断面形式对城市大断面明挖隧道结构内力、施工方案、工程造价等有较大影响，在统计分析我国已建成城市大断面明挖隧道断面形式特点的基础上，对郑州市渠南路隧道工程可能采取的断面形式进行研究，分析直墙平顶、直墙圆顶和直墙折板3种断面形式的受力和断面特点，并采用荷载-结构模型对影响直墙折板隧道断面内力的参数，如折板折起角度、斜板跨度和结构自重等进行研究。结果表明： 渠南路隧道采用直墙折板断面可提高断面利用率，改善结构受力条件，且上述3个参数均会影响直墙折板断面内力计算结果。

The crosssection shape of urban opencut tunnel with large crosssection has a significant effect on the structural internal force, construction scheme and project cost. The crosssection shapes probably used in tunnel on Qunan Road in Zhengzhou are studied based on the statistics and analysis of the crosssection shapes of urban opencut large crosssection tunnel which have been constructed. The characteristics of stress and crosssection of 3 crosssection shapes of straight wall flat plate, straight wall circle plate and straight wall skew plate are analyzed. The parameters, i. e. deflection angle, skew plate span and structural dead weight, which affect the internal force of crosssection in straight wall and skew plate shape, are analyzed by loadstructure model. The study results show that: the utilization rate of crosssection and the structure stressing conditions of tunnel on Qunan Road can be improved by using crosssection in straight wall skew plate shape; and the calculation results of internal force will be affected by deflection angle, skew plate span and structural dead weight.