|
|
|
| Effects of freeze-thaw cycles on mechanical properties of expansive soils at different compaction degrees |
| CHEN Yong1，2，HUANG Yinghao2，WANG Shuo2，CAI Zhengyin2，MU Yanhu3 |
(1. School of Architecture，Tianjin University，Tianjin 300350，China；2. Geotechnical Engineering Department，Nanjing Hydraulic Research Institute，Nanjing，Jiangsu 210024，China；3. State Key Laboratory of Frozen Soil Engineering，
Northwest Institute of Eco-Environment and Resources，Chinese Academy of Sciences，Lanzhou，Gansu 730000，China) |
|
|
|
|
Abstract Freeze-thaw cycles are an important reason for the deterioration of expansive soil mechanical properties in north Xinjiang. In this research，freeze-thaw cycle tests were carried out using a self-designed unidirectional environmental boundary loading device. On this basis，volume measurement，unconfined compressive strength，and scanning electron microscope tests were carried out. The characteristics of volume changes and mechanical properties of expansive soil at three different compaction degrees(90%，95% and 100%) were investigated. The evolution law of mechanical strength deterioration and microscopic pore development was quantitatively analyzed by grey relational analysis. The effect of pore change characteristics on the unconfined compressive strength of soil under freeze-thaw cycles was discussed. The tests results showed that the volume change of specimens gradually changed from shrinkage to swelling with the increased compaction degree. The hardening properties of expansive soils weakened with increasing compaction，and freeze-thaw cycles promoted the softening of stress-strain relationships. The unconfined compressive strength of the specimens was significantly reduced after the first freeze-thaw cycle，with attenuation amplitude from 56.07% to 67.54% after seven cycles. Freeze-thaw cycles also attenuated failure strain and resilient modulus to varying degrees. The correlation between the surface porosity and the unconfined compressive strength attenuation rate was 0.779–0.882，and the corresponding weight reached 0.467–0.471，with an excellent linear relationship. The study results provide a reference for constructing and maintaining expansive soil projects in north Xinjiang.
|
|
|
|
|
|
[1] 谭罗荣，孔令伟. 特殊岩土工程土质学[M]. 北京：科学出版社，2006：2–8.(TAN Luorong，KONG Lingwei. Soil geology for special geotechnical engineering[M]. Beijing：Science Press，2006：2–8.(in Chinese))
[2] 孔令伟，陈正汉. 特殊土与边坡技术发展综述[J]. 土木工程学报，2012，45(5)：141–161.(KONG Lingwei，CHEN Zhenghan. A review of the development of special soil and slope technology[J]. Chinese Journal of Civil Engineering，2012，45(5)：141–161.(in Chinese))
[3] 许 雷，刘斯宏，鲁 洋，等. 冻融循环下膨胀土物理力学特性研究[J]. 岩土力学，2016，37(增2)：167–174.(XU Lei，LIU Sihong，LU Yang，et al. Research on physical and mechanical properties of expansive soil under freeze-thaw cycles[J]. Rock and Soil Mechanics，2016，37(Supp.2)：167–174.(in Chinese))
[4] 朱 锐，蔡正银，黄英豪，等. 冻融过程对高寒区渠道基土力学特性的影响[J]. 农业工程学报，2021，37(14)：108–116.(ZHU Rui，CAI Zhengyin，HUANG Yinghao，et al. Effects of freeze-thaw process on mechanical properties of channel foundation soil in alpine regions[J]. Chinese Journal of Agricultural Engineering，2021，37(14)：108–116.(in Chinese))
[5] TANG L，CONG S Y，GENG L，et al. The effect of freeze-thaw cycling on the mechanical properties of expansive soils[J]. Cold Regions Science and Technology，2018，145：197–207.
