Temperature field analysis of new pipe curtain freezing method in river embankment anti seepage reinforcement
-
摘要: 为了探究新型管幕冻结法是否能够对河堤进行有效的防渗加固,利用有限元软件基于温度场对新型管幕冻结法在防渗固堤中的应用展开研究,设置4条分析路径,对冻土帷幕的基本情况和各路径的冻结效果特征进行分析。结果表明:冻土帷幕自冻结管处形成后向周围蔓延,从第8天起,0.5 m深度上侧的冻土帷幕发展开始“加速”,相较于另一侧冻土帷幕,其发展更快、强度更高、冻结更密实。冻结完成后,0.5 m深度上侧冻土帷幕均匀密实,坡面上温度最低可降至−25.34℃,各观测点温度均在−24℃以下,最终冻结温度和降温速率均呈现出“M”形特征;堤面最快可在第11天开始冻结,在第14天冻土覆盖整个堤面,土体最终冻结温度与深度之间呈指数函数关系。管幕钢管边界冻结差异较大,最高温点与最低温点温度分别为−24.94℃和−2.89℃,相差约22℃,冻土帷幕最小厚度约0.78 m。所得结果可为将来的相关实际工程提供参考依据。Abstract: In order to explore whether the new pipe curtain freezing method can effectively strengthen the river embankment, this paper uses the finite element software to study the application of the new pipe curtain freezing method in anti-seepage and embankment reinforcement based on the temperature field, and sets up four analysis paths to deeply analyze the basic situation of the frozen soil curtain and the freezing effect characteristics of each path. The results show that the frozen soil curtain spreads around after it is formed at the freezing pipe. From the 8th day, the development of the frozen soil curtain on the upper side of 0.5 m depth begins to “accelerate”. Compared with the frozen soil curtain on the other side, it has faster development, higher strength and denser freezing. After freezing, the frozen soil curtain on the upper side of 0.5 m depth is uniform and dense; the minimum temperature on the slope can be reduced to −25.34℃, and the temperatures at each observation point are below −24℃. The final freezing temperature and cooling rate show “M” type characteristics. The embankment surface started to freeze at the earliest on the 11th day, and the frozen soil covered the whole embankment surface on the 14th day. The relationship between the final freezing temperature and depth is an exponential function. There is a great difference in the freezing of the steel pipe boundary of the pipe curtain. The highest temperature point and the lowest temperature point are −24.94℃ and −2.89℃ respectively, with a difference of about 22℃. The minimum thickness of the frozen soil curtain is about 0.78 m. The obtained results can provide reference basis for relevant practical projects in the future.
-
表 1 土体材料参数取值
Table 1 Material parameters of soils
密度/
(kg·m−3)导热系数/
(kJ·m−1·d−1·℃−1)比热容/
(kJ·kg−1·℃−1)相变潜热/
(103 kJ·m−3)未冻土 冻土 未冻土 冻土 1 857 124 152 1.736 1.35 1.04 表 2 盐水冻结方案
Table 2 Freezing plan of brine
时间/h 温度/℃ 时间/h 温度/℃ 0 18 360 −28 24 0 480 −28 120 −15 720 −28 240 −28 960 −28 -
