Research in Cold and Arid Regions最新文献

{"title":"A spring-like interface between saturated frozen soil and circular tunnel lining under the moving load in cold regions without considering frost heave","authors":"WenHua Chen,&nbsp;ShuoCheng Zhang","doi":"10.1016/j.rcar.2023.02.003","DOIUrl":"10.1016/j.rcar.2023.02.003","url":null,"abstract":"<div><p>The vibration of underground or buried piping during construction and long-term operation causes secondary disasters, and becomes more complex when tubes are buried in cold regions. The interface between saturated frozen soil and lining is regarded as a thin spring-like layer whose thickness could be negligible. In this paper, the dynamic response of saturated frozen soil is studied in frequency domain by using the Helmholtz composition and Fourier transform to obtain analytical solutions of the radial and axial displacement, as well as expressions of the stiffness coefficient (<em>K</em>_r) and damping coefficient (<em>C</em>_r) of the spring-like interface. Numerical results indicate that <em>K</em>_r and <em>C</em>_r are related to physical properties of the lining and its surrounding soil, and the coefficients of the spring<strong>-</strong>like model could be changed by adjusting lining parameters to improve structure stability under the same load conditions. Also, the viscoelastic contact surface of the spring<strong>-</strong>like model is considered to have less effect on the surrounding soil than that when the lining has complete contact with the soil under load. The degree of soil freezing significantly affects the axial and radial displacement of the soil when the interface between lining and unsaturated frozen soil is taken into consideration.</p></div>","PeriodicalId":53163,"journal":{"name":"Research in Cold and Arid Regions","volume":"14 6","pages":"Pages 377-392"},"PeriodicalIF":0.0,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2097158323000095/pdfft?md5=7396bc67f565a2130b63f8fb258ebc0c&pid=1-s2.0-S2097158323000095-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43258832","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of the frozen layer on the stability of cut soil slopes during seasonal freezing and thawing","authors":"Ting Wang ,&nbsp;HaiLiang Jia ,&nbsp;Qiang Sun ,&nbsp;GuoYu Li","doi":"10.1016/j.rcar.2022.12.001","DOIUrl":"10.1016/j.rcar.2022.12.001","url":null,"abstract":"<div><p>Research on the stability of soil slopes in seasonally frozen regions has mainly focused on slope failures during the thawing window. There are few studies on slope stability during the freezing window and its subsequent influence on slope failure in the next thawing window. In this paper, soil strength was tested during freezing and thawing to obtain temperature-dependent strength parameters for the simulation of slope stability. Then, the slope's temperature field over an entire year was accurately simulated so that characteristics of the frozen layer could be determined at any time. Based on the above results, the progressive failure modes of frozen soil slopes are discussed. The results show that: 1) during the freezing window, depth of the frozen soil layer increases, as does the slope's safety factor, while a yield zone propagates towards the slope shoulder. (2) During the thawing window, the frozen soil layer shrinks in depth while the yield zone continuously expands, which decreases the safety factor. Comprehensive analysis of these results indicate that the frozen layer provides a “toe-locking effect” that increases the safety factor during the freezing window, while it also provides a “dragging effect” that propagates the yield zone towards the slope shoulder. During the thawing window, the “toe-locking effect” gradually diminishes; a continuous sliding surface is formed, which lead to a landslide. The frozen soil layer of the freezing window accelerates the slope sliding in the thawing window.</p></div>","PeriodicalId":53163,"journal":{"name":"Research in Cold and Arid Regions","volume":"14 5","pages":"Pages 281-292"},"PeriodicalIF":0.0,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2097158322000209/pdfft?md5=883845808260fa91012fb1d59d392413&pid=1-s2.0-S2097158322000209-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42804485","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study on stability of permafrost slopes during thawing","authors":"Heng Zhang ,&nbsp;XiaoDong Liu ,&nbsp;Cheng Cao ,&nbsp;XiaoWu Ma ,&nbsp;XiaoLiang Yao ,&nbsp;WenLi Wang ,&nbsp;RuoXing Zhou ,&nbsp;LiPing Wang","doi":"10.1016/j.rcar.2022.12.004","DOIUrl":"10.1016/j.rcar.2022.12.004","url":null,"abstract":"<div><p>A numerical simulation platform that analyzes the variation of the slope factor of safety with time instantaneously is proposed based on heat conduction theory to study the law of stability development of permafrost slopes during thawing. This platform considers ice-water phase change, elastoplastic constitutive behavior and strength reduction in thawing permafrost and can evaluate the factor of safety of permafrost slopes with different slope angles and water contents. Results indicate that under different slope angles and water contents, the evolution of the factor of safety with time displays two stages: nonlinearly decreasing at first and then essentially remaining constant. During the decreasing stage, the plastic slip line overlaps with the thawing front. In this stage, the self-weight of the post-thawed permafrost layer increases continuously while the shear strength of the frozen-thaw interface keeps unchanged. This is the main reason leading to the decrease in the factor of safety. In the second stage, the thawing depth increases continuously while the position of the plastic slip line remains unchanged, resulting in a constant safety factor stage.