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| 1 | Numerical Simulation on Climate Effects of Freezing-Thawing Processes Using CCM3显示文摘A parameterization of soil freezing-thawing physics for use in the land-surface model of the National Center for Atmospheric Research(NCAR) Community Climate Model(CCM3) is developed and evaluated.The new parameterization scheme has improved the representation of physical processes in the existing land surface model.Numerical simulations using CCM3 with improved land-surface processes and with the original land-surface processes are compared against the NCEP reanalysis.It is found that the CCM3 version using the improved land surface model shows significant improvements in simulating precipitation in China during the summer season,the general circulation over East Asia,and wind fields over the Tibet Plateau.For the summer season,the improved model was able to better simulate the Indian summer monsoon components,including the mean northerly wind in the upper troposphere and mean southerly wind in the lower troposphere. | Chenghai Wang1,2*,Guodong Cheng3,Aijun Deng4,Wenjie Dong5 1.State Key Laboratory of Frozen Soil Engineering,Cold and Arid Regions Environmental and Engineering Research In-stitute,Chinese Academy of Sciences,Lanzhou Gansu 730000,China 2.State Key Laboratory of Cryosphere Sciences,Cold and Arid Regions Environmental and Engineering Research Insti-tute,Chinese Academy of Sciences,Lanzhou Gansu 730000,China 3.State Key Laboratory of Frozen Soil Engineering,Cold and Arid Regions Environmental and Engineering Research In-stitute,Chinese Academy of Sciences,Lanzhou Gansu 730000,China 4.Department of Meteorology,The Pennsylvania State University,University Park,PA 16802 5.State Key Laboratory of Earth Surface Processes and Ecology Resource,Beijing Normal University,Beijing 100875,China Chenghai Wang1,2*,Guodong Cheng3,Aijun Deng4,Wenjie Dong5 1.State Key Laboratory of Frozen Soil Engineering,Cold and Arid Regions Environmental and Engineering Research In-stitute,Chinese Academy of Sciences,Lanzhou Gansu 730000,China 2.State Key Laboratory of Cryosphere Sciences,Cold and Arid Regions Environmental and Engineering Research Insti-tute,Chinese Academy of Sciences,Lanzhou Gansu 730000,China 3.State Key Laboratory of Frozen Soil Engineering,Cold and Arid Regions Environmental and Engineering Research In-stitute,Chinese Academy of Sciences,Lanzhou Gansu 730000,China 4.Department of Meteorology,The Pennsylvania State University,University Park,PA 16802 5.State Key Laboratory of Earth Surface Processes and Ecology Resource,Beijing Normal University,Beijing 100875,China | 2008 | Research in Cold and Arid Regions2008，，1： | 44 |
| 2 | Spatiotemporal variability of permafrost degradation on the Qinghai-Tibet Plateau显示文摘Based on data from six meteorological stations in the permafrost regions, 60 boreholes for long-term monitoring of permafrost temperatures, and 710 hand-dug pits and shallow boreholes on the Qinghai-Tibet Plateau (QTP), the spatiotemporal variability of permafrost degradation was closely examined in relation to the rates of changes in air, surface, and ground temperatures. The de-cadal averages and increases in the mean annual air temperatures (MAATs) from 1961-2010 were the largest and most persistent during the last century. MAATs rose by 1.3℃, with an average increase rate of 0.03℃/yr. The average of mean annual ground surface temperatures (MAGSTs) increased by 1.3℃ at an average rate of 0.03℃/yr. The rates of changes in ground temperatures were -0.01 to 0.07℃/yr. The rates of changes in the depths of the permafrost table were -1 to +10 cm/yr. The areal extent of permafrost on the QTP shrank from about 1.50×106 km2 in 1975 to about 1.26×106 km2 in 2006. About 60% of the shrinkage in area of permafrost occurred during the period from 1996 to 2006. Due to increasing air temperature since the late 1980s, warm (>-1℃) permafrost has started to degrade, and the degradation has gradually expanded to the zones of transitory (-1 to -2℃) and cold (<-2℃) permafrost. Permafrost on the southern and southeastern plateau degrades more markedly. It is projected that the degradation of permafrost is likely to accelerate, and substantial changes in the distributive features and thermal regimes of permafrost should be anticipated. However, regarding the relationships between degrading permafrost and the degradation of rangelands, it is still too early to draw reliable conclusions due to inadequate scientific criteria and evidence. | HuiJun Jin DongLiang Luo ShaoLing Wang LanZhi Lv JiChun Wu | 2011 | Research in Cold and Arid Regions2011，3，4： | 16 |
