基于非达西流动的软土非线性固结计算Non-Darcy flow-based calculation of nonlinear consolidation of soft soil
陈智寿,邱国阳,谈华顺,于光明
摘要(Abstract)：
为了研究软土在非达西渗流作用下的非线性固结特性,基于孔隙水质量守恒原理,引入非达西渗流速度方程,建立了以超静孔压为变量同时考虑渗透系数变化的软土地基一维非线性固结方程,采用差分格式离散偏微分方程,获得了超孔隙水压力的数值解答,采用Python进行编程,计算考虑沉积作用的土体非线性固结沉降,并与已有文献结果做了对比,同时分析了非达西渗流参数n和启动压力梯度以及排水条件变化对地基土固结性状的影响。研究结果表明:非达西渗流参数n和启动压力梯度i_c越大,非线性固结完成所需时间就越长,但对固结最终沉降大小没有影响,两个参数对超孔隙水压力消散均有阻塞效应,固结过程对参数n的变化更为敏感。双向排水条件下土体平均固结度最终可达到100%,单向排水条件下土层平均固结度仅达到有限值,固结稳定后其地表沉降小于双向排水计算结果。
关键词(KeyWords)： 固结;非达西流动准则;软土;超孔隙水压力;固结沉降;差分方法
基金项目(Foundation): 国家自然科学基金项目(51878160,51478109,51678145);; 浙江省交通运输厅科研计划项目资助(2017037)
作者(Author): 陈智寿,邱国阳,谈华顺,于光明
DOI: 10.13928/j.cnki.wrahe.2020.S1.020
参考文献(References)：
- [1] TERZAGHI K.Die theorie der hydrodynamischen Spannungerscheinungen und ihr erdbautechnisches anwendungsgebiet [C]// Proc.of the First International Congress:Applied Mechanics,Delft:Applied Mechanics,1924:288- 294.
- [2] HANSBO S.Consolidation of clay with special reference to influence of vertical sand drains [C]//Hansbo:Swedish Geotechnical Institute Pro,Swedish:Inst.Linkoping,1960:1- 160.
- [3] HANSBO S.Consolidation equation valid for both Darcian and non-Darcian flow [J].Geotechnique,2001,51(1):51- 54.
- [4] 谢海澜,武强,赵增敏,等.考虑非达西流的弱透水层固结计算 [J].岩土力学,2007,28(5):1061- 1065.
- [5] 李婉,陈正汉,董志良.考虑地下水浸没作用的固结沉降计算方法 [J].岩土力学,2007,28(10):2173- 2177.
- [6] 李传勋,谢康和.考虑非达西渗流和变荷载影响的软土大变形固结分析 [J].岩土工程学报,2014,37(6):1002- 1009.
- [7] 刘忠玉,闫富有,王喜军.基于非达西渗流的饱和黏土一维流变固结分析 [J].岩石力学与工程学报,2013,32(9):1937- 1944.
- [8] 李刚,张金利,杨庆.非达西渗流与变渗透系数下的大变形固结分析[J].中南大学学报(自然科学版),2016,47(3):977- 983.
- [9] 李刚,张金利,杨庆.基于非线性渗流的大变形固结有限元分析 [J].哈尔滨工程大学学报,2017,38(8):1231- 1237.
- [10] 时刚,刘忠玉,李永辉.循环荷载作用下考虑非达西渗流的软黏土一维流变固结分析 [J].岩土力学,2018,39(S1):521- 528.
- [11] 王素,李传勋,金丹丹.考虑非达西渗流的单层非均质地基固结分析 [J].应用力学学报,2018,35(2):285- 291.
- [12] LAMBE T W,WHITMAN R W.Soil mechanics [M].New York:John Wiley and Sons,1969:553- 554.
- [13] BURLAND J B.On the compressibility and shear strength of natural clays [J].Géotechnique,1990,40(3):329- 378.
- [14] TAVENAS F,JEAN P,LEBLOND P,et al.The permeability of natural soft clays.Part II:Permeability characteristics [J].Canadian Geotechnical Journal,1983,20(4):645- 660.
- [15] SRIDHARAN A,PRAKASH K.Consolidation and permeability behavior of segregated and homogeneous sediments [J].Geotechnical Testing Journal,2001,24(1):109- 120.
- [16] DUBIN B,MOULIN G.Influence of a critical gradient on the consolidation of clays [C]// YONG R N ,F C Townsend:In Consolidation of soils testing and evaluation (STP 892).West Conshohocken:ASTM International,1986:354- 377.
- [17] HANSBO S.Aspects of vertical drain design:Darcian or non-Darcian flow [J].Geotechnique,1997,47(5):983- 992.
- [18] MIKASA,M.The consolidation of soft clay - a new consolidation theory and its application [M].Tokyo:Kajima Institution Publishing Co.,1965:21- 26.
- [19] TAN T,SCOTT R F.Finite strain consolidation:a study of convection [J].Soils and Foundations,1988,28(3):64- 74.
- [20] KIM H J,& MISSION J L C.Development of negative skin friction on single piles:uncoupled analysis based on nonlinear consolidation theory with finite strain and the load-transfer method [J].Canadian Geotechnical Journal,2011,48(6),905- 914.