</p></div>","PeriodicalId":53163,"journal":{"name":"Research in Cold and Arid Regions","volume":"14 5","pages":"Pages 293-297"},"PeriodicalIF":0.0,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2097158322000234/pdfft?md5=4de04def3e6cb8bcda13e1498ae818db&pid=1-s2.0-S2097158322000234-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47646719","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical evaluation of the effectiveness of frost heave mitigation strategies for chilled arctic gas pipelines","authors":"XinZe Li ,&nbsp;QingBai Wu ,&nbsp;HuiJun Jin ,&nbsp;Rui Shi ,&nbsp;Gang Wu ,&nbsp;YaPeng Cao","doi":"10.1016/j.rcar.2022.12.002","DOIUrl":"10.1016/j.rcar.2022.12.002","url":null,"abstract":"<div><p>To prevent the thawing of ice-rich permafrost, it is suggested that gas should be transported in a chilled state (below the freezing temperature) in pipelines buried in permafrost. However, frost heave occurs when water migrates towards the chilled pipeline and ice lenses grow underneath the pipe. This might endanger the integrity of the pipeline and the environment as well. Therefore, innovative frost heave mitigation measures are required when designing the pipeline, especially those sections in discontinuous permafrost or near the compressor stations. The ground temperature field in response to the operation of a proposed chilled gas pipeline traversing permafrost regions in Alaska was simulated by a pipe-soil thermal interaction geothermal model. Frost heave mitigation measures, including insulation around the pipe, flat slab insulation under the pipe, and heating cables combined with slab insulation, were evaluated for chilled pipeline operation in seasonally varying ambient temperatures. The numerical results show that the minimum temperature of the observation point at 2.5 m below the pipe bottom increases by 17%, 29%, and 48% when the thermal conductivity of the outer insulation layer is 0.1, 0.05, and 0.02 W/(m·K), respectively. For flat slab insulation, the thermal field is less sensitive to varying slab thicknesses than to varying thermal conductivity, implying the thermal conductivity, not the thickness, is the crucial factor. Additionally, the heat flow could be redirected from vertical to horizontal by flat slab insulation. The electrical heating cables could be regarded as a new heat source to balance the heat removal rate of the soil around the chilled pipe. The minimum temperature of the observation point at 1.1 m below the bottom of the pipe increases from −15.2 °C to −3.0, 1.5, and 7.5 °C, corresponding to the heating cable power of 20, 30, and 40 W, respectively, with the power of 30 W deemed appropriate for the study case. It is concluded that heating cables in combination with insulation slabs could be adopted to regulate the temperature field around the chilled pipeline efficiently and economically. The advantages of this combination include redirecting the heat flow and eliminating frost in the soil underlying the pipe. These approaches could be considered for applications in gas pipeline projects in arctic and alpine/high-plateau permafrost regions.</p></div>","PeriodicalId":53163,"journal":{"name":"Research in Cold and Arid Regions","volume":"14 5","pages":"Pages 338-345"},"PeriodicalIF":0.0,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2097158322000210/pdfft?md5=f133d7f7ad6a80e4b274242ee6a78bc2&pid=1-s2.0-S2097158322000210-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46184289","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental study on mesostructural damage evolution of sandstone subjected to freeze-thaw cycling under uniaxial compression","authors":"Hui Liu ,&nbsp;SenLei Han ,&nbsp;GengShe Yang ,&nbsp;Yuan Zhang ,&nbsp;JinJie Yu ,&nbsp;ZongXin Feng","doi":"10.1016/j.rcar.2022.12.007","DOIUrl":"10.1016/j.rcar.2022.12.007","url":null,"abstract":"<div><p>In perennially frozen or seasonally frozen soil regions, freeze-thaw cycling adversely impacts the mechanical properties of rock mass, resulting in landslides, rock erosion, and other geological disasters. The microscopic damage evolution law of loaded sandstone under the freeze-thaw cycle is analyzed by conducting Nuclear Magnetic Resonance (NMR) and uniaxial compression acoustic emission (AE) experiments. The experimental results have shown that: (1) Freeze-thaw cycling increases sandstone's internal pores, enlarges the pore size, and modifies the original pore distribution. (2) The damage due to freeze-thaw cycling is positively correlated with the initial damage to the rock, and the damage on the rock surface is more severe than inside the rock sample. (3) Freeze-thaw cycling negatively impacts the mechanical properties of sandstone, and the elastic deformation stage of sandstone gradually decreases as the number of freeze-thaw cycles increases and gradually transitions from brittle failure to ductile failure. (4) The characteristic parameters of AE ringing count and accumulated energy can reveal the severity of freeze-thaw damage and the dynamic evolution process, and the damage development rate exhibits abrupt changes at critical moments. After five freeze-thaw cycles, the damage development rate rises suddenly, as manifested by a sharp increase in the frequency and energy of AE events. High-energy AE events frequently occur during the rapid expansion period of damage, which can be adopted as an essential reference for damage propagation and aggravation.