| 3 | Frost heave control of fine round gravel fillings in deep seasonal frozen regions显示文摘Fine round gravel soil is widely employed in the subgrade of high speed railways in cold regions to prevent frost heaving and thawing. The lower the fines content in fine round gravel soil, the smaller the quantities of frost heaving and thawing, but compaction difficulty increases. This study is to obtain the optimum fines content and limited frost heaving and thawing. The fine round gravel soil filling (FRGSF) used in the Harbin-Qiqihaer Passenger Dedicated Line is taken as the study object. Influence of fines content on optimum water content, maximum dry density and frost heaving properties of FRGSF were studied by means of compaction and frost heaving tests. Results show that the maximum dry density of the FRGSF increases first and then decreases with an increase of fines content, namely there is an optimum fines content for easy compaction. The method of surface-vibratory instrument is fit for coarse-grained soils, and wet state of coarse-grained soil is in favor of compaction. Considering the relationship of fines content with maximum dry density and the frost heaving ratio of FRGSF, the fines content should be limited to within the range of 9%-10%, so that the frost heaving ratio is less than 1%, and the FRGSF is easily compacted. Water supply is proved to be an important factor influencing the amount of frost heaving of FRGSF. We also conclude that in the field, it is imperative to control waterproofing and drainage measures. | ZuRun Yue TianLiang Wang Chao Ma TieCheng Sun | 2013 | Research in Cold and Arid Regions2013，5，4： | 12 |
| 4 | Estimation of ground heat flux and its impact on the surface energy budget for a semi-arid grassland显示文摘Three approaches,i.e.,the harmonic analysis(HA) technique,the thermal diffusion equation and correction(TDEC) method,and the calorimetric method used to estimate ground heat flux,are evaluated by using observations from the Semi-Arid Climate and Environment Observatory of Lanzhou University(SACOL) in July,2008.The calorimetric method,which involves soil heat flux measurement with an HFP01SC self-calibrating heat flux plate buried at a depth of 5 cm and heat storage in the soil between the plate and the surface,is here called the ITHP approach.The results show good linear relationships between the soil heat fluxes measured with the HFP01SC heat flux plate and those calculated with the HA technique and the TDEC method,respectively,at a depth of 5 cm.The soil heat fluxes calculated with the latter two methods well follow the phase measured with the HFP01SC heat flux plate.The magnitudes of the soil heat flux calculated with the HA technique and the TDEC method are close to each other,and they are about 2 percent and 6 percent larger than the measured soil heat flux,respectively,which mainly occur during the nighttime.Moreover,the ground heat fluxes calculated with the TDEC method and the HA technique are highly correlated with each other(R2 = 0.97),and their difference is only about 1 percent.The TDEC-calculated ground heat flux also has a good linear relationship with the ITHP-calculated ground heat flux(R2 = 0.99),but their difference is larger(about 9 percent).Furthermore,compared to the HFP01SC direct measurements at a depth of 5 cm,the ground heat flux calculated with the HA technique,the TDEC method,and the ITHP approach can improve the surface energy budget closure by about 6 percent,7 percent,and 6 percent at SACOL site,respectively.Therefore,the contribution of ground heat flux to the surface energy budget is very important for the semi-arid grassland over the Loess Plateau in China.Using turbulent heat fluxes with common corrections,soil heat storage be-tween the surface and the heat flux plate can improve the surface energy budget closure by about 6 to 7 percent,resulting in a clo-sure of 82 to 83 percent at the SACOL site. | JinQing Zuo JieMin Wang JianPing Huang WeiJing Li GuoYin Wang HongLi Ren | 2011 | Research in Cold and Arid Regions2011，3，1： | 11 |