[6] 蔡正银，朱 洵，张 晨，等. 高寒区膨胀土渠道边坡性能演变规律[J]. 中南大学学报：自然科学版，2022，53(1)：21–50.(CAI Zhengyin，ZHU Xun，ZHANG Chen，et al. Evolution law of expansive soil channel slope performance in alpine regions[J]. Journal of Central South University：Natural Science，2022，53(1)：21–50.(in Chinese))
[7] 朱 洵，蔡正银，黄英豪，等. 湿干冻融耦合循环作用下膨胀土力学特性及损伤演化规律研究[J]. 岩石力学与工程学报，2019，38(6)：1 233–1 241.(ZHU Xun，CAI Zhengyin，HUANG Yinghao，et al. Study on mechanical properties and damage evolution of expansive soil under the coupled cycle of wet-dry-freeze-thaw[J]. Chinese Journal of Rock Mechanics and Engineering，2019，38(6)：1 233–1 241.(in Chinese))
[8] AL-YAQOUB T H，PAROL J，ZNIDARCIC D. Experimental investigation of volume change behavior of swelling soil[J]. Applied Clay Science，2017，137(3)：22–29.
[9] 蔡正银，朱 洵，黄英豪，等. 冻融过程对膨胀土裂隙演化特征的影响[J]. 岩土力学，2019，40(12)：4 555–4 563.(CAI Zhengyin，ZHU Xun，HUANG Yinghao，et al. Effects of freeze-thaw process on the evolution characteristics of fissures in expansive soils[J]. Rock and Soil Mechanics，2019，40(12)：4 555–4 563.(in Chinese))
[10] WANG M，MENG S，SUN Y，et al. Shear strength of frozen clay under freezing-thawing cycles using triaxial tests[J]. Earthquake Engineering and Engineering Vibration，2018，17：761–769.
[11] VIKLANDER P. Permeability and volume changes in till due to cyclic freeze/thaw[J]. Canadian Geotechnical Journal，1998，35(3)：471–477.
[12] 王铁行，杨 涛，鲁 洁. 干密度及冻融循环对黄土渗透性的各向异性影响[J]. 岩土力学，2016，37(增1)：72–78.(WANG Tiexing，YANG Tao，LU Jie. Anisotropic effects of dry density and freeze-thaw cycles on the permeability of loess[J]. Rock and Soil Mechanics，2016，37(Supp.1)：72–78.(in Chinese))
[13] 胡田飞，刘建坤，房建宏，等. 冻融循环下压实度对粉质黏土力学性质影响的试验研究[J]. 岩石力学与工程学报，2017，36(6)： 1 495–1 503.(HU Tianfei，LIU Jiankun，FANG Jianhong，et al. Experimental study on the effect of compaction on the mechanical properties of silty clay under freeze-thaw cycles[J]. Chinese Journal of Rock Mechanics and Engineering，2017，36(6)：1 495–1 503.(in Chinese))
[14] 中华人民共和国国家标准编写组. GB/T 50123—2019 土工试验方法标准[S]. 北京：中国计划出版社，2019.(The National Standard Compilation Groups of the People?s Republic of China. GB/T 50123—2019 Standard for geotechnical test methods[S]. Beijing：China Planning Press，2019.(in Chinese))
[15] 中华人民共和国国家标准编写组. GB 50112—2013 膨胀土地区建筑技术规范[S]. 北京：中国计划出版社，2013.(The National Standard Compilation Groups of the People?s Republic of China. GB 50112—2013 Technical specification for building in expansive land areas[S]. Beijing：China Planning Press，2013.(in Chinese))
[16] 黄英豪，陈 永，朱 洵，等. 相变材料改良膨胀土冻融特性试验研究及微观机理分析[J]. 岩土工程学报，2021，43(11)：1 994– 2 002.(HUANG Yinghao，CHEN Yong，ZHU Xun，et al. Experimental study and microscopic mechanism analysis of phase change materials for improving the freezing and thawing of expansive soil[J]. Chinese Journal of Geotechnical Engineering，2021，43(11)：1 994–2 002.(in Chinese))
