乌江渡扩机工程尾水岔洞三维有限元分析

3-D FEM Analysis of Tail Trace Tunnel in Wujiangdu Extension Project in P.R.China

Ansys软件具有强大的前后处理以及可视化功能,能克服复杂岩土工程中的自编程序在该方面的局限性。文章基于Ansys对乌江渡水电站扩机工程的尾水隧洞进行三维建模和后处理,并采用弹塑性程序进行了三维开挖变形稳定计算以及衬砌结构分析,着重研究了不同应力释放比例情况下的隧洞应力和变形以及支护方案,同时考虑了水压力的作用:使得洞周围岩卸荷,部分进入屈服的岩体回到弹性状态。并在前处理中对岔洞采用了子模型技术,使得岔管的变形稳定计算更符合实际情况。最后提出与其他计算机语言相结合的二次开发技术是Ansys软件的发展方向,能更好地满足复杂地下工程的建模和计算。

The limitation of self-programming software may be eliminated by powerful preprocessing- postprocessing and visual function of ANSYS software in complex civil engineering studies. A 3-D excavation deformation calculation and a lining structural analysis for different operation modes were carried out for the Tail Trace Tunnel in Wujiangdu Extension Project in P. R. China. The stress and displacement analysis and the support scheme of tail trace tunnel under different ratios of stress relaxation are processed. The water pressure is taken into consideration at the same time because it creates an unloading condition in the adjacent rock masses and makes the yielded rock elastic. In preprocessing, a sub-model is adopted which gives deformation results in agreement with those in the actual tunnel. Finally, a redevelopment technique combined with other computer languages is brought forward as is trend of ANSYS software development. This technique will satisfy model building and calculation needs for complex underground projects.