岩土力学 ›› 2023, Vol. 44 ›› Issue (7): 1863-1874.doi: 10.16285/j.rsm.2022.1211

• 基础理论与实验研究 •    下一篇

带围压冻融循环下滨海重塑软土力学特性试验研究

张建新1, 2,马昌虎2,郎瑞卿1, 2,孙立强3,杨爱武4,李迪2   

  1. 1. 天津城建大学 天津市软土特性与工程环境重点实验室,天津 300384;2. 天津城建大学 土木工程学院,天津 300384; 3. 天津大学 建筑工程学院,天津 300072;4. 东华大学 环境科学与工程学院,上海 201620
  • 收稿日期:2022-08-05 接受日期:2023-01-08 出版日期:2023-07-17 发布日期:2023-07-16
  • 通讯作者: 郎瑞卿,男,1991年生,博士,副教授,主要从事地基处理等方面的教学与研究。E-mail: tculrq@163.com E-mail:zh-jianxin@126.com
  • 作者简介:张建新,男,1966年生,博士,教授,主要从事城市地下工程方面的教学与研究。
  • 基金资助:
    国家自然科学基金(No.52008286,No.52078336);天津市研究生科研创新项目(No.2021YJSS345)

Experimental study on mechanical properties of coastal remolded soft soil subjected to the freeze-thaw cycle under confining pressure

ZHANG Jian-xin1, 2, MA Chang-hu2, LANG Rui-qing1, 2, SUN Li-qiang3, YANG Ai-wu4, LI Di2   

  1. 1. Key Laboratory of Soft Soil Engineering Character and Engineering Environment of Tianjin, Tianjin Chengjian University, Tianjin 300384, China; 2. School of Civil Engineering, Tianjin Chengjian University, Tianjin 300384, China; 3. School of Civil Engineering, Tianjin University, Tianjin 300372, China; 4. School of Environmental Science and Engineering, Donghua University, Shanghai 201620, China
  • Received:2022-08-05 Accepted:2023-01-08 Online:2023-07-17 Published:2023-07-16
  • Supported by:
    This work was supported by the National Natural Science Foundation of China (52008286, 52078336) and Tianjin Postgraduate Scientific Research Innovation Project (2021YJSS345).

摘要: 滨海软土地区人工冻结工程中土体通常在一定围压下受到冻融作用进而力学性能发生改变,因此开展带围压冻融作用下土体力学特性研究具有重要意义。以天津滨海地区典型淤泥质土为研究对象,通过自主改进的温控应力路径仪,对比分析了常规无围压冻融和带围压冻融下淤泥质土力学特性差异,揭示了冻融围压、冷端温度、冻融循环次数对其超孔隙水压力、应力−应变曲线、强度及变形指标的影响,并通过电镜扫描试验揭示了冻融围压对其力学特性的影响机制。在此基础之上,采用指数函数建立了淤泥质土冻融循环作用下抗剪强度和弹性模量折减系数与上述因素的关系。结果表明:冻融围压降低了冻融后土体内孔隙大小和数量,能够在一定程度上减弱冻融对土体结构的破坏,但对其应力−应变曲线模式影响较小;随着冷端温度的降低和冻融循环次数的增加,冻融后土体强度和模量均大幅度降低;超孔隙水压力随冻融围压和冷端温度的升高及冻融次数的降低而降低。

关键词: 冻融围压, 冻融循环, 应力?应变关系, 冷端温度

Abstract: Mechanical properties of soft soil will change under freeze-thaw cycle with a certain confining pressure in artificial freezing engineering in coastal soft soil area. Therefore, it is of a great significance to study the influence of freeze-thaw cycle under different confining pressures on the mechanical properties of soft soil. This paper takes the typical muddy soil in Tianjin coastal area as the research object. Through a self-improved temperature controlled triaxial apparatus, the differences of mechanical properties of soft soil under conventional freeze-thaw without confining pressure and freeze-thaw with confining pressure are compared and analyzed. Furthermore, the effects of freezing temperature, number of freeze-thaw cycles and freezing-thawing confining pressure on excess pore pressure, stress-strain characteristics, strength and deformation index of soft soil are revealed. The influence mechanism of freeze-thaw confining pressure on the mechanical properties is explored by SEM. Then, the relationship of shear strength, reduction coefficient of elastic modulus of muddy soil and above influence factors is established by using an exponential function. The results show that the freezing and thawing confining pressure reduces the size and number of pores in the soil after freezing and thawing, which can weaken the damage of freezing and thawing to the soil structure to a certain extent. However, the freeze-thaw confining pressure has little effect on the stress-strain curve. With the decrease of freezing temperature and the increase of the number of freeze-thaw cycles, the strength and moduli of soil are greatly reduced. With the increase of freezing-thawing confining pressure, the freezing temperature and the decrease of the number of freeze-thaw cycles, the excess pore pressure decreases.

