of the country.Although some of the studies on the reconstruction of Pleistocene glaciers in Mexico mention the existence of rock glaciers,to date no work has been done to study their physical properties or determining their state of conservation.Since rock glaciers are the most important visible indicators of mountain permafrost(along with features such as gelifluction lobes and patterned ground)and given that the“Nevado”rock glacier is the main example of its kind in Mexico,this study analyzes its internal temperature and assesses its state of conservation.The investigation was carried out by drilling and thermal monitoring of rock profiles as well as air.The results indicate that at present,the“Nevado”seems to lack permafrost inside.Although there is evidence of surface freezing during the winter months in the upper part of the rock glacier,in the lower portion it is almost unnoticed;and in both parts the internal temperature shows a tendency towards positive values as depth increases,a situation that predominates throughout the year.In addition,according to the records of the climatological station located in the lower part of the rock glacier,although the annual rainfall regime could be favorable for the formation and feeding of interstitial or segregated ice,the air temperature conditions throughout the year prevent permanent freezing.The sum of the above determines that at present the“Nevado”could be considered as an inactive and relict-type rock glacier;the presence of vegetation on the surface of the debris that make it up corroborates its inactivity.
文摘Ways of strengthening railway embankment basis on ice-rich permafrost are characterized by regulating cooling and warming factors for preservation of the basis in constantly frozen condition (with the help of snow removal, painting, sun-precipitation shed, cross-section cooling pipes, the film cover, and the longitudinal cooling device) or removing icy masses preventively from the basis and filling the cavities simultaneously with not subsiding soils (with use of jet geotechnology). Skilled-experimental development are shined on the basis of new ways of strengthening embankment basis on ice-rich frozen soils.
