Full Text:   <970>

Summary:  <243>

Suppl. Mater.: 

CLC number: 

On-line Access: 2022-08-22

Received: 2021-12-28

Revision Accepted: 2022-04-19

Crosschecked: 2022-08-30

Cited: 0

Clicked: 843

Citations:  Bibtex RefMan EndNote GB/T7714

 ORCID:

Yu-hao WU

https://orcid.org/0000-0001-6431-1893

Li-wu FAN

https://orcid.org/0000-0001-8845-5058

-   Go to

Article info.
Open peer comments

Journal of Zhejiang University SCIENCE A 2022 Vol.23 No.8 P.610-620

http://doi.org/10.1631/jzus.A2100673


Effects of moisture content and dry bulk density on the thermal conductivity of compacted backfill soil


Author(s):  Yu-hao WU, Yan-hao FENG, Li-wu FAN, Qing WANG, Xin SONG, Zi-tao YU

Affiliation(s):  Institute of Thermal Science and Power Systems, Zhejiang University, Hangzhou 310027, China; more

Corresponding email(s):   liwufan@zju.edu.cn

Key Words:  Backfill soil, Compaction, Thermal conductivity, Moisture content, Dry bulk density


Yu-hao WU, Yan-hao FENG, Li-wu FAN, Qing WANG, Xin SONG, Zi-tao YU. Effects of moisture content and dry bulk density on the thermal conductivity of compacted backfill soil[J]. Journal of Zhejiang University Science A, 2022, 23(8): 610-620.

@article{title="Effects of moisture content and dry bulk density on the thermal conductivity of compacted backfill soil",
author="Yu-hao WU, Yan-hao FENG, Li-wu FAN, Qing WANG, Xin SONG, Zi-tao YU",
journal="Journal of Zhejiang University Science A",
volume="23",
number="8",
pages="610-620",
year="2022",
publisher="Zhejiang University Press & Springer",
doi="10.1631/jzus.A2100673"
}

%0 Journal Article
%T Effects of moisture content and dry bulk density on the thermal conductivity of compacted backfill soil
%A Yu-hao WU
%A Yan-hao FENG
%A Li-wu FAN
%A Qing WANG
%A Xin SONG
%A Zi-tao YU
%J Journal of Zhejiang University SCIENCE A
%V 23
%N 8
%P 610-620
%@ 1673-565X
%D 2022
%I Zhejiang University Press & Springer
%DOI 10.1631/jzus.A2100673

TY - JOUR
T1 - Effects of moisture content and dry bulk density on the thermal conductivity of compacted backfill soil
A1 - Yu-hao WU
A1 - Yan-hao FENG
A1 - Li-wu FAN
A1 - Qing WANG
A1 - Xin SONG
A1 - Zi-tao YU
J0 - Journal of Zhejiang University Science A
VL - 23
IS - 8
SP - 610
EP - 620
%@ 1673-565X
Y1 - 2022
PB - Zhejiang University Press & Springer
ER -
DOI - 10.1631/jzus.A2100673


Abstract: 
Soil backfilling and compaction are often involved in urban construction projects like the burying of power cables. The thermal conductance of backfill soil is therefore of great interest. To investigate the thermal conductivity variation of compacted backfill soil, 10 typical soils sampled in Zhejiang Province of China with moisture contents of 0%–25% were fully compacted according to the Proctor compaction test method and then subjected to thermal conductivity measurement using the thermal probe method at 20 °C. The particle size distribution and the chemical composition of the soil samples were characterized to analyze their effects on thermal conductivity. The results showed that the maximum thermal conductivity of fully compacted soils generally exceeds 1.9 W/(m·K) and is 20%–50% higher than that of uncompacted soils. With increasing moisture content, soil thermal conductivity and dry bulk density first increase and then remain unchanged or decrease slowly; the critical moisture content is greater than 20% in most cases. Overall, the critical moisture content of soils with large particle size is lower than that of those with small particle size. Quartz has the highest thermal conductivity in the soil solid phase, and the mass percentage of quartz for most soils in this study is more than 50%, while that for yellow soil is less than 30%, which leads to the thermal conductivity of the former being nearly twice as great as that of the latter in most circumstances. Based on regression analysis, with moisture content and dry bulk density as the independent parameters, the prediction formulae for the thermal conductivity of two categories of compacted backfill soils are proposed for practical applications.

