关键词: 隧道洞门, 简化计算方法, 正削式洞门, 结构计算

Abstract: The bamboo-truncating tunnel portal’s structure is at complicated 3D stress condition, so 3D numerical calculation method is necessary to used for correct result relatively. For the simplifying calculation model, the trial was carried out for up bamboo-truncating tunnel portal which with the slope 1: 1.5 in Class Ⅴ surrounding rock. Firstly, the model test result was used to proof the arch crown surrounding rock stress which gained by 3D numerical analysis, both have good compatibility. Secondly proceed from the structural stress character and the distribution of surrounding rock stress, the inner force controlling cross-section of structural transverse and longitudinal direction were gained. Through the research, the relationship between q and of arch crown load in each pressure distribution figure was also obtained. Furthermore, the pressure distribution graphics in transverse direction was plotted; and load value calculation methods in longitudinal direction was provided. Therefore, the calculation model was simplified from 3D numerical structural calculation to load-structure model with transverse and longitudinal direction to calculate its inner force separately.

Key words: tunnel portal, simplified calculation method, up bamboo-truncating tunnel portal, structural calculation