| 5 | Shrubs proliferated within a six-year exclosure in a temperate grassland—Spatiotemporal relationships between vegetation and soil variables显示文摘Overgrazing has been considered one of the major causes that trigger shrub encroachment of grassland.Proliferation of shrubs in grassland is recognized as an important indicator of grassland degradation and desertification.In China,various conservation measures,including enclosures to reduce livestock grazing,have been taken to reverse the trend of grassland desertification,yet shrubs have been reported to increase in the grasslands over the past decades.In late 2007,we set up a 400-m-by-50-m exclosure in a long-term overgrazed temperate grassland in Inner Mongolia,with the objective to quantify the spatiotemporal relationship between vegetation dynamics,soil variables,and grazing exclusion.Soil moisture was continuously monitored within the exclosure,and cover and aboveground biomass of the shrubs were measured inside the exclosure in 2007,2009,2010,2012,and 2013,and outside the exclosure in 2012 and 2013.We found the average shrub cover and biomass significantly increased in the six years by 103% and 120%,respectively.The result supported the hypothesis that releasing grazing pressure following long-term overgrazing tends to trigger shrub invasion into grassland.Our results,limited to a single gradient,suggest that any conservation measures with quick release of overgrazing pressure by enclosure or other similar means might do just the opposite to accelerate shrub encroachment in grassland.The changes in vegetation cover and biomass were regressed on the temporal average of the soil moisture content by means of the generalized least square technique to quantify the effect of the spatial autocorrelation.The result indicates that the grass cover and biomass significantly increased with the top,but decreased with the bottom layer soil moisture.The shrub cover and biomass,on the other hand,decreased with the top,but increased with bottom soil moisture,although the regression coefficients for the shrubs were not statistically significant.Hence this study supports the two-layered soil model which assumes grasses and shrubs use belowground resources in different depths. | Yong Zhang Qiong Gao Li Xu Mei Yu YuQiang Tian | 2014 | Research in Cold and Arid Regions2014，6，2： | 11 |
| 6 | Millennial-scale evolution of Hunshandake Desert and climate change during the Holocene in Inner Mongolia,northern China显示文摘The Hunshandake Desert is located at the northern edge of the East Asian monsoon region,and its natural environment is sensitive to monsoonal changes.Geologic records suggest that desert evolution corresponding to climate change had experienced several cycles in the Holocene,and the evolutionary process can be distinguished by four dominant stages according to changing trends of the environment and climate.(1) Holocene Ameliorative Period(11.0-8.7 cal ka B.P.),when the desert area gradually shrank following an approaching warm-wet climate and strengthening summer monsoon.(2) Holocene Optimum(8.7-6.0 cal ka B.P.),when the majority of moving sand dunes were stabilized and vegetation coverage quickly expanded in a suitable warm-wet climate and a strong summer monsoon.(3) Holocene Multivariate Period(6.0-3.5 cal ka B.P.),during a low-amplitude desert transformed between moving and stabilized types under alternating functions of cold-dry with warm-wet climate,and winter monsoon with summer monsoon.(4) Holocene Decay Period(since 3.5 cal ka B.P.),when the desert area tended to expand along with a weakened summer monsoon and a dry climate. | HeLing Jin Liang Ying Sun Zhong Sun | 2010 | Research in Cold and Arid Regions2010，2，6： | 10 |
| 7 | Acoustic experimental study of two types of rock from the Tibetan Plateau under the condition of freeze-thaw cycles显示文摘Under the condition of freeze-thaw cycles,two types of rocks(granite and andesite),used as slope protection for the Qinghai-Tibet Railway,were tested according to the special climatic conditions in the Tibetan Plateau,and their various damage processes in appearance were carefully observed.Observation results show that damage of andesite was more serious than that of granite.Using an acoustic instrument,ultrasonic velocity was tested.The changing trends of velocity with the number of freeze-thaw cycles were analyzed,and the freeze-thaw cycle damaging the physical and mechanical properties of rocks can be seen.According to the changing trends of ultrasonic velocity with the number of freeze-thaw cycles,mechanical parameters of rocks,such as dynamic elasticity modulus,Poisson's ratio,and dynamic bulk modulus were analyzed.It is found that they all have declining trends as the number of freeze-thaw cycles increases,and in particular,when the cycle number reaches a certain extent,the Poisson's ratio of rocks begins to become negative. | Hua Liu FuJun Niu ZhiYing Xu ZhanJu Lin Jian Xu | 2012 | Research in Cold and Arid Regions2012，4，1： | 10 |
