理论与试验研究

不同加卸载路径下灵敏性粉土的变形特性

  • 卢瑞娜 ,
  • 余蓉 ,
  • 高原 ,
  • 石雪英 ,
  • 巩天真
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  • 1.山西大学 电力与建筑学院, 太原 030013;
    2.山西省电力勘测设计院有限公司, 太原 030024;
    3.北京市理化分析测试中心, 北京 100089;
    4.成都建筑材料工业设计研究有限公司, 成都 610000
卢瑞娜(1988—),女,山西河津人,博士,讲师,主要从事地基处理、边坡支护等方面的科研与教学研究。E-mail: luruina@sxu.edu.cn

收稿日期: 2023-08-14

  网络出版日期: 2024-05-09

基金资助

国家自然科学基金(51909204);山西省高等学校科技创新项目(2021L013);山西大学校级大学生创新创业训练计划(X202210108275)

Deformation Property of Sensitivity Silt under Different Loading and Unloading Paths

  • Lu Ruina ,
  • Yu Rong ,
  • Gao Yuan ,
  • Shi Xueying ,
  • Gong Tianzhen
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  • 1. School of Electric Power, Civil Engineer and Architecture, Shanxi University, Taiyuan 0300135, P.R. China;
    2. Shanxi electric power engineering Co.,Ltd., Taiyuan 0300135, P.R. China;
    3. Beijing Center for Physical & Chemical Analysis, Beijing100089;
    4. Chengdu Design & Resesrch Institute of Building Materials Industry Co.,Ltd., Chengdu 6100002, P.R. China

Received date: 2023-08-14

  Online published: 2024-05-09

摘要

山西汾河中游一级阶地的施工中发现,饱和粉土地基受扰动后会产生很大的附加沉降,且迟迟不能稳定,表现出灵敏性。基于一维固结蠕变试验研究不同的加卸载路径对灵敏性粉土变形特性的影响,结果表明:加卸载路径和加卸荷比是影响压缩曲线的重要因素;压缩曲线在出现转折时对应的应力为结构屈服应力;加荷比越大,同级荷载下沉降值、固结系数、次固结系数和主固结比都会增大,同时其压缩曲线越趋近于线性,特征转折点消失,但加荷比越大,可大大减少工期;预压荷载的大小和卸荷比都会影响灵敏性粉土的回弹量,预压荷载大于结构屈服应力时,卸荷比越大,回弹量越大,因此需要采取分级卸载方法减小回弹量,保证预压效果;目标荷载小于结构屈服应力时,超载预压法降低工后沉降效果显著。

本文引用格式

卢瑞娜 , 余蓉 , 高原 , 石雪英 , 巩天真 . 不同加卸载路径下灵敏性粉土的变形特性[J]. 地下空间与工程学报, 2024 , 20(2) : 426 -436 . DOI: 10.20174/j.JUSE.2024.02.09

Abstract

During the construction of the first terrace in the middle reaches of Fenhe River in Shanxi Province, it is found that the saturated silt foundation will have a great additional settlement after being disturbed, and it will not be stable for a long time, showing sensitivity. Based on one-dimensional consolidation creep test, the deformation characteristics of sensitive silt under different loading and unloading paths were studied in this paper. The results show that the loading and unloading path and loading and unloading ratio are important factors affecting the compression curve. The stress corresponding to the turning point of the compression curve is the structural yield stress. The larger the loading ratio is, the larger the settlement, coefficient of consolidation, coefficient of secondary consolidation and primary consolidation ratio under the same loading level increase, and the compression curve becomes more linear and the characteristic turning point disappears, however, the higher the loading ratio, the shorter the construction period. The magnitude of preloading and unloading rate will affect the rebound of sensitive silt. When the preload is greater than the yield stress of the structure, the greater the unloading ratio, the greater the amount of rebound, so it is necessary to take the stepwise unloading method to reduce the amount of rebound to ensure the preloading effect. When the target load is less than the yield stress of the structure, the effect of surcharge preloading method to reduce the post-construction settlement is significant.

