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考虑季节影响的地铁区间隧道围岩动态热交换研究

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施工技术（中英文） 2024年第10期53卷 44-50页

作者：姚庆夏才初宁波大学岩石力学研究所浙江宁波315211 宁波市能源地下结构重点实验室浙江宁波315211

为深化对地铁隧道热环境与围岩之间关系的认识,通过理论计算得到各季节围岩换热量作为间歇性热源边界对围岩进行加热,以模拟围岩和隧道热环境的动态变化,将其作为数值模型的热边界条件,建立三维地铁隧道围岩温度场模型,并与实测数据进... 详细信息

为深化对地铁隧道热环境与围岩之间关系的认识,通过理论计算得到各季节围岩换热量作为间歇性热源边界对围岩进行加热,以模拟围岩和隧道热环境的动态变化,将其作为数值模型的热边界条件,建立三维地铁隧道围岩温度场模型,并与实测数据进行了对比。结果表明,模拟结果与实测数据吻合较好,验证了该模型的可靠性。利用该模型对比分析了换热器对地铁区间隧道围岩长期温度场演化规律的影响。换热器在夏季能有效减小围岩温度的变化幅度,提高围岩的蓄热能力;在冬季能使围岩储存更多冷量,并可部分抵消区间隧道在下一年产生的热量,从而改善围岩的蓄冷能力。

关键词：地铁隧道围岩温度场热交换换热器

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上海软土地层中地铁联络通道冻结法施工的温度场发展特性

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城市轨道交通研究 2024年第1期27卷 80-86页

作者：赵昊楠夏才初王兴开绍兴文理学院土木工程学院绍兴312099 同济大学土木工程学院上海200092

[目的]为了在冻结法施工前预先判断冻结壁的发展情况,验证设计的合理性,从而科学地指导工程施工,需要研究上海地铁联络通道在软土地层中冻结法施工的温度场发展规律,并提出检验指标及经济指标。[方法]以上海轨道交通15号线某区间联络通... 详细信息

[目的]为了在冻结法施工前预先判断冻结壁的发展情况,验证设计的合理性,从而科学地指导工程施工,需要研究上海地铁联络通道在软土地层中冻结法施工的温度场发展规律,并提出检验指标及经济指标。[方法]以上海轨道交通15号线某区间联络通道为背景,对冻结壁厚度、土层温度、盐水温度及冻结过程进行分析,通过ABAQUS有限元软件建立全地层三维数值模型,预测冻结温度场发展特性,并与现场实测温度数据进行验证。[结果及结论]黏土层冻结帷幕平均发展速度为54.535 mm/d,粉质黏土层冻结帷幕平均发展速度为52.450 mm/d,黏土层比粉质黏土层冻结效果好;由于冻结管端头截面冻结效果较弱,以该截面处弱侧冻结壁厚度和平均温度作为冻结效果的检验指标,降低强度破坏可能性;盐水温度对冻结壁厚度发展的影响随温度的降低而减弱,其中-35~-30℃时经济效益最高;模拟结果与实测数据总体降温趋势一致,可较为真实地反映实际工程。

关键词：地铁隧道冻结法数值模拟联络通道瞬态温度场

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地铁隧道岩土体取热蓄冷系统的效果及参数分析

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施工技术（中英文） 2024年第5期53卷 83-89页

作者：姚曙光夏才初宁波大学岩石力学研究所浙江宁波315211 宁波市能源地下结构重点实验室浙江宁波315211

地铁运行后,由于隧道封闭性导致列车产生的热量无法及时散发或排出,使隧道周围岩土体温度不断上升、隧道内热环境不断恶化。为解决地铁隧道内热堆积问题,将岩土体取热蓄冷系统应用在地铁隧道内。在混凝土管片中布置热交换管,通过管内低... 详细信息

地铁运行后,由于隧道封闭性导致列车产生的热量无法及时散发或排出,使隧道周围岩土体温度不断上升、隧道内热环境不断恶化。为解决地铁隧道内热堆积问题,将岩土体取热蓄冷系统应用在地铁隧道内。在混凝土管片中布置热交换管,通过管内低温水流动降低混凝土管片和岩土体温度,从而为地铁隧道营造较舒适的热环境。采用流-热耦合数值模拟计算方法,评价系统运行效果,并计算水流速和系统运行模式对岩土体温度的影响。结果表明,该系统有效解决隧道内热堆积问题,可长期有效运行。

关键词：地铁热堆积换热器耦合数值模拟

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基于混凝土强度的高地热隧道隔热层厚度研究

铁道标准设计 2024年第4期68卷 161-167页

作者：郭利民段俊哲夏才初常文江中铁第一勘察设计院集团有限公司西安710043 同济大学地下建筑与工程系上海200092 宁波大学岩石力学研究所宁波315211 绍兴文理学院土木工程学院浙江绍兴312000 川藏铁路建设公司成都610036