| 8 | Review of the influence of freeze-thaw cycles on the physical and mechanical properties of soil显示文摘Seasonally frozen soil is a four-phase material and its physical-mechanical properties are more complex compared to the unfrozen soil. Its physical properties changes during the freeze-thaw process; repeated freeze-thaw cycles change the characteristics of soil, which can render the soil from an unstable state to a new dynamic equilibrium state. The freezing process changes the structure coupled between the soil particle arrangements, which will change the mechanical properties of the soil. The method of significance and interaction between different factors should be considered to measure the influence on the properties of soil under freeze-thaw cycles. | Dan Chang JianKun Liu | 2013 | Research in Cold and Arid Regions2013，5，4： | 9 |
| 9 | Rainfall interception by sand-stabilizing shrubs related to crown structure显示文摘On the edge of the Tengger Desert in northern China,revegetation has changed the landscape from moving dunes to stabilized dunes covered by shrubs,which further modifies the pattern of rainfall redistribution.To study rainfall interception loss by shrubs and its relationship to rainfall properties and crown structure,throughfalls passing through crowns of Artemisia ordosica Krash.and Caragana korshinskii Kom.were measured using nine PVC cups under the canopy of each of the two shrubs during 73 rain events over a three-year period,with total rainfall of 260.9 mm.Interception losses of gross rainfall by A.ordosica and C.korshinskii account for 15% and 27% of the total on a crown area basis,and 6% and 11% on a ground area basis,respectively.Individual throughfall(T) and interception(I) were significantly related to rainfall amount(Pg),duration(D),and intensity(R).Ratios of throughfall to rainfall(T/Pg) and interception to rainfall(I/Pg) were not only significantly related to Pg,D,and R,but also to shrub species,and interactions of species with crown volume(CV) and leaf area index(LAI).Under most rain events,interceptions by C.korshinskii with greater CV and LAI were significantly higher than those by A.ordosica,and more rainfall interception occurred at locations closer to the stems of the two shrubs.For C.korshinskii,I/Pg had a significant positive linear relation with CV and LAI,while T/Pg had a significant negative linear relation with them.CV has a greater influence on T/Pg and I/Pg than does LAI.Using a regression method,canopy water storage capacities are estimated to be 0.52 and 0.68 mm,and free throughfall coefficient to be 0.62 and 0.47 for A.ordosica and C.korshinskii,respectively. | ZhiShan Zhang 1*,XinRong Li 1,XueJun Dong 2,XiaoHong Jia 1,MingZhu He 1,HuiJuan Tan 1 1.Shapotou Desert Research and Experiment Station,Cold and Arid Regions Environmental and Engineering Research Institute,Chinese Academy of Sciences,Lanzhou,Gansu 730000,China.2.Central Grasslands Research Extension Center,North Dakota State University,Streeter,ND 58483,USA. | 2009 | Research in Cold and Arid Regions2009，1，2： | 9 |
| 10 | Validation of WRF model on simulating forcing data for Heihe River Basin显示文摘The research of coupling WRF(Weather Research and Forecasting Model)with a land surface model is enhanced to explore the interaction of the atmosphere and land surface;however,regional applicability of WRF model is questioned.In order to do the validation of WRF model on simulating forcing data for the Heihe River Basin,daily meteorological observation data from 15 sta-tions of CMA(China Meteorological Administration)and hourly meteorological observation data from seven sites of WATER(Watershed Airborne Telemetry Experimental Research)are used to compare with WRF simulations,with a time range of a whole year for 2008.Results show that the average MBE(Mean Bias Error)of daily 2-m surface temperature,surface pressure,2-m rela-tive humidity and 10-m wind speed were-0.19 °C,-4.49 hPa,4.08% and 0.92 m/s,the average RMSE(Root Mean Square Error)of them were 2.11 °C,5.37 hPa,9.55% and 1.73 m/s,and the average R(correlation coefficient)of them were 0.99,0.98,0.80 and 0.55,respectively.The average MBE of hourly 2-m surface temperature,surface pressure,2-m relative humidity,10-m wind speed,downward shortwave radiation and downward longwave were-0.16 °C,-6.62 hPa,-5.14%,0.26 m/s,33.0 W/m2 and-6.44 W/m2,the average RMSE of them were 2.62 °C,17.10 hPa,20.71%,2.46 m/s,152.9 W/m2 and 53.5 W/m2,and the average R of them were 0.96,0.97,0.70,0.26,0.91 and 0.60,respectively.Thus,the following conclusions were obtained:(1)regardless of daily or hourly validation,WRF model simulations of 2-m surface temperature,surface pressure and relative humidity are more reliable,especially for 2-m surface air temperature and surface pressure,the values of MBE were small and R were more than 0.96;(2)the WRF simulating downward shortwave radiation was relatively good,the average R between WRF simulation and hourly observation data was above 0.9,and the average R of downward longwave radiation was 0.6;(3)both wind speed and rainfall simulated from WRF model did not agree well with observation data. | XiaoDuo Pan Xin Li | 2011 | Research in Cold and Arid Regions2011，3，4： | 9 |
