收稿日期: 2019-01-31
网络出版日期: 2019-09-04
基金资助
国家自然科学基金面上资助项目(41372279)
Compression characteristics and analysis of levee settlement of soft clay in the Yangtze River Estuary
Received date: 2019-01-31
Online published: 2019-09-04
针对长江口地区软土沉降预测困难的问题, 进行了一系列原状软土与重塑软土固结试验, 以研究软土的固结和次固结特性. 探究长江口软土的压缩指数范围、次固结系数与荷载的关系等, 对长江口软土、典型上海软土及崇明岛软土工程特性进行了对比. 采用两种沉降计算方法对工后沉降进行计算及预测, 并分析两种方法的实用性. 试验结果表明: 长江口地区淤泥质粉质黏土压缩指数为0.316$\sim $0.364, 淤泥质黏土为0.267$\sim $0.313, 略大于典型上海软土的压缩指数; 原状土次固结系数随荷载的增大, 先增大后减小, 重塑土次固结系数与荷载无关; 长江口软土次固结系数大于典型上海软土的次固结系数. 长江口软土与典型上海软土及崇明岛区域软土物理性质指标有一定差异.
杨亮, 赵忠义, 秦爱芳 . 长江口软土的压缩特性及围堤沉降预测分析[J]. 上海大学学报(自然科学版), 2019 , 25(4) : 526 -535 . DOI: 10.12066/j.issn.1007-2861.2112
Owing to the difficulty in predicting the settlement of soft clay in the Yangtze River Estuary area, a series of consolidation tests of undisturbed and remoulded soft clays was conducted to study the consolidation and secondary consolidation characteristics of soft clays in this region. The range of compression indexs and the relationship between the coefficient of secondary consolidation in soft clay and the load were investigated. Furthermore, the engineering characteristics of the Yangtze River Estuary soft clay, typical Shanghai soft clay, and Chongming Island soft clay were compared. Two methods were applied to calculate and predict post-construction settlement, and the feasibility of these two methods was analyzed. The compressibility index of muddy silty clay in the Yangtze River Estuary was found to range from 0.316 to 0.364, and that of silty clay ranged from 0.267 to 0.313, which are both somewhat higher than that of typical Shanghai soft clay. With an increase in the load, the secondary consolidation coefficient of undisturbed clay increase at first but decreased afterwards, while the secondary consolidation coefficient of the remoulded clay was independent of the load. The secondary consolidation coefficient of soft clay in the Yangtze River Estuary was found to be greater than that of the typical soft clay in Shanghai. In conclusion, the physical properties of Yangtze River Estuary soft clay, typical Shanghai soft clay, and Chongming Island soft clay are different.
| [1] | 孙更生, 郑大同 . 软土地基与地下工程 [M]. 2 版. 北京: 中国建筑工业出版社, 1984: 18-47. |
| [2] | 周海, 阮伟 . 开发横沙东滩, 建设上海发展新基地的构想[J]. 水运工程, 2012(12):9-13. |
| [3] | 上海岩土工程勘察设计研究院有限公司. 上海市工程建设规范岩土工程勘察规范: DGJ08—37—2012[S]. 上海: 上海岩土工程勘察设计研究院有限公司, 2012. |
| [4] | Mesri G, Godlewski P M . Time- and stress-compressibility interrelationship[J]. Journal of Geotechnical and Geoenvironmental Engineering, 1977,103:106-113. |
| [5] | 武朝军, 叶冠林, 王建华 . 上海浅部土层压缩指数与天然含水率的关系[J]. 岩土力学, 2014,35(11):3184-3190. |
| [6] | Buisman A S K. Results of long duration settlement tests [C]//Proceedings of the First International Conference on Soil Mechanics and Foundation Engineering. 1936: 103-106. |
| [7] | 余湘娟, 殷宗泽, 董卫军 . 荷载对软土次固结影响的试验研究[J]. 岩土工程学报, 2007,29(6):913-916. |
| [8] | 雷华阳, 王学超, 丁小冬 , 等. 软土主次固结划分及影响因素探讨[J]. 工程地质学报, 2014,22(3):489-497. |
| [9] | 孙德安, 申海娥 . 上海软土的流变特性试验研究[J]. 水文地质工程地质, 2010,37(3):74-78. |
| [10] | 周学明, 袁良英, 蔡坚强 , 等. 上海地区软土分布特征及软土地基变形实例浅析[J]. 上海国土资源, 2005,26(4):6-9. |
| [11] | 殷建华 . 从本构模型研究到试验和光纤监测技术研发[J]. 岩土工程学报, 2011,33(1):1-15. |
| [12] | Yin J H . Constitutive modelling of time-dependent stress-strain behaviour of soils[D]. Winnipeg: University of Manitoba, 1990: 314. |
| [13] | Yin J H, Graham J . Viscous elastic plastic modelling of one-dimensional time dependent behaviour of clays[J]. Can Geotech J, 1989,26:199-209. |
| [14] | Yin J H, Graham J . Equivalent times and elastic-visco-plastic modelling of time-dependent stress-strain behaviour of clays[J]. Canadian Geotechnical Journal, 1994,31:42-52. |
| [15] | 姚仰平, 孔令明, 胡晶 . 考虑时间效应的 UH 模型[J]. 中国科学: 技术科学, 2013(3):298-314. |
| [16] | 姚仰平, 祁生钧, 车力文 . 高填方地基工后沉降计算[J]. 水力发电学报, 2016,35(3):1-10. |
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