吉林大学学报(地球科学版) ›› 2018, Vol. 48 ›› Issue (4): 1165-1173.doi: 10.13278/j.cnki.jjuese.20170075

• 地质工程与环境工程 • 上一篇    下一篇

连云港海相软土不排水强度特征

苟富刚1,2, 龚绪龙1,2, 王光亚1,2   

  1. 1. 江苏省地质调查研究院, 南京 210049;
    2. 国土资源部地裂缝地质灾害重点试验室, 南京 210049
  • 收稿日期:2017-12-03 出版日期:2018-07-26 发布日期:2018-07-26
  • 作者简介:苟富刚(1985-),男,工程师,主要从事特殊土体和环境地质方面的研究工作,E-mail:gfggfg@foxmail.com
  • 基金资助:
    中国地质调查局项目(1212011220005);江苏沿海地区综合地质调查项目(20120223);连云港城市地质调查项目(20170821)

Shear Strength and Failure Characteristics of Marine Soft Soil in Lianyungang

Gou Fugang1,2, Gong Xulong1,2, Wang Guangya1,2   

  1. 1. Geological Survey of Jiangsu Province, Nanjing 210049, China;
    2. Key Laboratory of Earth Fissures Geological Disaster Ministry of Land and Resources, Nanjing 210049, China
  • Received:2017-12-03 Online:2018-07-26 Published:2018-07-26
  • Supported by:
    Supported by Project of China Geological Survey (1212011220005), Comprehensive Geological Survey Project in Jiangsu Coastal Area (20120223) and Lianyungang Urban Geological Survey Project(20170821)

摘要: 连云港地区软土为碱性环境下沉积的非均质海积软土,软土抗剪强度具有固有各向异性。采用三轴不固结不排水剪切(UU)试验、无侧限抗压强度(UTC)试验、快剪试验和原位十字板剪切(FVT)试验4种方法,对连云港地区软土的不固结不排水抗剪强度特征进行了研究。结果表明:土体水平剪切面强度最低,竖直面抗剪强度最高;土体制样采用垂直方向的切取试样方式时,土体强度最高。根据三轴UU试验得出的黏聚强度和内摩擦角基于土体单元极限平衡理论恢复了土体剪切破坏时的应力状态,计算出土体实际抗剪强度。三轴UU试验得出的抗剪强度平均值约为13.13 kPa,试样破裂面与水平面的夹角在45.1°~45.7°区间最为集中。UTC试验测得的土体平均抗剪强度近似等于三轴UU试验测得的平均抗剪强度。FVT试验测得软土抗剪强度平均值为19.72 kPa,与三轴UU试验和UTC试验得出的抗剪强度平均值相比高了约6.60 kPa,这种现象与室内试验试样的机械扰动、土体应力状态改变和剪切面特征有关。

关键词: 抗剪强度, 三轴不固结不排水试验, 无侧限抗压强度试验, 原位十字板试验, 相关性

Abstract: The soft soil in Lianyungang is a heterogeneous marine soft soil deposited in an alkaline environment, its shear strength is inherently anisotropic. We studied the unconsolidated undrained shear strength of soft soil by tri-axial UU test, UTC test, Fast shear test, and FVT test. The results indicate that the horizontal plane shear strength is the lowest; while the vertical plane shear strength is the highest. Using the cohesion and friction angle obtained by the three axis UU test, we restored the stress of soil shear failure state based on the soil unit limit equilibrium theory, and calculated the actual shear strength of soil. The average shear soil strength of the tri-axial UU test is 13.13 kPa. The angle between the sample fracture surface and the horizontal plane is most concentrated in the range of 45.1°-45.7°. The average strength of the UTC test approximately equates that of the three axis UU test. The average soft soil strength by the conventional FVT test is 19.72 kPa, nearly 6.60 kPa higher than that by the other two tests. This phenomenon is related to the mechanical disturbance of the lab test samples, the change of the stress state of the soil, and the characteristics of shear plane.