| 11 | Refreezing of cast-in-place piles under various engineering conditions显示文摘In the construction of the Qinghai-Tibet Power Transmission Line(QTPTL), cast-in-place piles(CIPPs) are widely applied in areas with unfavorable geological conditions. The thermal regime around piles in permafrost regions greatly affects the stability of the towers as well as the operation of the QTPTL. The casting of piles will markedly affect the thermal regime of the surrounding permafrost because of the casting temperature and the hydration heat of cement. Based on the typical geological and engineering conditions along the QTPTL, thermal disturbance of a CIPP to surrounding permafrost under different casting seasons, pile depths, and casting temperatures were simulated. The results show that the casting season(summer versus winter) can influence the refreezing process of CIPPs, within the first 6 m of pile depth. Sixty days after being cast, CIPPs greater than 6 m in depth can be frozen regardless of which season they were cast, and the foundation could be refrozen after a cold season. Comparing the refreezing characteristics of CIPPs cast in different seasons also showed that, without considering the ground surface conditions, warm seasons are more suitable for casting piles. With the increase of pile depth, the thermal effect of a CIPP on the surrounding soil mainly expands vertically, while the lateral heat disturbance changes little. Deeper, longer CIPPs have better stability. The casting temperature clearly affects the thermal disturbance, and the radius of the melting circle increases with rising casting temperature. The optimal casting temperature is between 2 °C and 9 °C. | Lei Guo QiHao Yu XiaoNing Li XinBin Wang YongYu Yue | 2015 | Research in Cold and Arid Regions2015，7，4： | 8 |
| 12 | Spatial distributions and interannual variations of snow cover over China in the last 40 years显示文摘By using the observational snow data of more than 700 weather stations,the interannual temporal and spatial characteristics of seasonal snow cover in China were analyzed.The results show that northern Xinjiang,northeastern China-Inner Mongolia,and the southwestern and southern portions of Tibetan Plateau are three regions in China with high seasonal snow cover and also an interannual anomaly of snow cover.According to the trend of both the snow depth and snow cover days,there are three changing patterns for the seasonal snow cover:The first type is that both snow depth and snow cover days simultaneously increase or decrease;this includes northern Xinjiang,middle and eastern Inner Mongolia,and so on.The second is that snow depth increases but snow cover days decrease;this type mainly locates in the eastern parts of the northeastern plain of China and the upper reaches of the Yangtze River.The last type is that snow depth decreases but snow cover days increase at the same time such as that in middle parts of Tibetan Plateau.Snow cover in China appears to have been having a slow increasing trend during the last 40 years.On the decadal scale,snow depth and snow cover days slightly increased in the 1960s and then decreased in the 1970s;they again turn to increasing in the 1980s and persist into 1990s. | ChengHai Wang ZhiLan Wang Yang Cui | 2009 | Research in Cold and Arid Regions2009，1，6： | 8 |
| 13 | Research on the temperature field of a partially freezing sand barrier with groundwater seepage显示文摘To study the distribution characteristics and variation regularity of the temperature field during the process of seepage freezing,a simulated-freezing test with seepage of Xuzhou sand was completed by using a model test developed in-house equipment.By means of three group freezing tests with different seepage velocities,we discovered the phenomenon of the asymmetry of the temperature field under the influence of seepage.The temperature upstream was obviously higher than that downstream.The temperature gradient upstream was also steeper than that downstream.With a higher seepage velocity,the asymmetry of the temperature field is more pronounced.The asymmetry for the interface temperature profile is more strongly manifest than for the main surface temperature profile.The cryogenic barrier section is somewhat'heartshaped'.With the increasing velocity of the seepage flow,the cooling rate of the soil decreases.It takes much time to reach the equilibrium state of the soil mass.In our study,seepage flow velocities of 0 m/d,7.5 m/d,and 15 m/d showed the soilcooling rate of 4.35°C/h,4.96°C/h,and 1.72°C/h,respectively. | Li Yan Lao Zhi Qiang Ji Liang Liang Huang Shang Jing Li | 2017 | Research in Cold and Arid Regions2017，9，3： | 7 |
