预制节段拼装预应力混凝土箱梁胶接缝抗剪性能研究

Shear Behavior of Adhesive Joints of Prefabricated Segmental Assembly Prestressed Concrete Box Girder

由于节段间接缝的影响,导致预制节段预应力混凝土箱梁接缝处抗剪机理与连续整跨梁存在较大差异,在计算抗剪承载力时无法直接应用整跨梁抗剪计算公式。首先对节段拼装箱梁接缝处的抗剪机理进行分析,得到影响计算抗剪承载力的关键参数;其次在已有计算公式的基础上,考虑混凝土立方体抗压强度和接缝处键齿数等参数的影响,提出适用于这种抗剪承载力的计算公式;最后将提出的计算公式与试验数据对比,表明该计算公式中的参数物理意义明确,计算精度较高,为预制节段拼装预应力混凝土箱梁结构的设计及应用提供了一定理论基础。

Due to the influence of segmental indirect joints,there is a large difference between the shear mechanism of continuous span beams and the shear calculation formula of full span beams cannot be directly applied in shear bearing capacity.This paper first analyzes the shear mechanism at the joints of segmented box girder,and obtains the key parameters that affect the calculation of the shear capacity of segmented box girder.Secondly,based on the existing calculation formulas,the compressive strength of concrete cubes is considered.Influence of parameters such as the number of teeth at the joints and other parameters,a calculation formula for the shear capacity of the prestressed concrete box girder with adhesive joints is proposed.Finally,the calculation formula established in this paper is compared with the test data,and the results are compared.It is shown that the parameters in the calculation formula proposed in this paper have clear physical meaning and high calculation accuracy,and provide a certain theoretical basis for the design and application of prestressed concrete box girder structure in the prefabrication stage.