参考文献

[1]Delage P. A microstructure approach to the sensitivity and compressibility of some Eastern Canada sensitive clays[J]. Géotechnique, 2010, 60(5): 353-368.
[2]Hanzawa H, Fukaya T, Suzuki K. Evaluation of engineering properties for an ariake clay[J]. Soils and Foundations, 1990, 30(4): 11-24.
[3]肖树芳, 房后国, 王清. 软土中结合水与固结、蠕变行为[J]. 工程地质学报, 2014, 22(4): 531-535.(Xiao Shufang, Fang Houguo, Wang Qing. The bound water, consolidation and creep behavior of soft soil[J]. Journal of Engineering Geology, 2014, 22(4): 531-535. (in Chinese))
[4]龚士良. 上海软黏土微观特性及在土体变形与地面沉降中的作用研究[J].工程地质学报, 2002, 10(4): 378-384.(Gong Shiliang. Study on Micro characteristics of Shanghai soft clay and its role in soil deformation and land subsidence [J]. Journal of Engineering Geology, 2002,10(4): 378-384. (in Chinese))
[5]吴宏伟, 李青, 刘国彬. 上海黏土一维压缩特性的试验研究[J]. 岩土工程学报, 2011, 33(4): 630-636.(Wu Hongwei, Li Qing, Liu Guobin. Characteristics on one-dimensional compressibility of Shanghai clay[J]. Chinese Journal of Geotechnical Engineering, 2011, 33(4): 630-636. (in Chinese))
[6]高彦斌,鲍文鹏,楼康明. 上海地区第4层淤泥质黏土灵敏性试验与分析[J].同济大学学报(自然科学版), 2015, 43(1):140-145. (Gao Yanbin, Bao Wenpeng, Lou Kangming. Laboratory studies on the sensitivity of layer No.4 soft clay in Shanghai[J]. Journal of Tongji University (Natural Science Edition), 2015, 43(1): 140-145. (in Chinese))
[7]缪林昌, 经绯. 江苏海相灵敏性软土特征研究[J]. 岩土力学, 2006, 27(8): 1283-1286.(Miao Linchang, Jing Fei. Study on characteristics of Marine sensitive soft soil in Jiangsu Province [J]. Rock and Soil Mechanics, 2006, 27(8): 1283-1286. (in Chinese))
[8]龙凡, 王立忠, 李凯, 等. 舟山黏土和温州黏土灵敏度差别成因[J]. 浙江大学学报(工学版), 2015, 49(2): 218-224. (Long Fan, Wang Lizhong, Li Kai, et al. Origin of sensitivity difference between Zhoushan clay and Wenzhou clay [J]. Journal of Zhejiang University (Engineering Science Edition), 2015, 49(2): 218-224. (in Chinese))
[9]王立忠, 李玲玲, 丁利,等. 温州煤场软土结构性试验研究[J]. 土木工程学报, 2002, 35(1):88-92. (Wang Lizhong, Li Lingling, Ding Li, et al.Structural test of soft soil in Wenzhou coal yard [J]. China Civil Engineering Journal, 2002, 35(1):88-92. (in Chinese))
[10]王立忠, 丁利, 陈云敏, 等. 结构性软土压缩特性研究[J]. 土木工程学报, 2004, 37(4): 46-53. (Wang Lizhong, Ding Li, Chen Yunmin, et al. Study on compressibility of structured soft soil[J]. China Civil Engineering Journal, 2004, 37(4): 46-53.(in Chinese))
[11]王立忠, 李玲玲. 结构性软土非线弹性模型中泊松比的取值[J]. 水利学报, 2006, 37(2): 150-159.(Wang Lizhong, Li Lingling. The value of Poisson's ratio in non-linear elastic model of structural soft soil [J]. Journal of Hydraulic Engineering, 2006, 37(2): 150-159. (in Chinese))
[12]王立忠, 李玲玲. 结构性土体的施工扰动及其对沉降的影响[J]. 岩土工程学报, 2007, 29(5): 697-704.(Wang Lizhong, Li Lingling. Construction disturbance of structural soil and its effect on settlement [J]. Chinese Journal of Geotechnical Engineering, 2007, 29(5): 697-704. (in Chinese))
[13]洪振舜, 刘松玉, 于小军. 关于结构土屈服破坏的探讨[J]. 岩土力学, 2004, 25(5): 684-687. (Hong Zhenshun, Liu Songyu, Yu Xiaojun. On destructuration of structured soils[J]. Rock and Soil Mechanics, 2004, 25(5): 684-687. (in Chinese))
[14]王军. 结构性软土地基的固结沉降及稳定研究[D]. 杭州:浙江大学, 2002. (Wang Jun. Study on consolidation settlement and stability of structural soft soil foundation [D]. Hangzhou: Zhejiang University. 2002. (in Chinese))
[15]Li C X, Xiao J Y, Wu W B, et al. Analysis of 1D large strain consolidation of structured marine soft clays[J]. Journal of Zhejiang University-Science A, 2020, 21(1):29-43.
