冻压条件下冻融软土孔隙特征与动力特性分析

doi:10.13722/j.cnki.jrme.2020.0496

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摘要杭州软土地区地铁联络通道建设多采用冻结法施工，在整个冻结范围内，不同区域的土体冻融期间承受不同冻结温度与冻融压力。通过自主研发土样制作仪器，得到不同组合冻结条件的试样，再基于核磁共振试验，研究冻融土在不同冻结压力、冻结温度以及加载情况下精确孔径分布特征曲线变化规律，并结合动三轴试验深入探究以孔压、应变以及刚度为代表的动力特性。最终，建立以一次对数为基础的动孔压预测模型，该模型参数物理意义清晰，能较好地预测不同冻融条件下软土动孔压发展。研究结果表明：随着冻结温度的降低，孔隙中的水冻胀效果更为明显；冻融期间围压可有效使融土骨架结构更为紧密，从而减少融土在循环荷载下的变形；循环荷载作用下，小孔隙尺寸大幅度减小，尺寸分布范围增大，中等孔隙进一步向次级孔隙发展；不同冻融压力作用下，孔压极限值与冻融完成后中等孔隙的面积呈类线性相关。研究成果可作为冻结法施工条件下，预测冻融土结构损伤程度与循环荷载下孔压发展的可靠依据。

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	孔勃文1
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	丁智3
	何绍衡1
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	庄家煌4

关键词 ：土力学, 人工冻结法施工, 孔径分布, 孔压, 冻融围压, 循环荷载

Abstract：The construction of subway connection channels in Hangzhou is mostly carried out by freezing method，which leads to uneven settlement during operation. In the whole range of frozen soil，the freezing conditions change with the relative relationship between the soil and the freezing pipe. Soil samples frozen under different freezing conditions were obtained using sample making instrument invented by the authors. Nuclear magnetic resonance(NMR) tests were performed to study the variation of pore size distribution curve of freezing-thawing soil under different freezing conditions, and the pore pressure，strain and stiffness of the samples were deeply explored combined with dynamic triaxial test. A concise pore pressure prediction model of soft clay under artificial freezing with clear physical parameters was established. The results show that, with decreasing the freezing temperature，frost-heaving brings about worse destruction of the soil structure. During freezing-thawing period，the confining pressure can effectively compact the framework structure of the soil and reduce the deformation under cyclic loads. The limit value of the pore pressure is linearly correlated with the area of medium pores of pore size distribution curve.

Key words： soil mechanics artificial ground freezing(AGF) pore size distribution pore pressure freezing- thawing confining pressure cyclic loading

引用本文:

孔勃文1，2，丁智3，何绍衡1，2，庄家煌4. 冻压条件下冻融软土孔隙特征与动力特性分析[J]. 岩石力学与工程学报, 2020, 39(11): 2328-2340.
KONG Bowen1，2，DING Zhi3，HE Shaoheng1，2，ZHUANG Jiahuang4. Experimental study on pore features and dynamic behaviors of soft clay under different confine pressures during freezing. , 2020, 39(11): 2328-2340.

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http://rockmech.whrsm.ac.cn/CN/10.13722/j.cnki.jrme.2020.0496 或 http://rockmech.whrsm.ac.cn/CN/Y2020/V39/I11/2328

