坝址区覆盖层静力特性参数反演研究

Inversion Study on the Static Characteristic Parameters of Earth Rockfill Dam

采用室内静力三轴剪切试验和现场旁压试验对某土石坝坝基覆盖层的静力特性参数进行了研究。结合参数敏感性分析结果,以室内试验获得的参数为初值,重点研究了采用三维有限元模拟旁压试验的方法对邓肯-张E-B模型参数进行反演分析,并获得各层土体反演参数优化后的曲线。对比现场旁压实测曲线、室内三轴试验曲线和反演参数曲线可知,在室内试验结果的基础上进行反演分析获得的岩土本构模型参数,更能反映土体原位结构性和应力条件等实际情况。

The static characteristic parameters of an earth rockfill dam foundation were studied by using three-axis shear test and field test. Combined with the results of sensitivity analysis and obtained in laboratory tests as the initial parameters, it mainly studied the using three-dimensional finite element simulation of side pressure test method to conduct the inversion analysis of Duncan-Chang E-B model parameters and obtained the optimized curve of inversion parameters of each layer of soil. Compared the results with the field measured near the pressure cun,e, the indoor triaxial test cun,e and the inversion parameter curve show,that in the laboratory experimental results based on inversion analysis of geotechnical constitutive model parameters can better reflect the actual situation of the soil in situ structural and stress conditions.