Key words: shear strength, tri-axial unconsolidation and undrained test, unconfined compression test, field vane shear test, correlation

中图分类号: 

  • P642
[1] 武心婷, 聂正西,范礼彬, 等.临海高等级公路软黏土分布及成因[J]. 路基工程, 2012(6):66-69. Wu Xinting, Nie Zhengxi, Fan Libin, et al. Distribution and Genesis of Soft Clay Along High-Class Coastal Expressway[J]. Subgrade Engineering, 2012(6):66-69.
[2] 吴玉辉, 侯晋芳, 闫澍旺. 软土地基稳定性计算中抗剪强度指标的相关分析[J]. 水利学报, 2011(1):76-81. Wu Yuhui, Hou Jinfang, Yan Shuwang. Analysis of Shear Strength Parameters in Soft Clay Ground Stability Calculation[J]. Shuili Xuebao, 2011(1):76-81.
[3] Leroueil S,La Rochelle P. Remarks on the Stability of Temporary Cuts[J]. Canadian Geotechnical Journal, 1990, 27:687-692.
[4] 王常明, 黄超, 张浩, 等. 营口软土的固结不排水剪切蠕变特性[J]. 吉林大学学报(地球科学版), 2009, 39(4):728-733. Wang Changming, Huang Chao, Zhang Hao, et al. Creep Characteristics for Consolidated-Undrained Triaxial Compression of Yingkou Soft Soil[J]. Journal of Jilin University (Earth Science Edition), 2009, 39(4):728-733.
[5] 《工程地质手册》编委会. 工程地质手册[M]. 5版. 北京:中国建筑工业出版社, 2018. 《Manual of Engineering Geology》 Editorial Board. Manual of Engineering Geology[M]. 5th ed. Beijing:China Architecture and Building Press, 2018.
[6] 岩土工程勘察规范GB50021-2001[S]. 北京:中国建筑工业出版社, 2009. Code for Investigation of Geotechnical Engineering GB50021-2001[S]. Beijing:China Architecture and Building Press, 2009.
[7] 土工试验方法标准GB/T50123-1999[S]. 北京:中国建筑工业出版社,1999. Standard for Soil Test Method GB/T50123-1999[S]. Beijing:China Architecture and Building Press, 1999.
[8] 软土地区岩土工程勘察规程JGJ83-2011[S].中国建筑工业出版社, 2011. Specification for Geotechnical Investigation in Soft Clay Area JGJ83-2011[S]. China Architecture and Building Press, 2011.
[9] 罗传庆, 张吾渝,李辉, 等. 西宁地区原状黄土强度各向异性试验研究[J]. 工程地质学报, 2016, 24(6):1327-1332. Luo Chuanqing, Zhang Wuyu, Li Hui,et al. Experimental Study on the Anisotropic Strength of Intact Loess in Xining[J]. Journal of Engineering Geology, 2016, 24(6):1327-1332.
[10] 洪昌华, 龚晓南.不排水强度的空间变异性及单桩承载力可靠性分析[J].土木工程学报, 2000, 33(3):66-70. Hong Changhua, Gong Xiaonan. Spatial Variability of Undrained Strength and Reliability Analysis of Single Pile[J]. China Civil Engineering Journal, 2000, 33(3):66-70.
[11] 高彦斌,楼康明. 上海软黏土强度固有各向异性[J]. 同济大学学报(自然科学版), 2013, 41(11):1658-1664. Gao Yanbin, Lou Kangming. Strength Anisotropy of Shanghai Soft Clay Induced by Inherent Fabric[J]. Journal of Tongji University (Natural Science), 2013,41(11):1658-1664.
[12] Mitchell J K, Soga K. Fundamentals of Soil Funda-mentals of Soil Behavior[M].New York:John Wiley& Sons, 2005.
[13] 袁聚云, 杨熙章, 赵锡宏, 等. 上海软土各向异性性状的试验研究[J]. 水电自动化与大坝监测, 1996, 20(2):10-14. Yuan Juyun, Yang Xizhang, Zhao Xihong, et al. Experimental Study on Anisotropic Characteristic of Shanghai Soft Clay[J]. Hydropower Automation and Dam Monitoring, 1996, 20(2):10-14.