[13]	叶俊能，陈斌. 海相沉积软土动强度与孔压特性试验研究[J]. 岩土力学，2011，32(增1)：55-60.(YE Junneng，CHEN Bin. Dynamic strength and pore pressure property of marine deposit soft clay[J]. Rock and Soil Mechanics，2011，32(Supp.1)：55-60.(in Chinese))
[36]	章克凌，陶振宇. 饱和黏土在循环荷载作用下的孔压预测[J]. 岩土力学，1994，15(3)：9-17.(ZHANG Keling. The prediction of pore pressure of satyrated clay under cyclic loading[J]. Rock and Soil Mechanics，1994，15(3)：9-17.(in Chinese))
[5]	周科平，李杰林，许玉娟，等. 冻融循环条件下岩石核磁共振特性的试验研究[J]. 岩石力学与工程学报，2012，31(4)：731-737. (ZHOU Keping，LI Jielin，XU Yujuan，et al. Experimental study of nmr characteristics in rock under freezing and thawing cycles[J]. Chinese Journal of Rock Mechanics and Engineering，2012，31(4)：731-737.(in Chinese))
[8]	张立波. 黏性土的微观孔隙结构试验研究[硕士学位论文][D]. 武汉：湖北工业大学，2013.(ZHANG Libo. Experiment study on the micro-pore structure of clay soil[M. S. Thesis][D]. Wuhan：Hubei University of Technology，2013.(in Chinese))
[14]	王元东，唐益群，廖少明，等. 地铁行车荷载下隧道周围加固软黏土孔压特性试验[J]. 吉林大学学报：地球科学版，2011，41(1)：188-194.(WANG Yuandong，TANG Yiqun，LIAO Shaoming，et al. Experimental of pore pressure of reinforced soft clay around tunnel under subway vibrational loading[J]. Journal of Jilin University：Earth Science，2011，41(1)：188-194.(in Chinese))
[16]	郭林，蔡袁强，王军. 长期循环荷载作用下排水条件对饱和软黏土动力特性影响[J]. 岩土力学，2013，34(增2)：94-99.(GUO Lin，CAI Yuanqiang，WANG Jun. Influence of drainage condition on dynamic cyclic behavior of saturated soft clay under long-term cyclic loading[J]. Rock and Soil Mechanics，2013，34(Supp.2)：94-99.(in Chinese))
[23]	葛成. 核磁共振T2谱反演方法研究[硕士学位论文][D]. 大庆：大庆石油学院，2010.(GE Cheng. Study on the method of T2 spectrum inversion from NMR data[M. S. Thesis][D]. Daqing：Daqing Petroleum Institute，2010.(in Chinese))
[25]	韩玉娇，周灿灿，范宜仁，等. 基于孔径组分的核磁共振测井渗透率计算新方法—以中东A油田生物碎屑灰岩储集层为例[J]. 石油勘探与开发，2018，45(1)：170-178.(HAN Yujiao，ZHOU Cancan，FAN Yiren，et al. A new permeability calculation method using nuclear magnetic resonance logging based on pore sizes：A case study of bioclastic limestone reservoirs in the a oilfield of the Mid-East[J]. Petroleum Exploration and Development，2018，45(1)：170-178.(in Chinese))
[32]	王军，丁光亚，潘晓东. 各向异性固结软黏土的循环软化-孔压模型[J]. 哈尔滨工业大学学报，2009，41(12)：166-170.(WANG Jun，DING Guangya，PAN Xiaodong. Cyclic-degradation-pore pressure generation model for anisotropic consolidated clay[J]. Journal of Harbin Institute of Technology，2009，41(12)：166-170.(in Chinese))
[34]	NYAL E W，JOHN R G. Pore pressure and strains after repeated loading of saturated clay[J]. Canadian Geotechnical Journal，2011，12(2)：269-277.
[1]	胡田飞，刘建坤，王青志，等. 冻融循环下粉质黏土不排水剪切性状的试验研究[J]. 中南大学学报：自然科学版，2018，49(6)：1 481-1 490. (HU Tianfei，LIU Jiankun，WANG Qingzhi，et al. Experimental study on undrained strength characteristics of silty clay after freeze-thaw cycling[J]. Journal of Central South University：Science and Technology，2018，49(6)：1 481-1 490.(in Chinese))
[3]	丁智，张孟雅，魏新江，等. 地铁循环荷载下冻融软土孔压发展及微观结构研究[J]. 岩石力学与工程学报，2016，35(11)：2 328-2 336. (DING Zhi，ZHANG Mengya，WEI Xinjiang，et al. Study on pore pressure and microstructure of frozen and thawed soft soil under subway cyclic loading[J]. Chinese Journal of Rock Mechanics and Engineering，2016，35(11)：2 328-2 336.(in Chinese))