| 14 | Average temperature calculation for straight single-row-piped frozen soil wall显示文摘The average temperature of frozen soil wall is an essential parameter in the process of design,construction,and safety management of artificial ground freezing engineering.It is the basis of calculating frozen soil's mechanical parameters,further prediction of bearing capacity and,ultimately,safety evaluation of the frozen soil wall.Regarding the average temperature of single-row-piped frozen soil wall,this paper summarizes several current calculation methods and their shortcomings.Furthermore,on the basis of Bakholdin's analytical solution for the temperature field under straight single-row-piped freezing,two new calculation models,namely,the equivalent trapezoid model and the equivalent triangle model,are proposed.These two approaches are used to calculate the average temperature of a certain cross section which indicates the condition of the whole frozen soil wall.Considering the possible parameter range according to the freezing pipe layout that might be applied in actual construction,this paper compares the average temperatures of frozen soil walls obtained by the equivalent trapezoid method and the equivalent triangle method with that obtained by numerical integration of Bakholdin's analytical solution.The results show that the discrepancies are extremely small and these two new approaches are better than currently prevailing methods.However,the equivalent triangle method boasts higher accuracy and a simpler formula compared with the equivalent trapezoid method. | XiangDong Hu SiYuan She RuiZhi Yu | 2011 | Research in Cold and Arid Regions2011，3，2： | 7 |
| 15 | OSL chronology and paleoclimatic implications of paleodunes in the middle and southwestern Qaidam Basin, Qinghai-Tibetan Plateau显示文摘Aeolian sediments are widely distributed in the Qaidam Basin, northeastern Qinghai-Tibetan Plateau (QTP). The paleodunes are mainly located at the southeastern, middle and southwestern Qaidam Basin. However, ages of paleodunes in the middle and southwestern Qaidam Basin have not been well studied, although they are close to and might connect to the evolution of salt lakes in the central basin. In this study, we use single aliquot regeneration (SAR) protocol of Optically Stimulated Luminescence (OSL) to date the dune sand in these two regions. The results show that: (1) Sand accumulation in these regions started at ca. 4-3 ka and lasted to ca. 0.5 ka when they were stabilized, due to the arid climate in the late Holocene. (2) The underlying fluvial sand was formed during deglaciation at 12.6±0.8 ka. (3) The stabilization periods of the paleodunes correspond to stages of glacier advance in the northeastern QTP, during which lower temperatures caused the decrease of evaporation and increase of the effective moisture, leading to an increase of vegetation cover and stabilization of the dunes. | LuPeng Yu ZhongPing Lai Ping An | 2013 | Research in Cold and Arid Regions2013，5，2： | 7 |
| 16 | Driving forces of land use and land cover change (LUCC) in the Zoige Wetland, Qinghai-Tibetan Plateau显示文摘The Zoige Wetland is located in the northeastern Qinghai-Tibetan Plateau, which is highly sensitive to global environment change and human disturbance because of its high elevation and cold environment, thus, it's a hotspot for land use and land cover change (LUCC) research. We used Landsat MSS images from 1975, Landsat ETM images from 2000, and Landsat TM images from 1990 and 2005 to assess the LUCC in the study area, using GIS techniques, as well as topographic, vegetation, and soil maps combined with field investigations. The monitoring result shows that the study area's environment degraded rapidly between 1975 and 2005, including wetland shrinkage from 5,308 km 2 to 4,980 km 2 , sandy land expansion from 112 km 2 to 137 km 2 , forest land decreasing from 5,686 km 2 to 5,443 km 2 , and grassland degradation from 12,309 km 2 to 10,672 km 2 . According to the analysis of meteorological data and social-economic statistical data, we concluded that the LUCC in the Zoige Wetland was caused by both natural and anthropogenic factors, but human activities were primarily responsible for the observed LUCC, thereby, we suggest human behaviors must be adjusted to control environmental degradation. | GuangYin Hu ZhiBao Dong JunFeng Lu ChangZhen Yan | 2012 | Research in Cold and Arid Regions2012，4，5： | 7 |
