免疫遗传算法在土石坝筑坝粗粒料本构模型参数反演中的应用研究

建立了确定筑坝粗粒料本构模型参数的有限元计算理论与IGA相结合的反演分析方法，利用公伯峡筑坝现场大型载荷试验资料，对筑坝原级配料的本构模型参数进行了反演研究。结果表明，由于在微弱风化花岗岩掺加云母片岩，颗粒破碎严重，爆破堆石料（3BⅠ）的原级配粗粒料反演参数远低于室内三轴试验成果；与3BⅠ堆石料相反，砂砾料（3BⅡ）现场反演得到的邓肯E~B模型参数高于室内三轴试验值；室内三轴试验成果不能客观反映筑坝材料的力学特性，对于当今的300 m级高土石坝建设，宜加强对原级配粗粒料的力学特性研究；同时对原型实测的空间位移场不同拟合方式进行了探讨，认为仅考虑铅直向变形的IGA参数反演成果能基本满足土石坝工程的精度要求。

Application of immune genetic algorithm to back analysis for parameters in model of rockfill dam coarse grain material

The method of combining the theory of finite element calculation of parameters in model of rockfill dam coarse grain material with the immune genetic algorithm (IGA) is confirmed; and a relevant software is developed. Using the large scale loading test data of Gongboxia dam, constitutive model parameters of rockfill are gained. It is concluded that because the mica schist is mixed with feeble weathered granite, the grain is broken up severely; the back-analysis parameters of explosion rockfill(3BⅠ)are lower than the results of laboratory triaxial test, and the Duncan E-B parameters obtained by back-analysis of her sandy gravel (3BⅡ)are higher than the triaxial test results of laboratory triaxial test which can not reflect the mechanical behaviors of the dam material objectively; the research should be strengthened in 300 m high rockfill dam construction. The fitting modes of the space displacement field of prototype observation are also explored and it turns out that the results of IGA analysis considering only vertical deformation meet the need of dam’s technical accuracy.