</p></div>","PeriodicalId":53163,"journal":{"name":"Research in Cold and Arid Regions","volume":"14 5","pages":"Pages 317-328"},"PeriodicalIF":0.0,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S209715832200026X/pdfft?md5=8b28fa3df949a0d44a254a268700474c&pid=1-s2.0-S209715832200026X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46303381","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical study on surrounding rock mass temperature field of Kangding tunnel no. 2 considering wind flow","authors":"Hui Liu ,&nbsp;ZongXin Feng ,&nbsp;GengShe Yang ,&nbsp;Long Jin ,&nbsp;JinJie Yu","doi":"10.1016/j.rcar.2022.12.005","DOIUrl":"10.1016/j.rcar.2022.12.005","url":null,"abstract":"<div><p>Based on the Kangding Tunnel No. 2 project, this study analyzes the heat exchange between air and the rock mass surrounding the tunnel under wind flow by the finite difference method. The influence of factors on the temperature field of a tunnel in cold regions, including ventilation and initial conditions, is investigated. The results show that: 1) The lower the air temperature, the greater the wind speed, the larger the rock mass temperature influence circle and the greater the frozen depth; 2) When the wind speed is less than 3 m/s, its change has an obvious impact on the rock mass temperature; 3) For every drop of 5 °C in air temperature, the frozen depth increases by about 5 m, indicating that the air temperature is an essential factor affecting the rock mass temperature regime; 4) The higher the initial rock mass temperature is, the smaller the influence circle on the rock mass is. And to a certain extent, it determines the temperature distribution in the rock mass within a specific range from the wall surface.</p></div>","PeriodicalId":53163,"journal":{"name":"Research in Cold and Arid Regions","volume":"14 5","pages":"Pages 298-306"},"PeriodicalIF":0.0,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2097158322000246/pdfft?md5=a8cf195f4fcdf893630c0bcc96661a1c&pid=1-s2.0-S2097158322000246-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42852535","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical simulation of frost jacking response of a single pile considering hydro-thermo-mechanical coupling","authors":"XingYu Wang ,&nbsp;Dan Chang ,&nbsp;JianKun Liu","doi":"10.1016/j.rcar.2022.12.006","DOIUrl":"10.1016/j.rcar.2022.12.006","url":null,"abstract":"<div><p>Permafrost is widely distributed in China and around the world. In permafrost regions, soil frost heave and thawing are severe and frequent, and can destabilize pile foundations. To this end, a finite element model of a single pile in frozen soil is established to investigate the frost heave and frost jacking response to ensure its safety in the Qinghai-Tibet Plateau. Firstly, a hydro-thermal coupling model of a single pile in frozen soil is established based on coupling parameters and initial and boundary conditions. Then the temperature and moisture distributions are analyzed through the established coupling model. A hydro-thermo-mechanical coupling model is developed by importing the ice content and temperature results. Simulation results indicate that the amount of frost heave is greater at locations closer to the ground surface, and the displacement is smaller for frozen soil that is closer to the side of the pile. The results on frost jacking behavior of piles from this study can serve as a reference for the design, construction and maintenance of foundations.</p></div>","PeriodicalId":53163,"journal":{"name":"Research in Cold and Arid Regions","volume":"14 5","pages":"Pages 307-316"},"PeriodicalIF":0.0,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2097158322000258/pdfft?md5=b16c6ab8418b14214bb268675898bb56&pid=1-s2.0-S2097158322000258-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44663516","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical modelling of vibration response in loess hills due to a high-speed train on railway viaduct","authors":"WuJian Yan ,&nbsp;Hang Zhang ,&nbsp;HaiZhong Zheng ,&nbsp;ZhiJian Wu ,&nbsp;XinXin Tian","doi":"10.1016/j.rcar.2022.12.003","DOIUrl":"10.1016/j.rcar.2022.12.003","url":null,"abstract":"<div><p>In order to accurately analyze vibration characteristics and site effects of loess hills under moving load of a high-speed train, four types of loess hill models under railway viaduct was established by ABAQUS of finite element analysis software by field test. The dynamic response and stability of loess hills under two different vibration sources under high-speed train load were studied by using two-dimensional equivalent linear response time-history analysis, and the influence of the mechanical parameters of loess on the vibration of different types of loess hill was analyzed. Results show that there are obvious differences between peak displacement cloud maps of loess hills under the railway viaduct under gravity and train load action. We analyzed the influence of the change of elastic modulus on vibration propagation of soil of foundation and loess knoll, and found that the change of elastic modulus of soil in different position of foundation has more effect on vibration propagation than that of loess knoll soil. At the same time, the vertical acceleration cloud maps of the four types of loess hills are obviously different.