混凝土收缩对空心墩墩顶实体段的应力影响研究

为分析混凝土收缩荷载对空心墩墩顶实体段应力的影响,以某单线铁路空心墩为例,对墩顶实体段进行结构有限元建模分析。分析表明:仅考虑竖向荷载(含动力系数)时,最大拉、压应力出现在顺桥向;考虑混凝土收缩荷载后,最大拉、压应力出现在横桥向,且拉应力数值增加明显,尤其是横桥向拉应力增加2~3倍,混凝土收缩荷载对墩顶实体段应力影响很大,设计配筋时应予以考虑。

Study on Stress Effect of Concrete Shrinkage on Top Solid Section of Hollow Pier

In order to explain the importance of the stress effect of concrete shrinkage on the top solid section of the hollow pier,a single track railway hollow pier is taken for reference and the finite element model is established to analyze the top solid section of the pier. The analysis reveals that the maximum tensile stress and compressive stress appear in the axial direction of the bridge when the vertical load( including the aerodynamic coefficients) is only taken into consideration. The maximum tensile stress and compressive stress appear in lateral direction when the concrete shrinkage load is also considered.Moreover,the tensile stress value increases significantly,and the transverse tension stress increases by about 2 ~ 3 times. Concrete shrinkage load has great influence on the stress at the top solid section of the pier and attention shall be paid to it in the design and calculation of the reinforcement.