[14] 吴燕开, 刘松玉, 洪振舜. 土层工程性质与其沉积环境关系分析研究[J]. 工程地质学报, 2004, 12(3):263-268. Wu Yankai, Liu Songyu, Hong Zhenshun. The Relationship Between the Geotechnical Properties and the Deposited Environment for the Soil[J]. Journal of Engineering Geology, 2004, 12(3):263-268.
[15] 邓永锋, 吴燕开, 刘松玉, 等. 连云港浅层海相软土沉积环境及物理力学性质研究[J]. 工程地质学报, 2005, 13(1):29-34. Deng Yongfeng, Wu Yankai, Liu Songyu, et al. Sediment Environment of Shallow Marine Clays Deposited in Lianyungang Area and Their Physical and Mechanical Properties[J]. Journal of Engineering Geology, 2005, 13(1):29-34.
[16] 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. Features Research of Jiangsu Marine Sensitive Soft Soils[J]. Rock and Soil Mechanics, 2006, 27(8):1283-1286.
[17] 黄高峰, 王瑞瑞. 连云港软土不排水抗剪强度与锥尖阻力相关性分析[J]. 勘察科学技术, 2015(4):31-38. Huang Gaofeng, Wang Ruirui. Correlation Analysis Between Undrainage Shear Strength and Cone Point Resistance of Lianyungang Soft Soil[J]. Site Invest Sci Technol, 2015(4):31-38.
[18] Tanaka Hiroyuki, Hirabayashi Hiroshi, Matsuoka Tatsuya, et al. Use of Fall Cone Test as Measurement of Shear Strength for Soft Clay Materials[J]. Soils and Foundations, 2012, 52(4):590-599.
[19] 邵允铖.受扰动土性状室内试验研究[D].杭州:浙江大学, 2008. Shao Yuncheng. Study on Laboratory Test of Properties of Disturbed Soil[D].Hangzhou:Zhejiang University, 2008.
[20] 周晖. 矿物成分对软土强度性质的影响分析[J]. 工业建筑, 2013, 43(7):61-64. Zhou Hui. Analysisof Mineral Composition Impact on Soft Soil's Strength Properties[J]. Industrial Construction, 2013, 43(7):61-64.
[21] 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. Cause of Sensitivity Difference of Zhoushan Clay and Wenzhou Clay[J]. Journal of Zhejiang University (Engineering Science), 2015, 49(2):218-224.
[22] 雷华阳, 肖树芳. 软土结构性的试验研究及其对工程特性的影响[J]. 吉林大学学报(地球科学版), 2004, 34(1):106-110. Lei Huayang, Xiao Shufang. Experimental Study on Soft Soil Structural Property and Its Influences on Engineering Characteristics[J]. Journal of Jilin University (Earth Science Edition), 2004, 34(1):106-110.
[1] 洪勇, 车效文, 郑孝玉, 刘鹏, 周蓉. 陕西泾阳南塬滑坡干湿黄土快速大剪切力学特性[J]. 吉林大学学报(地球科学版), 2017, 47(4): 1207-1218.
[2] 高平,张延军,方静涛,张庆,李宏伟. 浅层岩土室内、外热物性测试的相关性[J]. 吉林大学学报(地球科学版), 2014, 44(1): 259-267.
[3] 万丽,邓小成,王庆飞,刘欢. 基于Hurst指数的矿化强度识别-以山东大尹格庄金矿为例[J]. 吉林大学学报(地球科学版), 2013, 43(1): 87-92.
[4] 王常明, 马栋和, 林容, 王科, 宋朋燃. 辽西地区黄土的强度与本构特性[J]. J4, 2010, 40(5): 1104-1109.
[5] 张艳彬,王 玉,杨忠芳,陈岳龙. 成都经济区土壤磁化率特征及其环境意义[J]. J4, 2007, 37(3): 597-0604.
[6] 贾大成,邢立新, 潘 军, M. J. van Bergen, H. van Roermund. 伊通上地幔剪切带捕虏体中富铝尖晶石的地球化学特征[J]. J4, 2006, 36(04): 497-502.
[7] 张 延 军. 边坡渗流耦合变形分析方法的研究及其应用[J]. J4, 2006, 36(01): 103-0107.
Viewed
Full text


Abstract

Cited

  Shared   
  Discussed   
[1] 宋明春, 李杰, 李世勇, 丁正江, 谭现锋, 张照录, 王世进. 鲁东晚中生代热隆-伸展构造及其动力学背景[J]. 吉林大学学报(地球科学版), 2018, 48(4): 941 -964 .