[1] 曹斌翔. 河堤施工及软土地基处理初探[J]. 农业科技与信息,2017(14):97−98. CAO Binxiang. Preliminary study on river embankment construction and soft soil foundation treatment[J]. Agricultural Science–technology and Information,2017(14):97−98. [2] 宋玉杰,杨树林. 黄河大堤的现状、问题及加固措施[J]. 人民黄河,1993(12):13−16. SONG Yujie,YANG Shulin. Present situation,problems and strengthening measures of the Yellow River dike[J]. Yellow River,1993(12):13−16. [3] 杨志华,高美丽. 高压旋喷桩在河堤加固施工中的应用[J]. 水利技术监督,2019(5):229−231. YANG Zhihua,GAO Meili. Application of high pressure jet grouting pile in river embankment reinforcement construction[J]. Technical Supervision in Water Resources,2019(5):229−231.. doi: 10.3969/j.issn.1008-1305.2019.05.065 [4] 胡俊,杨平. 大直径杯型冻土壁温度场数值分析[J]. 岩土力学,2015,36(2):523−531. HU Jun,YANG Ping. Numerical analysis of temperature field within large–diameter cup–shaped frozen soil wall[J]. Rock and Soil Mechanics,2015,36(2):523−531. [5] 汪永剑,丁仕辉,丘宏余. 软弱富水地层盾构到达端头加固技术[J]. 人民珠江,2017,38(6):61−65. WANG Yongjian,DING Shihui,QIU Hongyu. Technology of reinforcement on weak–water stratum in shield machine receiving end[J]. Pearl River,2017,38(6):61−65. [6] 王升福,樊文虎,戴道文,等. 人工冻结作用下原状软黏土冻融特性试验[J]. 林业工程学报,2020,5(4):154−160. WANG Shengfu,FAN Wenhu,DAI Daowen,et al. Experimental study on freeze–thaw characteristics of undisturbed soft clay under artificial freezing[J]. Journal of Forestry Engineering,2020,5(4):154−160. [7] LIU Yong,HU Jun,XIAO Huawen,et al. Effects of material and drilling uncertainties on artificial ground freezing of cement–admixed soils[J]. Canadian Geotechnical Journal,2017,54(5):1659−1671. [8] 周禹暄,胡俊,林小淇,等. X 型与圆形冻结管单管冻结温度场数值对比分析[J]. 海南大学学报自然科学版,2021,39(2):198−203. ZHOU Yuxuan,HU Jun,LIN Xiaoqi,et al. Numerical comparison and analysis of single pipe freezing temperature field between X–shaped and circular freezing pipe[J]. Natural Science Journal of Hainan University,2021,39(2):198−203. [9] 江汪洋,杨平,陈斌,等. 宁波海相软弱土层人工冻土强度特性试验[J]. 林业工程学报,2017,2(5):126−131. JIANG Wangyang,YANG Ping,CHEN Bin,et al. Experimental study on strength properties of artificial frozen soil in marine soft soil area of Ningbo City,China[J]. Journal of Forestry Engineering,2017,2(5):126−131. [10] 龙伟,荣传新,段寅,等. 拱北隧道管幕冻结法温度场数值计算[J]. 煤田地质与勘探,2020,48(3):160−168. LONG Wei,RONG Chuanxin,DUAN Yin,et al. Numerical calculation of temperature field of freeze–sealing pipe roof method in Gongbei tunnel[J]. Coal Geology & Exploration,2020,48(3):160−168.. doi: 10.3969/j.issn.1001-1986.2020.03.023 [11] 胡向东,李忻轶,吴元昊,等. 拱北隧道管幕冻结法管间冻结封水效果实测研究[J]. 岩土工程学报,2019,41(12):2207−2214. HU Xiangdong,LI Xinyi,WU Yuanhao,et al. Effect of water –proofing in Gongbei tunnel by freeze –sealing pipe roof method with field temperature data[J]. Chinese Journal of Geotechnical Engineering,2019,41(12):2207−2214. [12] 胡向东,洪泽群. 管幕冻结特殊布管形式稳态温度场解析解[J]. 中国公路学报,2018,31(8):113−121. HU Xiangdong,HONG Zequn. Analytical solution to steady−state temperature field of freeze–sealing pipe–roof with specific freezing pipe arrangement[J]. China Journal of Highway and Transport,2018,31(8):113−121.. doi: 10.3969/j.issn.1001-7372.2018.08.012 [13] 吴雨薇,李春芳,胡俊,等. 新型管幕冻结法温度场影响参数分析[J]. 煤田地质与勘探,2019,47(1):155−161. WU Yuwei,LI Chunfang,HU Jun,et al. Analysis of influencing parameters of temperature field in a new pipe–roofing freezing method[J]. Coal Geology & Exploration,2019,47(1):155−161.. doi: 10.3969/j.issn.1001-1986.2019.01.024 [14] 胡俊,欧阳素娟,李春芳,等. 