随着“长大深”隧道的发展,越来越多高地热隧道得以建设。高地热作为典型的不良地质之一,不仅会给隧道施工带来不便,还会严重危害隧道结构的安全。为减小高温对高地热隧道的不利影响,首先,调研相关文献,明确了温度与衬砌混凝土强度之间... 详细信息

随着“长大深”隧道的发展,越来越多高地热隧道得以建设。高地热作为典型的不良地质之一,不仅会给隧道施工带来不便,还会严重危害隧道结构的安全。为减小高温对高地热隧道的不利影响,首先,调研相关文献,明确了温度与衬砌混凝土强度之间的关系;然后,以西部高原地区某高地热隧道为依托,使用Comsol数值模拟软件建立该隧道的温度场计算模型。通过数值计算得到各工况下衬砌混凝土的平均养护温度,并将其与强度相对应,并从保护衬砌混凝土强度的角度研究了各工况下不同厚度隔热层的作用。研究得到以下结论:(1)根据他人试验结果总结发现,隧道施工时应保证混凝土养护温度低于40℃,否则会严重降低衬砌混凝土的强度;(2)提出高地热环境隧道施工时隔热层的选取方案,55℃以下的地温段,无需使用隔热层;55~65℃地段,推荐使用3 cm隔热层;65~75℃地温段,使用5 cm隔热层;75~85℃地温段,若能保证洞内气温维持在28℃以内,使用5 cm隔热层,否则使用10 cm隔热层;高于85℃的地段,推荐使用10 cm隔热层。

关键词：高地热隧道隔热层厚度 Comsol数值模拟混凝土强度养护温度

Air tightness of compressed air storage energy caverns with polymer sealing layer subjected to various air pressures

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第8期15卷 2105-2116页

作者： Shikang Qin caichu xia Shuwei Zhou College of Civil Engineering Tongji UniversityShanghai200092China Institute of Rock Mechanics Ningbo UniversityNingbo315211China

During the operation of compressed air storage energy system,the rapid change of air pressure in a cavern will cause drastic changes in air density and permeability coefficient of sealing *** calculate and properly evaluate air tightness of polymer sealing caverns,the air-pressure-related air density and permeability must be *** this context,the high-pressure air penetration in the polymer sealing layer is studied in consideration of thermodynamic change of the cavern structure during the system *** air tightness model of compressed air storage energy caverns is then *** the model,the permeability coefficient and air density of sealing layer vary with air pressure,and the effectiveness of the model is verified by field data in two test ***,a compressed air storage energy cavern is taken as an example to understand the air *** air leakage rate in the caverns is larger than that using air-pressure-independent permeability coefficient and air density,which is constant and small in the previous leakage rate *** the operating pressure of 4.5-10 MPa,the daily air leakage in the compressed air storage energy cavern of Yungang Mine with high polymer butyl rubber as the sealing material is 0.62%,which can meet the sealing requirements of compressed air storage energy *** air tightness of the polymer sealing cavern is mainly affected by the cavern operating pressure,injected air temperature,cavern radius,and sealing layer *** cavern air leakage rate will be decreased to reduce the cavern operating pressure the injection air temperature,or the cavern radius and sealing layer thickness will be increased.

关键词： Compressed air storage energy Polymer sealing layer Air tightness Permeability coefficient Air density

Frost heave and freezing processes of saturated rock with an open crack under different freezing conditions

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Frontiers of Structural and Civil Engineering 2020年第4期14卷 947-960页

作者： Zhitao Lv caichu xia Yuesong WANG Ziliang LIN Department of Geotechnical Engineering Tongji UniversityShanghai 200092China Key Laboratory of Geotechnical and Underground Engineering of Minisry of Education Tongji UniversinShanghai 200092China

Frost heave experiments on saturated sandstone and tuff with an open crack are conducted under uniform and unidirectional freezing *** heave of crack in sandstone with high permeability is more significant under uniform freezing condition than that under unidirectional freezing ***,frost heave of crack in tuff with low permeability is more significant under unidirectional freezing *** illustrate the reasons for this phenomenon,a numerical model on the freezing processes of saturated rock with an open crack considering the latent heat of pore water and water in crack is proposed and confirmed to be *** results show that a frozen shell that blocks the migration of water in crack to rock develops first in the outer part of the rock before the freezing of water in crack under unifonn freezing ***,the migration path of water in crack to the unfrozen rock under freezing front exists under unidirectional freezing *** freezing process and permeability of rock together determine the migration of water in crack and lead to the different frost heave modes of crack for various permeable rocks under different freezing *** frost heave modes of crack in rock with low or high permeability are similar under uniform freezing condition because water migration is blocked by a frozen shell and is irrelevant to rock *** high permeability rock,the frost heave of crack will be weakened due to water migration under unidirectional freezing condition;however,the frost heave of crack would be more significant for low permeability rock because water migration is blocked under unidirectional freezing ***,the freezing condition and rock permeability determine the frost heave of rock with crack together,and this should be concerned in cold regions engineering applications.

