Terzaghi一维固结理论的相似准则和模型试验

Similarity criterion and model test on Terzaghi one-dimensional consolidation theory

为了合理设计和运行一维固结模型试验,根据物理相似原理导出了Terzaghi固结过程中几何、荷载、孔压、时间、固结度等参数的相似常数计算方法。在此基础上,给出了考虑孔隙比、压缩系数、渗透系数随时间变化时,固结系数随应力水平变化的模型试验时间常数修正方法。利用ABAQUS有限元软件分别模拟了原场地和对应模型试验的固结过程,结合室内固结试验成果,应用给出的时间相似算法对数值结果进行了修正。研究表明,不同应力水平对应的固结系数差别较大,采用考虑固结系数变化的时间相似常数计算方法,理论上更加完善,数值上更为准确。研究成果对土工模型试验的设计和运行具有指导意义。

Based on the physical similarity principle,the similarity constants of parameters such as geometry,load,pore pressure,time and consolidation degree in the process of Terzaghi consolida-tion are derived.On this basis,the calculation method of model test time constant considering the change of consolidation coefficient with pressure level is given.The consolidation process of the original site and the corresponding model test were simulated by using ABAQUS finite element software,and the time similarity algorithm was used to modify the numerical results in combination with the indoor consolidation test results.Results show that the consolidation coefficient of different pressure levels varies greatly,while the consolidation degree and pore pressure obtained by the calculation method of time constant of similarity considering the change of consolidation coefficient are more desirable in theory and more accurate in numerical value.The research results of this paper have guiding significance for the design and operation of geotechnical model test.