[17] 马 巍，王大雁. 中国冻土力学研究50 a回顾与展望[J]. 岩土工程学报，2012，34(4)：625–640.(MA Wei，WANG Dayan. Review and prospect of frozen soil mechanics research in China in 50 years[J]. Chinese Journal of Geotechnical Engineering，2012，34(4)：625–640.(in Chinese))
[18] 王大雁，马 巍，常小晓，等. 冻融循环作用对青藏黏土物理力学性质的影响[J]. 岩石力学与工程学报，2005，24(23)：4 313–4 319. (WANG Dayan，MA Wei，CHANG Xiaoxiao，et al. Effects of freeze-thaw cycles on physical and mechanical properties of Qinghai-Tibet clay[J]. Chinese Journal of Rock Mechanics and Engineering，2005，24(23)：4 313–4 319.(in Chinese))
[19] 张勇敢，鲁 洋，刘斯宏，等. 冻融循环对掺砾黏土体积变化和力学特性影响的试验研究[J]. 岩石力学与工程学报，2021，40(增2)：3 323–3 333.(ZHANG Yonggan，LU Yang，LIU Sihong，et al. Experimental study on the effect of freeze-thaw cycles on the volume change and mechanical properties of gravel-filled clay[J]. Chinese Journal of Rock Mechanics and Engineering，2021，40(Supp.2)： 3 323–3 333.(in Chinese))
[20] 汪时机，杨振北，李 贤，等. 干湿交替下膨胀土裂隙演化与强度衰减规律试验研究[J]. 农业工程学报，2021，37(5)：113–122. (WANG Shiji，YANG Zhenbei，LI Xian，et al. Experimental study on crack evolution and strength attenuation of expansive soil under alternating dry and wet conditions[J]. Chinese Journal of Agricultural Engineering，2021，37(5)：113–122.(in Chinese))
[21] LU Y，LIU S，ALONSO E，et al. Volume changes and mechanical degradation of a compacted expansive soil under freeze-thaw cycles[J]. Cold Regions Science and Technology，2019，157：206–214.
[22] TIAN L，YU L，LIU S，et al. Deformation research of silty clay under freeze-thaw cycles[J]. KSCE Journal of Civil Engineering，2020，24(2)：435–442.
[23] QI J L，MA W，SONG C. Influence of freeze–thaw on engineering properties of a silty soil[J]. Cold Regions Science and Technology，2008，53：397–404.
[24] 蒋明镜. 现代土力学研究的新视野——宏微观土力学[J]. 岩土工程学报，2019，41(2)：195–254.(JIANG Mingjing. A new vision of modern soil mechanics research-macro and micro soil mechanics[J]. Chinese Journal of Geotechnical Engineering，2019，41(2)：195–254.(in Chinese))
[25] 刘鸿飞，刘俊芳，苏跃宏，等. 无侧限抗压强度异常值处理新方法的研究[J]. 岩土工程学报，2020，42(增1)：137–140.(LIU Hongfei，LIU Junfang，SU Yuehong，et al. Research on a new method for processing outliers of unconfined compressive strength[J]. Chinese Journal of Geotechnical Engineering，2020，42(Supp.1)：137–140.(in Chinese))
[26] LU Y，LIU S，ZHANG Y，et al. Freeze-thaw performance of a cement-treated expansive soil[J]. Cold Regions Science and Technology，2019，170：102926.
[27] LEE W，BOHRA N C，ALTSCHAEFFL A G，et al. Resilient modulus of cohesive soils and the effect of freeze-thaw[J]. Canadian Geotechnical Journal，1995，32(4)：559–568.
[28] JOSEPH W，CHAN K. Product end-of-life options selection：grey relational analysis approach[J]. International Journal of Production Research，2008，46(11)：2 889–2 912. |
|
|
|
2023, Vol. 42 