Key words: freezing-thawing confining pressure, freeze-thaw cycles, stress-strain characteristics, freezing temperature

中图分类号: 

  • TU447
[1] 张锋, 唐康为, 尹思琪, 冯德成, 陈志国, . 冻融粉质黏土的剪切波速与动态回弹模量及其转换关系[J]. 岩土力学, 2023, 44(增刊): 221-233.
[2] 李新明, 张浩扬, 武迪, 郭砚睿, 任克彬, 谈云志, . 石灰−偏高岭土改良遗址土强度劣化特性的冻融循环效应[J]. 岩土力学, 2023, 44(6): 1593-1603.
[3] 张凌凯, 崔子晏, . 干湿−冻融循环条件下膨胀土的压缩及渗透特性变化规律[J]. 岩土力学, 2023, 44(3): 728-740.
[4] 赵顺利, 杨之俊, 傅旭东, 方正, . 考虑应变局部化的粗粒料剪切损伤力学机制[J]. 岩土力学, 2023, 44(1): 31-42.
[5] 魏丽, 柴寿喜, 刘著, 王沛, 李芳, . 以扫描电镜与核磁共振指标评价冻融纤维 加筋土的抗压强度[J]. 岩土力学, 2022, 43(S2): 163-170.
[6] 刘成禹, 郑道哲, 张向向, 陈成海, 曹洋兵, . 冻融温变速率对岩石受载特性的影响规律[J]. 岩土力学, 2022, 43(8): 2071-2082.
[7] 张树明, 蒋关鲁, 叶雄威, 蔡俊峰, 袁胜洋, 罗斌, . 基于破损参数简化的二元介质冻结粉 细砂土本构模型[J]. 岩土力学, 2022, 43(7): 1854-1864.
[8] 魏丽, 柴寿喜, 张琳, 李瑶, . 冻融作用下三类纤维加筋固化土的抗压抗拉性能[J]. 岩土力学, 2022, 43(12): 3241-3248.
[9] 乔趁, 王宇, 宋正阳, 李长洪, 侯志强, . 饱水裂隙花岗岩周期冻胀力演化特性试验研究[J]. 岩土力学, 2021, 42(8): 2141-2150.
[10] 杨爱武, 徐彩丽, 郎瑞卿, 王韬, . 冻融循环作用下城市污泥固化土三维力学 特性及其破坏准则[J]. 岩土力学, 2021, 42(4): 963-975.
[11] 李甜果, 孔令伟, 王俊涛, 王凤华, . 基于核磁共振的季冻区膨胀土三峰孔隙结构演化特征及其力学效应[J]. 岩土力学, 2021, 42(10): 2741-2754.
[12] 张 泽, 马 巍, ROMAN Lidia, MELNIKOV Andrey, 杨 希, 李宏璧. 基于冻融次数−物理时间比拟理论的冻土 长期强度预测方法[J]. 岩土力学, 2021, 42(1): 86-92.
[13] 孙静, 公茂盛, 熊宏强, 甘霖睿, . 冻融循环对粉砂土动力特性影响的试验研究[J]. 岩土力学, 2020, 41(3): 747-754.
[14] 高峰, 曹善鹏, 熊信, 周科平, 朱龙胤, . 冻融循环作用下受荷青砂岩的脆性演化特征[J]. 岩土力学, 2020, 41(2): 445-452.
[15] 张峰瑞, 姜谙男, 杨秀荣, 申发义. 冻融循环下花岗岩剪切蠕变试验与模型研究[J]. 岩土力学, 2020, 41(2): 509-519.
Viewed
Full text


Abstract

Cited

  Shared   
  Discussed   
[1] 姚仰平,侯 伟. 土的基本力学特性及其弹塑性描述[J]. , 2009, 30(10): 2881 -2902 .
[2] 徐金明,羌培,张鹏飞. 粉质黏土图像的纹理特征分析[J]. , 2009, 30(10): 2903 -2907 .
[3] 向天兵,冯夏庭,陈炳瑞,江 权,张传庆. 三向应力状态下单结构面岩石试样破坏机制与真三轴试验研究[J]. , 2009, 30(10): 2908 -2916 .
[4] 石玉玲,门玉明,彭建兵,黄强兵,刘洪佳. 地裂缝对不同结构形式桥梁桥面的破坏试验研究[J]. , 2009, 30(10): 2917 -2922 .
[5] 夏栋舟,何益斌,刘建华. 土-结构动力相互作用体系阻尼及地震反应分析[J]. , 2009, 30(10): 2923 -2928 .
[6] 徐速超,冯夏庭,陈炳瑞. 矽卡岩单轴循环加卸载试验及声发射特性研究[J]. , 2009, 30(10): 2929 -2934 .
[7] 张力霆,齐清兰,魏静,霍倩,周国斌. 淤填黏土固结过程中孔隙比的变化规律[J]. , 2009, 30(10): 2935 -2939 .
[8] 张其一. 复合加载模式下地基失效机制研究[J]. , 2009, 30(10): 2940 -2944 .
[9] 易 俊,姜永东,鲜学福,罗 云,张 瑜. 声场促进煤层气渗流的应力-温度-渗流压力场的流固动态耦合模型[J]. , 2009, 30(10): 2945 -2949 .
[10] 陶干强,杨仕教,任凤玉. 崩落矿岩散粒体流动性能试验研究[J]. , 2009, 30(10): 2950 -2954 .