考虑渗透系数随时间变化及固结状态影响的一维固结计算  

One dimensional consolidation calculation considering the change of permeability coefficient with time and the influence of consolidation state

作　　者：金超奇 徐长节[1] 江平 颜建伟 程超 章立辰 JIN Chaoqi;XU Changjie;JIANG Ping;YAN Jianwei;CHENG Chao;ZHANG Lichen(Jiangxi Key Laboratory of Infrastructure Safety Control in Geotechnical Engineering, National Experimental Teaching Demonstration Center of Civil Engineering, East China Jiaotong University, Nanchang 330013, P. R. China;Jiangxi Provincial Port & Waterway Construction Inverstment Group Co., Ltd, Nanchang 330008, P. R. China)

机构地区：[1]华东交通大学江西省岩土工程基础设施安全与控制重点实验室,土木工程国家实验教学示范研究所,南昌330013 [2]江西省港航建设投资集团港航运输有限公司,南昌330008

出　　处：《土木与环境工程学报（中英文）》2022年第5期157-164,共8页Journal of Civil and Environmental Engineering

基　　金：国家杰出青年科学基金(51725802);国家自然科学基金-高铁联合基金(U1934208);江西省自然科学基金(20192ACB20001);江西省交通运输厅重点工程科技项目(2019C0010、2019C0011)。

摘　　要：固结系数的不确定性是传统固结理论计算局限性的根本原因,传统固结理论计算忽略了在固结过程中渗透系数k和孔隙比e随固结状态和时间的变化。基于工程常用的5种渗透系数预测模型,结合固结度与侧限压缩量的关系,推导出孔隙比e_(t)的时间函数,构建渗透系数与时间及固结应力依赖的计算公式。将构建的渗透系数计算式代入固结系数C_(v)中,同时考虑固结状态、固结应力及时间的影响,对经典Terzaghi一维固结理论进行修正。利用已有的试验数据进行对比,讨论预测公式的适用性。最后通过工程案例计算,与Terzaghi一维固结方程和其他修正固结理论对比,结果表明:当上覆荷载较大时,需要考虑固结系数C_(v)的变化;同时,对比其他修正固结理论,证明了考虑孔隙比e和渗流系数k随时间变化过程的必要性。The uncertainty of the consolidation coefficient is the fundamental reason for the limitation of the traditional consolidation theoretical calculation,which ignores the variation of permeability coefficient k and porosity ratio e with the consolidation state and time during the consolidation.In this paper,the porosity time-history is derived on the basis of five commonly used prediction models of permeability coefficient in engineering,having the relationship between consolidation degree and confined compression.Thus,the calculation formula of permeability coefficient related to both time and consolidation stress is constructed.Here the one-dimensional consolidation theory is modified by substituting the permeability coefficient formula into the consolidation coefficient C_(v) and considering the consolidation state as well as consolidation stress and time variation.The comparations with the literatures and engineering cases confirm the necessity of the time effect on the porosity.The change of consolidation coefficient C_(v) cannot be ignored when suffering a larger overlying load.At the same time,it is proved that it is necessary to consider the process of porosity ratio e and seepage coefficient k changing with time by comparing with other modified consolidation theories.

关 键 词：渗透系数 孔隙比 固结状态 固结应力 时间依赖 

分 类 号：TU431[建筑科学—岩土工程]