新型管幕冻结法不同冻结管布置方案温度场数值分析[J]. 森林工程,2018,34(3):86−92. HU Jun,OUYANG Sujuan,LI Chunfang,et al. Numerical analysis of development of freezing temperature field in different arrangement of new pipe freezing method[J]. Forest Engineering,2018,34(3):86−92.. doi: 10.3969/j.issn.1006-8023.2018.03.015 [15] 胡俊,刘勇,曾晖. 新型管幕冻结法不同管幕填充形式的温度场数值对比分析[J]. 森林工程,2015,31(6):135−141. HU Jun,LIU Yong,ZENG Hui. Numerical analysis on the temperature field of a new type of pipe –roof freezing method with different fill –in procedures[J]. Forest Engineering,2015,31(6):135−141.. doi: 10.3969/j.issn.1001-005X.2015.06.028 [16] 胡俊,卫宏,曾晖,等. 新型管幕冻结法温度场数值分析[J]. 铁道科学与工程学报,2016,13(6):1165−1172. HU Jun,WEI Hong,ZENG Hui,et al. Numerical analysis of temperature field of new pipe–roof freezing method[J]. Journal of Railway Science and Engineering,2016,13(6):1165−1172.. doi: 10.3969/j.issn.1672-7029.2016.06.023 [17] 杨晓玲,丁文魁,马中华,等. 石羊河流域中下游浅层地温变化及其对气温变化的响应[J]. 土壤学报,2015,52(6):1401−1411. YANG Xiaoling,DING Wenkui,MA Zhonghua,et al. Change in shallow soil temperature and its response to change in air temperature in middle and lower reaches of Shiyang river basin[J]. Acta Pedologica Sinica,2015,52(6):1401−1411. [18] 吴雨薇,胡俊,汪树成. 中空圆环形冻结管单管冻结温度场数值分析[J]. 海南大学学报自然科学版,2018,36(1):41−48. WU Yuwei,HU Jun,WANG Shucheng. Numerical analysis of freezing temperature field with freezing pipes with different geometries[J]. Natural Science Journal of Hainan University,2018,36(1):41−48. [19] 刘静,周文博. 兰州市西新线河堤加固工程设计浅析[J]. 城市道桥与防洪,2016(9):88−90. LIU Jing,ZHOU Wenbo. Elementary analysis on design of river embankment reinforcement project in Xixin line of Lanzhou[J]. Urban Roads Bridges and Flood Control,2016(9):88−90. [20] 师立德,郁万荣,付垒. 变管径冻结管对地铁联络通道冻结温度场的影响分析[J]. 科学技术与工程,2019,19(3):213−220. SHI Lide,YU Wanrong,FU Lei. Influence of variable diameter freezing pipe on freezing temperature field of subway connecting passage[J]. Science Technology and Engineering,2019,19(3):213−220.. doi: 10.3969/j.issn.1671-1815.2019.03.036 [21] ROHSENOW W M, HARTNETT J P, GANTIC E N. 传热学基础手册(上册)[M]. 齐欣译. 北京: 科学出版社, 1992. [22] 苑中显,叶芳,陈峰,等. 人工土壤冻结过程的计算机模拟[J]. 工程热物理学报,2002,21(4):479−482. YUAN Zhongxian,YE Fang,CHEN Feng,et al. Computational simulation to the artificially freezing process of shaft support in Earth[J]. Journal of Engineering Thermophysics,2002,21(4):479−482.. doi: 10.3321/j.issn:0253-231X.2002.04.024 [23] LIU Zhiqiang,LAI Yuanming. Numerical analysis for the ventilated embankment with thermal insulation layer in Qing–Tibetan railway[J]. Cold Regions Science and Technology,2005,42(3):177−184.. doi: 10.1016/j.coldregions.2005.01.003 [24] 张学富,苏新民,赖远明,等. 寒区隧道三维温度场非线性分析[J]. 土木工程学报,2004,37(2):47−53. ZHANG Xuefu,SU Xinmin,LAI Yuanming,et al. Non−linear analysis for three−dimensional temperature fields in cold-region tunnels[J]. China Civil Engineering Journal,2004,37(2):47−53.. doi: 10.3321/j.issn:1000-131X.2004.02.009