黑河黏土心墙土石坝分期位移反分析

高心墙土石坝的安全性评价问题涉及到土坝的变形与渗流规律及相关力学参数的确定，是当前土力学研究的热点与难点之一。由于土石坝受施工过程中施工工艺、施工方法和施工质量以及运行期运行环境和管理方法的影响，土石坝坝料的实际力学参数与原设计参数有一定的差别。为获得西安黑河黏土心墙土石坝大坝填料实际的力学参数，利用大坝的应力、变形与渗流观测资料，通过深入分析大坝变形机制和渗流特征，建立了黑河黏土心墙土石坝变形与荷载之间的对应关系，提出了基于准饱和土固结理论的心墙土石坝分期位移反分析的思路与方法，实现了心墙土石坝施工期、运行期全过程反演。结果表明该方法可反演得到心墙土石坝填筑材料的主要参数（邓肯-张模型）、心墙渗透系数及湿化变形参数。反演思路与方法对同类工程设计与反分析具有参考意义。

Back analysis of displacements of Heihe clay core rockfill dam at different stages

The safety evaluation of high earth core rockfill dam through deformation and seepage measurement and analysis is one of most important problem in nowdays soil mechanics at present. Due to the influences of construction method, construction quality and management during and after construction, the real parameters of the dam become quite different from the original designing parameters. So it is of great significance to get real parameters and real running state of the dam based on back analysis in order to evaluate the dam stability exactly and comprehensively. To get the real mechanics parameters of the dam soils, the investigation on stress, deformation and seepage behavior by the in-situ measurement in Heihe clay core rockfill dam in Xi ’an are executed based on analysis of the time property and space property. Then the relationship between the deformation and load is built; and a back analysis method for the soil parameters during construction and operation based on the theory of nearly saturated soils using the 3-D finite element simulation is suggested, from which the DUCAN parameters, seepage coefficients and wetting parameters of the core clay of the dam can be determined directly and realistically. And the method proposed is useful for design and back analysis of these type projects.