含水率和干容积密度对压实回填土热导率的影响

作者:吴宇豪1,冯彦皓1,范利武1,2,王晴3,宋昕3,俞自涛1,2
机构:1浙江大学,热工与动力系统研究所,中国杭州,310027;2浙江大学,能源清洁利用国家重点实验室,中国杭州,310027;3中国科学院,南京土壤研究所,中国南京,210008
目的:本文旨在探究多种物性参数(含水率、干容积密度、粒径分布和化学组成)对充分压实(相对压实度接近100%,绝对压实度大于85%)的回填土热导率的影响规律,并提出便于工程上使用的压实回填土热导率的预测公式。
创新点:通过普氏击实试验(落锤法)使各土壤试样的相对压实度均接近100%,以模拟压实回填土的实际工况,从而使测得的热导率数据和预测模型能够为工程提供可靠的参考。
方法:1.通过实验测试,探究含水率、干容积密度、粒径分布和化学组成于充分压实回填土热导率的影响规律。2.通过回归分析,提出基于质地分类的压实回填土热导率的预测公式。3.预测首先通过相关性分析确定的对土壤热导率影响程度最大的两个参数。
结论:1.压实回填土热导率的最大值比其他文献所报道的自然状态或非压实土壤热导率的最大值大20%~50%。2.与容积干密度类似,压实回填土的热导率随含水率的升高并非一直单调增大;当含水率超过某临界值时,热导率会基本保持不变或缓慢减小,且热导率的峰值点对应的临界含水率一般略大于容积干密度的峰值点对应的临界含水率。3.总体而言,随含水率的升高、干容积密度的增大、粒径的增大、石英含量的升高和有机质含量的降低,压实回填土的热导率均增大,且含水率和干容积密度对热导率的影响较其他因素更显著。4.基于含水率和干容积密度的1/2次方的二元线性回归得到的压实回填土热导率的预测公式具有较高的置信度(各项回归系数的P值均小于0.05)和拟合精度(复相关系数R2大于0.9)。

关键词:回填土;压实;热导率;含水率;干容积密度

Darkslateblue:Affiliate; Royal Blue:Author; Turquoise:Article

Reference

[1]Abu-HamdehNH, ReederRC, 2000. Soil thermal conductivity effects of density, moisture, salt concentration, and organic matter. Soil Science Society of America Journal, 64(4):1285-1290.

[2]Abu-HamdehNH, KhdairAI, ReederRC, 2001. A comparison of two methods used to evaluate thermal conductivity for some soils. International Journal of Heat and Mass Transfer, 44(5):1073-1078.

[3]AlzabeebeeS, 2020. Influence of backfill soil saturation on the structural response of buried pipes. Transportation Infrastructure Geotechnology, 7(2):156-174.

[4]CampbellGS, 1986. Soil physics with basic. Soil Science, 142(6):367-368.

[5]ChungSO, HortonR, 1987. Soil heat and water flow with a partial surface mulch. Water Resources Research, 23(12):2175-2186.

[6]CôtéJ, KonradJM, 2005. A generalized thermal conductivity model for soils and construction materials. Canadian Geotechnical Journal, 42(2):443-458.

[7]CzappS, RatkowskiF, 2021. Optimization of thermal backfill configurations for desired high-voltage power cables ampacity. Energies, 14(5):1452.

[8]DDI (Decagon Devices, Inc.), 2016. KD2 Pro Thermal Properties Analyzer: Operator’s Manual. http://library.metergroup.com/Manuals/13351_KD2%20Pro_Web.pdf

[9]de Lieto VollaroR, FontanaL, VallatiA, 2014. Experimental study of thermal field deriving from an underground electrical power cable buried in non-homogeneous soils. Applied Thermal Engineering, 62(2):390-397.