| 17 | Optimization of constitutive parameters of foundation soils k-means clustering analysis显示文摘The goal of this study was to optimize the constitutive parameters of foundation soils using a k-means algorithm with clustering analysis. A database was collected from unconfined compression tests, Proctor tests and grain distribution tests of soils taken from three different types of foundation pits: raft foundations, partial raft foundations and strip foundations.k-means algorithm with clustering analysis was applied to determine the most appropriate foundation type given the unconfined compression strengths and other parameters of the different soils. | Muge Elif Orakoglu Cevdet Emin Ekinci | 2013 | Research in Cold and Arid Regions2013，5，5： | 7 |
| 18 | The influence of freeze-thaw cycles on the granulometric composition of Moscow morainic clay显示文摘The freeze-thaw cycling process considerably changes the composition,structure,and properties of soils.Since the grain size is the most important factor in determining soil characteristics,our current research primarily aims to investigate dynamic changes of the soil fraction when exposed to freeze-thaw conditions.We observed two series of Moscow morainic clayey specimens(g QmII):(I) the original series,and(II) the remolded series.We subjected each series of soil specimens to different frequencies of freeze-thaw cycles(3,6,20,and 40 cycles),and we used granulometric tests to analyze both series before and after exposure to freeze-thaw conditions.As a result of our experiments,the granulometric compositions tended to be distributed evenly after 40 freeze-thaw processes(i.e.,content of fraction for 0.1–0.05 mm was increased after 40 freeze-thaw cycles) because the division of coarse grains and the aggregation of fine grains were synchronized during the freeze-thaw process.The soil grains in both series changed bi-directionally.In the original series,changes of the sand grains were conjugated with the clay grains,and in the remolded series,changes of the sand grains were conjugated with the silt grains,because potential energy difference caused the division and aggregation processes to relate to the counteraction process.The even distribution of soil grain size indicated the state of equilibrium or balance.The granulometric compositions were altered the most during the sixth freeze-thaw cycle,because the coefficient of the intensity variation of the grain fineness(Kvar) had its maximum value at that time. | Ze Zhang Vadim V.Pendin WenJie Feng ZhongQiong Zhang | 2015 | Research in Cold and Arid Regions2015，7，3： | 7 |
| 19 | Analysis of temperature field characteristics based on subgrade site measurements of Harbin-Qiqihar High-speed Railway in a deep seasonal frozen soil region显示文摘Recent years have seen a large number of high-speed railways built and will be built in seasonal frozen soil regions of China. Although high-speed railways are characterized by being fast, comfortable and safe, higher standards for deformation of the railways' frozen subgrade are required. Meanwhile, changes in subgrade soil temperatures are the main factors affecting the deformation of frozen subgrade. Therefore, this paper selected typical test subgrade sections of the Harbin–Qiqihar Line, a special line for passenger transport built in the deep seasonal frozen soil regions of China, to monitor field temperatures. Also, the temperature changing laws of railways' subgrade in this region was analyzed by using testing data, the aim of which is to provide a technical support for future design and construction of buildings and structures in a deep seasonal frozen soil region. | ZuRun Yue BoWen Tai TieCheng Sun | 2015 | Research in Cold and Arid Regions2015，7，5： | 7 |
| 20 | Prediction of land subsidence caused by groundwater exploitation in Hanoi, Vietnam, using multifactorial correlation analysis显示文摘Multifactorial correlation analysis is a new method used to predict the land subsidence caused by groundwater exploitation.This article introduces and applies the method to establish the function of the surface settlement rate(Vs) and the function of the time-dependent surface settlement(St) caused by groundwater exploitation, based on data acquired at three land subsidence monitoring stations in the Hanoi area of Vietnam. Comparison with actual monitoring data indicates that the prediction results are relatively close to the monitoring data. From this, we conclude that multifactorial correlation analysis is a reliable method and can be used to predict future land subsidence caused by groundwater exploitation in Hanoi. | Thinh Hong Phi Ludmila Aleksandrovna Strokova | 2013 | Research in Cold and Arid Regions2013，5，5： | 7 |
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