[6]	张亚民. 冻融作用下花岗岩的细观损伤机制及演化规律[硕士学位论文][D]. 长沙：中南大学，2012.(ZHANG Yamin. The micro degradation mechanism and evolutionary pattern of granite in condition of freeze-thaw[M. S. Thesis][D]. Changsha：Central South University，2012.(in Chinese))
[9]	肖佃师，卢双舫，陆正元，等. 联合核磁共振和恒速压汞方法测定致密砂岩孔喉结构[J]. 石油勘探与开发，2016，43(6)：961-970. (XIAO Dianshi，LU Shuangfang，LU Zhengyuan，et al. Combining nuclear magnetic resonance and rate-controlled porosimetry to probe the pore-throat structure of tight sandstones[J]. Petroleum Exploration and Development，2016，43(6)：961-970.(in Chinese))
[11]	葛国宝. 考虑施工影响下地铁运营引起的地基土动特性及沉降研究[硕士学位论文][D]. 杭州：浙江大学，2013.(GE Guobao. Research on dynamic characteristics under the condition of shield tunnel construction and subway operation[M. S. Thesis][D]. Hangzhou：Zhejiang University，2013.(in Chinese))
[17]	蒋敏敏，蔡正银，曹培，等. 循环荷载对粉质黏土力学性质的影响[J]. 岩土力学，2009，30(增2)：204-207.(JIANG Minmin，CAI Zhengyin，CAO Pei，et al. Effects of cyclic loading on mechanical properties of slity clay[J]. Rock and Soil Mechanics，2009，30(Supp.2)：204-207.(in Chinese))
[33]	MATASOVICN，VUCETIC M. A pore pressure model for cyclic straining of clay[J]. Soils and Foundations，1992，32(3)：156-173.
[2]	王伟，池旭超，张芳，等. 冻融循环对滨海软土三轴应力-应变曲线软化特性的影响[J]. 岩土工程学报，2013，35(增2)：140-144. (WANG Wei，CHI Xuchao，ZHANG Fang，et al. Effect of freeze-thaw circles on softening behaviors of triaxial stress-strain curve of costal soft soils[J]. Chinese Journal of Geotechnical Engineering，2013，35(Supp.2)：140-144.(in Chinese))
[4]	李杰林，周科平，张亚民，等. 基于核磁共振技术的岩石孔隙结构冻融损伤试验研究[J]. 岩石力学与工程学报，2012，31(6)：1 208- 1 214.(LI Jielin，ZHOU Keping，ZHANG Yamin，et al. Measurement of rock pore structure based on NMR technology[J]. Chinese Journal of Rock Mechanics and Engineering，2012，31(6)：1 208-1 214.(in Chinese))
[7]	田维刚. 多因素耦合作用下岩石冻融损伤机制试验研究[硕士学位论文][D]. 长沙：中南大学，2014.(TIAN Weigang. Experiment study on freezing-thawing damage mechanism of rock under the condition of coupling of multiple factors[M. S. Thesis][D]. Changsha：Central South University，2014.(in Chinese))
[10]	武建胜. 不同剪切应变速率下软黏土力学响应及微观结构分析[硕士学位论文][D]. 广州：广东工业大学，2018.(WU Jiansheng. Analysis of mechanical response and microstructure ofsoft clay under different shear strain rates[M. S. Thesis][D]. Guangzhou：Guangdong University of Technology，2018.(in Chinese))
[12]	周建. 循环荷载作用下饱和软黏土特性研究[博士学位论文][D]. 杭州：浙江大学，1998.(ZHOU Jian. Properties of saturated clay under cyclic loading[Ph. D. Thesis][D]. Hangzhou：Zhjiang University，1998.(in Chinese))
[15]	陈国兴，刘雪珠. 南京粉质黏土与粉砂互层土及粉细砂的振动孔压发展规律研究[J]. 岩土工程学报，2004，26(1)：79-82.(CHEN Guoxing，LIU Xuezhu. Study on dynamic pore water pressure in silty clay interbedded with fine sand of Nanjing[J]. Chinese Journal of Geotechnical Engineering，2004，26(1)：79-82.(in Chinese))
[18]	王冲. 冻融循环作用下土体水热变化特性及滞回机制研究[博士学位论文][D]. 兰州：兰州大学，2018.(WANG Chong. Study of hydro-thermal characteristics and hysteretic mechanisms of soils under freezing and thawing processes[Ph. D. Thesis][D]. Lanzhou：Lanzhou University，2018.(in Chinese))