[10]DuanY, 2015. Experimental Study on Testing and Variation of Soil Thermophysical Parameters. MS Thesis, Taiyuan University of Technology, Taiyuan, China(in Chinese).

[11]GemantA, 1950. The thermal conductivity of soils. Journal of Applied Physics, 21(8):750-752.

[12]HanZ, VanapalliSK, RenJP, et al., 2018. Characterizing cyclic and static moduli and strength of compacted pavement subgrade soils considering moisture variation. Soils and Foundations, 58(5):1187-1199.

[13]HeHL, HeD, JinJM, et al., 2020. Room for improvement: a review and evaluation of 24 soil thermal conductivity parameterization schemes commonly used in land-surface, hydrological, and soil-vegetation-atmosphere transfer models. Earth-Science Reviews, 211:103419.

[14]HiraiwaY, KasubuchiT, 2000. Temperature dependence of thermal conductivity of soil over a wide range of temperature (5–75 °C). European Journal of Soil Science, 51(2):211-218.

[15]HuangCY, XuJM, 2010. Soil Science, 3rd Edition. China Agricultural Press, Beijing, China, p.1-379 (in Chinese).

[16](International Electrotechnical Commission)IEC, 2006. Electric Cables–Calculation of the Current Rating–Part 1-1: Current Rating Equations (100% Load Factor) and Calculation of Losses–General, IEC 60287-1-1:2006. IEC, Geneva, Switzerland.

[17]JohansenO, 1975. Thermal Conductivity of Soils. PhD Thesis, Norwegian University of Science and Technology, Trondheim, Norway.

[18]KimYS, KimJH, ChoDS, 2014. Implementation of optimized backfill materials for underground electric power cables. Journal of Porous Media, 17(9):831-840.

[19]KongDQ, WanR, ChenJX, et al., 2020. Effect of gradation on the thermal conductivities of backfill materials of ground source heat pump based on loess and iron tailings. Applied Thermal Engineering, 180:115814.

[20]LeTHM, LeeTW, SeoJW, et al., 2021. Experimental investigation and numerical analysis on the performance of flowable soil as feasible backfill material for railway bridge approach. Transportation Geotechnics, 28:100542.

[21]LeungMKH, ChanKY, 2009. Theoretical and experimental studies of heat transfer with moving phase-change interface in freezing and thawing of porous potting soil. Journal of Zhejiang University-SCIENCE A, 10(1):1-6.

[22]LuJ, HuangZZ, HanXF, 2005a. Water and heat transport in hilly red soil of southern China: I. Experiment and analysis. Journal of Zhejiang University-SCIENCE B, 6(5):331-337.

[23]LuJ, HuangZZ, HanXF, 2005b. Water and heat transport in hilly red soil of southern China: II. Modeling and simulation. Journal of Zhejiang University-SCIENCE B, 6(5):338-345.

[24]LuS, RenTS, GongYS, et al., 2007. An improved model for predicting soil thermal conductivity from water content at room temperature. Soil Science Society of America Journal, 71(1):8-14.

[25]MaGZ, WeiHL, FuCB, 2000. Relationship between regional soil moisture variation and climatic variability over East China. Acta Meteorologica Sinica, 58(3):278-287 (in Chinese).

[26]MenaceurH, CuisinierO, MasrouriF, et al., 2021. Impact of monotonic and cyclic suction variations on the thermal properties of a stabilized compacted silty soil. Transportation Geotechnics, 28:100515.

[27]MengistuAG, van RensburgLD, MavimbelaSSW, 2017. The effect of soil water and temperature on thermal properties of two soils developed from Aeolian sands in South Africa. CATENA, 158:184-193.

