Experimental study on creep behavior of red clay of existing foundation in Guiyang City
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摘要: 为了准确地掌握喀斯特发育地区岩溶作用对红黏土的结构影响，以及红黏土地基的蠕变特性，以贵州铝厂既有地基红黏土为研究对象，采用分别加载法进行了室内单轴蠕变固结试验和三轴蠕变试验，建立单轴蠕变经验方程以及Singh-Mitchell模型。结果表明：贵州铝厂红黏土的单向固结有线性规律，表现在t/ε和t存在高度的线性相关性，其单向固结经验方程中的一个参数b可用于预测试样在单向固结下的最终沉降量。所建立的Singh-Mitchell三参数的蠕变模型较好表达了试验土体在25%~100%偏应力水平范围内的应力-应变-时间三者的关系特性。同时，SEM图片表明随着竖向压力不断地增大，单轴固结试验下该红黏土的孔隙面积和微观颗粒数减小，颗粒面积变大，三维孔隙率增加，说明能用孔隙变化的微观规律来反映宏观现象。Abstract: In order to further understanding the creep characteristics of red clay in the existing foundation, a uniaxial creep consolidation and triaxial creep tests were carried out in the laboratory respectively, with samples collected from the Guizhou Aluminum Plant, Guiyang City. Then a uniaxial creep empirical equation and Singh-Mitchell model were established based on the test data. The results show that under unidirectional consolidation there is a linear relationship between t/s and t, with a very high correlation coefficient. Because of the high correlation, the parameter b of the uniaxial creep equation can be used to assess total settlement in an uniaxial consolidation condition. The Singh-Mitchell three-parameter creep model established can better express the stress-strain and time relation of tested soil in the range of 25% to 100% deviatoric stress. At the same time, the SEM images show that with the increase of vertical pressure, the pore area and the number of micro particles of the red clay decrease, while the particle area gets larger, and the three-dimensional porosity grows in the uniaxial consolidation test, indicating that the change of the clay particle pores on a micro scale can be used to explain the macro phenomenon.
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[1] 维亚洛夫C C.土力学的流变原理［M］.杜余培,译.北京:科学出版社, 1987:297-342. [2] Zayad Kaddouri ,Olivier Cuisinier ,Farimah Masrouri . Influence of effective stress and temperature on the creep behavior of a saturated compacted clayey soil［J］.Geomechanics for Energy and the Environment,2018. [3] 李良吉. 安宁炼油厂装卸场场坪红黏土强度特性与蠕变变形研究［D］. 湘潭：湘潭大学,2017. [4] 杨爱武,张兆杰,孔令伟.不同应力状态下软黏土蠕变特性试验研究［J］.岩土力学,2014,35(S2):53-60. [5] 唐喜青.洞庭湖地区网纹红土的流变性研究［D］.长沙:中南大学,2010. [6] 李景阳,王朝富,樊廷章.试论碳酸盐岩风化壳与喀斯特成土作用［J］.中国岩溶,1991,10(1):32-41. [7] 廖义玲,朱立军.贵州碳酸盐岩红土［M］.贵阳：贵州人民出版社,2004. [8] 佟婧博.贵州红粘土物理性及部分力学实验的研究［J］.山西建筑,2011,37(8):40-41. [9] 赵蕾,陈筠,郑莆，等.既有红黏土地基压密固结效应研究［J］.科学技术与工程,2016,16(2):229-234,248. [10] GB/T50123-1999,土工试验方法标准［S］.北京:中国计划出版社,1999. [11] 赵龙,甘海啸,唐维,等.陈氏法在TATB基PBX蠕变特性研究中的适用性分析［J］.含能材料,2018,26(7):608-613. [12] 杨爱武,刘琦,闫澍旺,等.结构性吹填软土流变等时曲线研究［J］.煤田地质与勘探,2012,40(6):58-62. [13] 刘业科,邓志斌,曹平,等.软黏土的三轴蠕变试验与修正的Singh-Mitchell蠕变模型［J］.中南大学学报(自然科学版),2012,43(4):1440-1446. [14] Singh A, Mitchell J K.General stress-strain-time function for clay［J］.Journal of the Clay Mechanics and Foundation Division，1968，94（SM1）:21-46. [15] 杨春景,张迪.非饱和重塑黄土三轴蠕变试验研究［J］.长江科学院院报,2016,33(6):75-78. [16] 廖义玲,张竹如,周训华.从岩溶作用认识碳酸盐岩红土的胀缩性［J］.中国岩溶,2000,19(4):342-346. [17] 李景阳,王朝富,樊廷章,等.碳酸盐岩残积红土的结构、构造特征及其成因研究［J］.中国岩溶,1995,14(1):31-39. [18] 陈果,张晨招.基于孔隙特征的黄土微观结构分析［J］.地下水,2013(3):234-235. [19] 李军霞,王常明,张先伟.不同排水条件下软土蠕变特性与微观孔隙变化［J］.岩土力学,2010,31(11):3493-3498. [20] 冯怀平,马德良,刘启塬,等.基于扫描电镜图像的土体三维视孔隙率定量计方法［J］.岩土工程学报,2019,41(3):574-580. [21] 李景阳,朱立军,梁风,等.碳酸盐岩残积红粘土微观结构的扫描电镜研究［J］.中国岩溶,2002,21(4):233-237. [22] 徐日庆,邓祎文,徐波,等.基于SEM图像信息的软土三维孔隙率定量分析［J］.地球科学与环境学报,2015,37(3):104-110. -
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