[27]	DING Z，KONG B W，WEI X J，et al. Laboratory testing to research the micro-structure and dynamic characteristics of frozen-thawed marine soft soil[J]. Journal of Marine Science and Engineering，2019，7(4)：85.
[19]	宾峰. 冻融循环作用下岩石动态力学特性及微观机制研究[硕士学位论文][D]. 长沙：中南大学，2014.(BIN Feng. Study on dynamic mechanical properties and microstructure mechanism of roch under freeze-thaw cycles[M. S. Thesis][D]. Changsha：Zhongnan University，2014.(in Chinese))
[20]	李晋宁. 泥页岩储层孔隙结构表征和连通方式研究[硕士学位论文][D]. 南京：南京大学，2017.(LI Jinning. Study on pore structure characterization and connectivity of shale reservoir[M. S. Thesis][D]. Nanjing：Nanjing University，2017. (in Chinese))
[22]	陈圆. 核磁测井T2谱分布反演算法研究[硕士学位论文][D]. 武汉：华中科技大学，2009.(CHEN Yuan. A dissertation submitted in fulfillment of the requirements for the degree of master of engineering[M. S. Thesis][D]. Wuhan：Huazhong University of Science and Technology，2009.(in Chinese))
[24]	孟平. 核磁共振数据处理软件[硕士学位论文][D]. 武汉：武汉物理与数学研究所，2006.(MENG Ping. NMR data processing software[M. S. Thesis][D]. Wuhan：Wuhan Institute of Physics and Mathematics，2006.(in Chinese))
[26]	KONG B W，YU B Q，XIA T D，et al. Pore size changes in marine soft soil under various freezing conditions[J]. Journal of Marine Science and Engineering，2020，8(3)：170.
[29]	丁智，郑勇，魏新江，等. 不同加载频率及循环应力水平对人工冻融软土动力特性影响试验研究[J]. 铁道学报，2020，42(3)：122-128.(DING Zhi，ZHENG Yong，WEI Xinjiang，et al. Experimental study on the effect of different loading frequency and cyclic stress level for dynamic behaviour of artificial frozen-thawed soft soil[J]. Journal of the China Railway Society，2020，42(3)：122-128.(in Chinese))
[31]	焦贵德，赵淑萍，马巍. 冻融循环后高温冻结粉土在循环荷载下的动力特性试验研究[J]. 土木工程学报，2010，43(12)：107-113. (JAO Guide，ZHAO Shuping，MA Wei. Experimental study of the dynamic characteristics of warm frozen silt after freeze-thaw[J]. China Civil Engineering Journal，2010，43(12)：107-113.(in Chinese))
[35]	唐益群，张曦，赵书凯，等. 地铁振动荷载下隧道周围饱和软黏土的孔压发展模型[J]. 土木工程学报，2007，40(4)：82-86.(TANG Yiqun，ZHANG Xi，ZHAO Shukai，et al. Model of pore water pressure development in saturated soft clay around a subway tunnel under vibration load[J]. China Civil Engineering Journal，2007，40(4)：82-86.(in Chinese))
[21]	高君恒. 基于CPMG和DE脉冲序列核磁共振流体识别方法研究[硕士学位论文][D]. 大庆：大庆石油学院，2010.(GAO Junheng. Study on fluid identification based on NMR CPMG and DE pluse sequence[M. S. Thesis][D]. Daqing：Daqing Petroleum Institute，2010.(in Chinese))
[28]	丁智，张孟雅，魏新江，等. 地铁冻结法工后融土微观结构试验研究[J]. 铁道工程学报，2016，33(11)：106-112.(DING Zhi，ZHANG Mengya，WEI Xinjiang，et al. Experimental research on the microstructure pf tjawed spo；after the subway construction of freezing method[J]. Journal of Railway Engineering Society，2016，33(11)：106-112. (in Chinese))
[30]	丁智，洪其浩，魏新江，等. 地铁列车荷载下人工冻融软土微观试验研究[J]. 浙江大学学报：工学版，2017，51(7)：1 291-1 299. (DING Zhi，HONG Qihao，WEI Xinjiang，et al. Expero，emtal study on micro-structure of artificial freezing and thawing soft sol under subway train load[J]. Journal of Zhejiang University：Engineering Science，2017，51(7)：1 291-1 299.(in Chinese))