[28]MinJ, 2021. Research on Influencing Factors of Performance of Underground Heat Exchanger of Ground Source Heat Pump. MS Thesis, Anhui Jianzhu University, Hefei, China(in Chinese).

[29]MOHURD (Ministry of Housing and Urban-Rural Development of the People’s Republic of China), 2018. Standard for Design of Cables of Electric Power Engineering, GB 50217-2018. National Standards of the People’s Republic of China(in Chinese).

[30]MOHURD (Ministry of Housing and Urban-Rural Development of the People’s Republic of China), 2019. Standard for Geotechnical Testing Method, GB/T 50123-2019. National Standards of the People’s Republic of China(in Chinese).

[31]NikoosokhanS, NowamoozH, ChazallonC, 2016. Effect of dry density, soil texture and time-spatial variable water content on the soil thermal conductivity. Geomechanics and Geoengineering, 11(2):149-158.

[32]OcłońP, 2021. The effect of soil thermal conductivity and cable ampacity on the thermal performance and material costs of underground transmission line. Energy, 231:120803.

[33]RenXL, YouYH, YuQH, et al., 2021. Determining the thermal conductivity of clay during the freezing process by artificial neural network. Advances in Materials Science and Engineering, 2021:5555565.

[34]RerakM, OcłońP, 2017. The effect of soil and cable backfill thermal conductivity on the temperature distribution in underground cable system. E3S Web of Conferences, 13:02004.

[35]SalataF, NardecchiaF, de Lieto VollaroA, et al., 2015. Underground electric cables a correct evaluation of the soil thermal resistance. Applied Thermal Engineering, 78:268-277.

[36]TangF, LahooriM, NowamoozH, et al., 2021. A numerical study into effects of soil compaction and heat storage on thermal performance of a horizontal ground heat exchanger. Renewable Energy, 172:740-752.

[37]USDA NRCS (United States Department of Agriculture Natural Resources Conservation Service), 2017. Citing Electronic Sources of Information. USDA. https://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/survey/?cid=nrcs142p2_054167

[38]WallenBM, SmitsKM, SakakiT, et al., 2016. Thermal conductivity of binary sand mixtures evaluated through full water content range. Soil Science Society of America Journal, 80(3):592-603.

[39]WebbJ, 1956. Thermal conductivity of soil. Nature, 177(4517):989.

[40]WuHG, YuJH, ShiCZ, et al., 2021. Pipe-soil interaction and sensitivity study of large-diameter buried steel pipes. KSCE Journal of Civil Engineering, 25(3):793-804.

[41]XiaoHL, WuXJ, ZhouJH, 2007. Study on the calculation of thermal conductivity of rock and soil material. Subgrade Engineering, (3):54-56 (in Chinese).

[42]XuL, YuanHM, JiangRF, et al., 2020. Advances in X-ray diffraction for the determination of clay minerals in soil. Spectroscopy and Spectral Analysis, 40(4):‍1227-1231 (in Chinese).

[43]XuXT, ZhangWD, FanCX, et al., 2020. Effects of temperature, dry density and water content on the thermal conductivity of Genhe silty clay. Results in Physics, 16:102830.

[44]YuWJ, 2017. Methods for Estimation of Mean Annual Soil Temperature in China. MS Thesis, Shenyang Agricultural University, Shenyang, China(in Chinese).

[45]ZhangMY, BiJ, ChenWW, et al., 2018. Evaluation of calculation models for the thermal conductivity of soils. International Communications in Heat and Mass Transfer, 94:14-23.

[46]ZhaoC, DongY, FengYP, et al., 2019. Thermal desorption for remediation of contaminated soil: a review. Chemosphere, 221:841-855.

Open peer comments: Debate/Discuss/Question/Opinion

<1>

Please provide your name, email address and a comment





Journal of Zhejiang University-SCIENCE, 38 Zheda Road, Hangzhou 310027, China
Tel: +86-571-87952783; E-mail: cjzhang@zju.edu.cn
Copyright © 2000 - 2024 Journal of Zhejiang University-SCIENCE