</p></div>","PeriodicalId":53163,"journal":{"name":"Research in Cold and Arid Regions","volume":"14 5","pages":"Pages 329-337"},"PeriodicalIF":0.0,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2097158322000222/pdfft?md5=37cd06f3af3623ef7545212a95c3f5cb&pid=1-s2.0-S2097158322000222-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46431704","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The influence of the underpassing frozen connecting passage on the deformation of the existing tunnel","authors":"JunHao Chen ,&nbsp;Jian Zhang ,&nbsp;BiJian Chen ,&nbsp;Gen Lu","doi":"10.1016/j.rcar.2022.08.001","DOIUrl":"10.1016/j.rcar.2022.08.001","url":null,"abstract":"<div><p>Based on the engineering background of the contact channel between Shangyang and Gushan of Fuzhou Metro Line 2 undercrossing the existing tunnel line, the freezing temperature field of the contact channel, the displacement field of the existing tunnel line and the contact channel with different net distances and horizontal angles are analyzed by ANSYS finite element software and field measurement method. The obtained results indicate that during the freezing period, the temperature drops at different measuring holes are almost the same. The temperature near the bottom freezing tube drops faster than that far from the tube. It is found that the bilateral freezing technique improves the formation of the freezing wall in the intersection area. In this case, the intersection time of the cross-section is 7 days faster than that of the adjacent ordinary section. The change curve of the displacement of the surface uplift in different freezing periods with the distance from the center of the channel is “M” shaped. The maximum uplift displacement at 12 m from channel center is 25 mm. The vertical displacement of the measuring point located above the central axis of the connecting channel is large. The farther the point from the central axis, the smaller the corresponding vertical displacement. When the horizontal angle between the existing tunnel and the connecting channel is less than 60°, the existing vertical displacement of the tunnel changes rapidly with the horizontal angle, reaching 0.17 mm/°. Meanwhile, when the net distance is less than 6.1 m, the change rate of the vertical displacement of the tunnel is up to 2.4 mm/m.</p></div>","PeriodicalId":53163,"journal":{"name":"Research in Cold and Arid Regions","volume":"14 4","pages":"Pages 258-266"},"PeriodicalIF":0.0,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2097158322000015/pdfft?md5=ae6f26fc74cdd98e42cc927f299e77cb&pid=1-s2.0-S2097158322000015-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41946541","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of freeze tube deviation on the development of frozen wall during long cross-passage construction","authors":"JunHao Chen ,&nbsp;JianLin Wang ,&nbsp;LeXiao Wang ,&nbsp;Han Li ,&nbsp;MeiLin Chen","doi":"10.1016/j.rcar.2022.08.006","DOIUrl":"10.1016/j.rcar.2022.08.006","url":null,"abstract":"<div><p>This paper investigates the influence of the deviation in freeze pipe installation on the development of the frozen wall in long cross passages by numerical simulation with ANSYS software. The study case is from the artificial ground freezing project along the Fuzhou Metro Line 2 between Ziyang Station and Wuliting Station. Two freeze-pipe configurations, <em>i.e.</em>, one with perfectly aligned pipes without any deviation from design and another with randomly distributed deviation, are included for comparison. The effect of the random deviation in the freeze pipes on frozen wall interconnection time, the thickness of the frozen wall and the development of the temperature field is explored. For the characteristic section of the numerical model at a depth of 25 m, it is found that the frozen wall interconnection time under the random deviation case and no deviation case is 24 days and 18 days, respectively. The difference in the thickness of the thinnest frozen wall segment between the random deviation and no deviation cases is the largest in the early freezing stage (up to 0.75 m), which decreases with time to 0.31 m in the late freezing stage. The effects of random deviation are more significant in the early freezing stage and diminish as the freezing time increases.</p></div>","PeriodicalId":53163,"journal":{"name":"Research in Cold and Arid Regions","volume":"14 4","pages":"Pages 250-257"},"PeriodicalIF":0.0,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2097158322000064/pdfft?md5=7da361d0412fa0169f610750473e76f1&pid=1-s2.0-S2097158322000064-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43289843","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}