关键词： frost heave rock with crack freezing process freezing condition frost heave mode

Modified ground response curve(GRC)in strain-softening rock mass based on the generalized Zhang-Zhu strength criterion considering over-excavation

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Underground Space 2021年第5期6卷 585-602页

作者： Chen Xu caichu xia Changling Han Institute of Rock Mechanics Ningbo UniversityNingboZhejiangChina Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghaiChina CCCC First Highway Consultants Co. LtdXi’anShaanxiChina

The ground response curve(GRC)depicts the relationship between support reaction force and ground displacement,which improves the understanding of ground-support interaction and provides important references to the tunnel ***,it is difficult to anticipate the tunneling-induced large deformation with sufficient reliability in soft rock with high geostress since the small strain theory is not *** large deformation occurs,the tunnel needs to be ***,the GRC should be modified considering the enlarged excavation radius since the actual excavation radius is usually greater than the designed *** overcome the shortcomings of small strain theory in recognizing ground-support interaction under large deformation circumstances,a new large strain numerical approach for modifying the GRC was proposed considering over-excavation in strain-softening rock masses based on the generalized Zhang-Zhu strength criterion.A case study was conducted based on the Lianchengshan tunnel in *** modified GRC was employed to investigate the ground-support behavior for different support schemes and to explore the applicability of the stress release *** with field tests,the proposed approach was *** comparing with GRCs proposed by previous work,the present modified GRC was proved to be superior to *** studies were conducted and it is found that over-excavation,for example,reserving a very large clearance between the surrounding rock and the support,is necessary to reduce ground pressure to a large *** yielding supports which can provide high support pressure during the process of deformation are highly recommended when tunneling in high geostress ***,if the initial geostress is not very high,it is not necessary to pursue unwarranted overexcavation since the ground pressure applied on the support is mainly the loosening stress when the deformation is *** support stiffness should be provi

关键词： Ground response curve Large strain Over-excavation Strain-softening Soft rock tunnel

Tunnels in squeezing clay-rich rocks

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Underground Space 2021年第4期6卷 432-445页

作者： Ketan Arora Marte Gutierrez Ahmadreza Hedayat caichu xia Civil and Environmental Engineering Colorado School of MinesGoldenCO 80401USA Geotechnical Engineering Tongji UniversityShanghai 200092China

Squeezing ground conditions,which can lead to severe loads in tunnels,have historically been associated with the presence of clay minerals in the *** the years,many methodologies have been proposed to predict squeezing in tunnels based on tunnel depth,in situ stress,ground mineralogy,and ground strength and deformation *** paper presents a comprehensive review of methodologies to predict tunnel squeezing in clay-rich rocks.A new methodology is proposed where ground conditions and squeezing potential are assessed based on the Stress History and Normalized Soil Engineering Properties(SHANSEP)approach adapted to clayrich rocks,Peck’s stability number and Hoek&Brown’s(1997)Geological Strength Index(GSI).A squeezing number S is suggested to classify ground conditions based on the level of squeezing that the ground may experience in response to ***,it is demonstrated that by combining the proposed classification system and an existing classification system for ground squeezing condition,an accurate estimate of tunnel strain can also be *** proposed method is applied to four case studies of tunnels in squeezing ground in shale and mudstone.

关键词： Squeezing ground High in situ stress Critical strain Clay-rich rocks Mudrock Shale Tunnels

钻孔埋管换热器用于寒区隧道消防管网加热保温的理论研究

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中南大学学报（自然科学版） 2023年第4期54卷 1472-1480页

作者：田凯旋夏才初徐英俊同济大学土木工程学院上海200092 宁波大学岩石力学研究所浙江宁波315211

为解决寒区隧道消防管冻结失效问题,提出一种基于钻孔埋管换热器的新型加热保温系统;基于非等温管道流模型,联立消防管段加热过程和埋管换热器换热理论,得到系统运行过程中流体温度分布的解析解。以林场隧道工程为背景,对加热段水温、... 详细信息

为解决寒区隧道消防管冻结失效问题,提出一种基于钻孔埋管换热器的新型加热保温系统;基于非等温管道流模型,联立消防管段加热过程和埋管换热器换热理论,得到系统运行过程中流体温度分布的解析解。以林场隧道工程为背景,对加热段水温、换热器换热效率等的变化规律进行理论分析与数值验证。研究结果表明:进、出口水温先降低后快速上升再缓慢下降,10 h时达到峰值;加热初期,轴向水温分布为“进口温度高、出口温度低、段中温度突变”,之后在4~5℃范围内近似呈均匀分布;随着系统的运行,换热器平均换热效率稳定在约15 W/m。系统连续运行对地温的影响范围不断扩大,钻孔附近地温不断降低。系统间歇运行模式由设定高限和低限控制,在间歇期内,围岩地温可得到一定程度的恢复,且换热器换热效率较连续运行工况下的高。水温、换热器换热效率等的理论计算结果与数值模拟结果吻合度较高,本文所提出的寒区隧道消防管网钻孔埋管换热保温系统可使消防管段水温维持在设定低限温度以上,节能高效,有一定的应用价值。

关键词：寒区隧道消防管加热保温系统钻孔埋管换热器非等温管道流地温间歇运行

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