碱渣土蠕变特性试验及数值模拟研究  

Experimental and numerical simulation studies on creep behavior of soda residue soil

作　　者：元捷衡 王元战[1] 王轩[2] 陈艳萍[2] 龚晓龙 陈通[1] Yuan Jieheng;Wang Yuanzhan;Wang Xuan;Chen Yanping;Gong Xiaolong;Chen Tong(State Key Laboratory of Hydraulic Engineering Simulation and Safety,Tianjin University,Tianjin 300072,China;Tianjin Port(Group)Co.,Ltd.,Tianjin 300461,China)

机构地区：[1]天津大学水利工程仿真与安全国家重点实验室,天津300072 [2]天津港(集团)有限公司,天津300461

出　　处：《土木工程学报》2024年第5期107-116,共10页China Civil Engineering Journal

基　　金：国家自然科学基金(51979191);天津港科技计划(2020-165)。

摘　　要：碱渣土孔隙比大、含水量高、压缩性大,研究其蠕变特性对于准确预测碱渣土地基长期沉降、确保上部结构长期稳定性具有重要意义。以天津港碱渣土为研究对象,采用分级加载-卸载的方式对不同深度处碱渣土进行一维压缩固结试验(包括卸荷回弹与再压缩试验)。通过试样孔隙比随上部固结压力的变化曲线分析了碱渣土的压缩特性;利用“陈氏法”对分级加载过程的应变-时间试验数据进行处理,得到不同深度处碱渣土在不同固结压力下的应变-时间蠕变曲线。在此基础上,根据蠕变曲线衰减稳定规律以及应力-应变等时曲线所反映的非线性蠕变特征,提出采用Merchant元件模型对蠕变试验曲线进行拟合,并确定模型中3个参数的经验计算公式,建立碱渣土非线性蠕变模型。最后,通过编制有限元子程序实现数值开发,将数模计算值与蠕变试验数据、天津港碱渣土地基沉降实测值进行对比,验证所开发数值模型的合理性。Soda residue soil is characterized with large void ratio,high water content and high compressibility.As a result,studying its creep properties is of great significance to accurately predict the long-term settlement of ground of soda residue soil and to ensure the long-term stability of superstructure.One dimensional compression consolidation tests,including unloading rebound and recompression tests,are carried out on soda residue soil of Tianjin Port at different depths by means of step loading and unloading.Compression characteristic of soda residue soil is analyzed by the curves of sample void ratio versus upper consolidation pressure.The creep curves of soda residue soil at different depths under different consolidation pressures are obtained by processing strain-time test data collected during the step loading process with the Chen's method.Based on the decay stability law of creep curves and the nonlinear creep characteristic of stress-strain isochronal curves,the creep test curves are fitted by the Merchant model.Empirical calculation formulas for the three parameters in this model are determined,and then the nonlinear creep model of soda residue soil is established.Finally,numerical simulation is carried out using the developed subroutine of finite element,and the rationality of this numerical model is verified by comparing numerical simulation calculation value with creep test data and the measured value of settlement of soda residue soil ground in Tianjin Port.

关 键 词：碱渣土 蠕变特性 Merchant模型 数值模拟 

分 类 号：TU411[建筑科学—岩土工程]