[16]陈晓平, 朱鸿鹄, 张芳枝,等. 软土变形时效特性的试验研究[J]. 岩石力学与工程学报, 2005, 24(12): 2142-2148.(Chen Xiaoping, Zhu Honghu, Zhang Fangzhi, et al. Experimental study on deformation and aging characteristics of soft soil [J]. Chinese Journal of Rock Mechanics and Engineering, 2005, 24(12): 2142-2148. (in Chinese))
[17]徐珊, 陈有亮, 赵重兴. 单向压缩状态下上海地区软土的蠕变变形与次固结特性研究[J]. 工程地质学报, 2008, 16(4): 495-501.(Xu Shan, Chen Youliang, Zhao Chongxing. One-dimensional consolidation tests of creep deformation and secondary consolidation characteristics of soft clay in shanghai area[J]. Journal of Engineering Geology, 2008, 16(4): 495-501. (in Chinese))
[18]雷华阳, 丁小冬, 吕乾乾,等. 不同挤压扰动下黏土的次固结特性研究[J]. 岩土力学, 2013, 34(12):3353-3358.(Lei Huayang, Ding Xiaodong, Lü Qianqian, et al. Secondary consolidation characteristics of clay under different extrusion disturbances [J]. Rock and Soil Mechanics, 2013, 34(12): 3533-3358. (in Chinese))
[19]王旭东, 付小敏. 压缩蠕变力学试验的数值模拟研究[J]. 工程地质学报, 2009, 17(4): 533-537.(Wang Xudong, Fu Xiaomin. Numericals simulation test for physical compression creep experiment[J]. Journal of Engineering Geology, 2009, 17(4): 533-537. (in Chinese))
[20]张先伟,王常明,李军霞. 软土固结蠕变特性及机制研究[J]. 岩土力学, 2011, 32(12): 3584-3590.(Zhang Xianwei, Wang Changming, Li Junxia. Research on consolidation creep characteristics and mechanism of soft soil [J]. Rock and Soil Mechanics, 2011, 32(12): 3584-3590. (in Chinese))
[21]孔令荣, 黄宏伟, 张冬梅,等. 2007. 不同固结压力下饱和软黏土孔隙分布试验研究[J].地下空间与工程学报, 2007,3(6):1036-1040.(Kong Lingrong, Huang Hongwei, Zhang Dongmei, et al. 2007. Experimental study on pore distribution of saturated soft clay under different consolidation pressures [J]. Chinese Journal of Underground Space and Engineering, 2007,3(6):1036-1040. (in Chinese))
[22]Gong S L, Li C, Yang S L. The microscopic characteristics of Shanghai soft clay and its effect on soil body deformation and land subsidence[J]. Environmental Geology, 2009, 56(6): 1051-1056.
[23]杨爱武, 张振东, 李潇雯, 等. 考虑前期固结影响的吹填软土安全运营阶段微结构演化特征[J]. 工程地质学报, 2017, 25(2): 284-291.(Yang Aiwu, Zhang Zhendong, Li Xiaowen, et al. Microscopic structure evolution parameters of soft dredger fill in stage of safe operation hyperplasia with preconsolidation effect[J]. Journal of Engineering Geology, 2017, 25(2): 284-291. (in Chinese))
[24]Martin H, Dora C C, Mariano C. Mechanical and physical properties of the montmorillonitic and allophanic clays in the nearsurface sediments of Chalco Valley, Mexico: analysis of contributing factors to land subsidence[A]// Proccedings of the Seventh International Symposium on Land Subsidence Shanghai China[C]. 2005: 23-28.
[25]卢瑞娜, 梁仁旺, 巩天真. 灵敏性粉土的压缩及触变特性研究[J]. 地下空间与工程学报, 2022, 18(1): 227-235. (Lu Ruina, Liang Renwang, Gong Tianzhen. Study on compression and thixotropy properties of sensitive silt [J]. Chinese Journal of Underground Space and Engineering, 2022, 18(1): 227-235. (in Chinese))
[26]柴寿喜, 韩文峰, 王沛, 等. 用冻干法制备微结构测试用土样的试验研究[J]. 煤田地质与勘探, 2005, 33(2): 46-48. (Chai Shouxi, Han Wenfeng, Wang Pei, et al. Experimental study on preparation of microstructural test soil samples by freeze-drying method [J]. Coal Geology and Exploration, 2005, 33(2): 46-48. (in Chinese))
[27]徐学燕. 高等土力学[M]. 哈尔滨: 哈尔滨工业大学出版社, 2008. (Xu Xueyan. Advanced soil mechanics [M]. Harbin: Harbin Institute of Technology Press, 2008. (in Chinese))
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