Abstract: Due to a variety of effects such as surface spalling of segmental end surfaces, uneven coating thickness of epoxied joint, uneven extrusion stress and segmental assembly errors, unequal thickness of epoxied joint appears in the overhanging process of precast segmental girders. The characteristics of the influence of epoxy joint thickness on the shear stiffness and shear bearing capacity of segmental girders has not been yet clear, and the impact of the deck bearing stiffness at the joint location under wheel load also needs to be further investigated. Based on a large-span segmental precast girder bridge, the effect of joint form and epoxy joint thickness on the mechanical properties of precast concrete segmental girders was analyzed by the finite element software ABAQUS. The results show that the shear ultimate load capacity of segmental girders is significantly affected by the form of joints, and the shear bearing capacity of wet joints is apparently higher than that of epoxied joints. The maximum shear stress of 8 mm-thick epoxied joints is about 10% higher than that of 3 mm-thick epoxied joints. The shear bearing capacity of precast segmental girders is influenced to some extent by the thickness of the epoxy joint, but it is higher than the maximum shear force action value of its supporting engineering. The shear stiffness of segmental beams is not significantly affected by the joint forms of wet, dry and epoxied joints.

Key words: bridge engineering; precast concrete segmental beam; prefabrication and assembly; epoxy joint thickness; mechanical properties; finite element analysis

摘要： 受节段端面表层剥落、接缝胶涂装厚度不均匀、挤胶应力不均匀及节段拼装误差等影响，预制节段梁悬拼过程出现不等厚度的接缝胶，胶接缝厚度对节段梁抗剪刚度、抗剪承载力影响特征尚不明确，对车轮荷载作用下接缝位置处桥面承压刚度的影响亦有待深究。笔者依托某大跨节段预制梁桥，基于有限元软件ABAQUS进行了接缝形式、胶接缝厚度对预制混凝土节段梁受力性能的影响分析。结果表明：节段梁抗剪极限承载力受接缝形式影响显著，湿接缝抗剪承载力明显高于胶接缝；8 mm厚胶接缝最大剪应力比3 mm厚胶接缝增大了大约10%；预制节段梁的抗剪承载力受胶接缝厚度一定影响，但均高于其依托工程的最大剪力作用值。节段梁抗剪刚度受湿接、干接、胶接等接缝形式影响不显著。

关键词: 桥梁工程；预应力混凝土节段梁；预制拼装；胶接缝厚度；力学性能；有限元分析