Abstract: The deformation law of arch centering is analyzed in the process of pouring arch concrete． A new method is proposed to determine the concrete cast-in-situ section lengths and corresponding formulas based on deformation proportion of arch centering are deduced． When the stiffness of earlier constructed concrete is ignored，all concrete is cast at the same loop，and the deflection of arch centering is a constant． According to influence line of arch centering deflection，a program which is used to calculate the cast length and arch centering deformation is developed by APDL language of ANSYS． This program could automatically calculate every casting length of arch concrete based on the assigned deformation condition． A numerical result shows that deformation proportion caused by each segment of box concrete should be controlled in range of 0． 5 ～ 0． 6，when the arch centering deformation scale is taken as the target．

Key words: reinforced concrete arch rib, casting length, influence line of deflection, cast-in-situ in arch centering, deformation proportion

摘要： 分析了拱圈混凝土浇筑过程中拱架的变形规律，提出了以拱架变形量确定拱圈混凝土浇筑长度的新方法，推导了相应的计算公式，得到了在忽略同一环先期浇筑混凝土刚度影响时，整环混凝土浇筑完成后拱架变形是一个常数的结论。基于拱架挠度影响线，应用 ANSYS 的 APDL 语言编制了拱架现浇钢筋混凝土拱圈浇筑长度和变形计算程序。该程序能根据指定的变形条件，自动计算出每段混凝土的浇筑长度。算例结果表明: 当以拱架变形量为控制目标时，应将每段混凝土浇筑时产生的拱架变形比例控制在 0． 5 ～0． 6 比较合理。

关键词: 钢筋混凝土拱圈, 浇筑长度, 挠度影响线, 拱架现浇, 变形比例