城市大断面明挖隧道断面形式研究

Study of Cross-section Shapes of Urban Open-cut Tunnel with Large Cross-section

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 crosssection 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.