钢锚箱栓钉剪力连接件群钉效应及抗剪承载力计算方法  

Group Studs Effect and Shear Strength Calculation Method for Group Studs Shear Connector of Steel Anchor Box

作　　者：周绪红[1,2] 逯文茹[1] 狄谨[1,2] 秦凤江[1] 赵敏[1] 

机构地区：[1]长安大学公路学院,陕西西安710064 [2]重庆大学土木工程学院,重庆400044

出　　处：《中国公路学报》2014年第12期33-45,共13页China Journal of Highway and Transport

基　　金：国家自然科学基金项目(51378069)

摘　　要：为了深入研究钢锚箱栓钉群钉剪力连接件的受力特性,对其群钉效应及主要影响因素进行了有限元分析,进而考虑由群钉效应所引起的单钉平均抗剪承载力降低现象,给出了计入承载力折减系数的群钉连接件抗剪承载力计算公式。研究结果表明:群钉效应将导致栓钉连接件单钉平均抗剪承载力和抗剪刚度显著降低及栓钉传力不均匀现象,同时也将造成栓钉轴向应力的变化,但对栓钉剪应力和弯曲应力水平及其分布形式无明显影响;随着栓钉层数的增加,栓钉单钉平均抗剪承载力及抗剪刚度逐渐减小;当栓钉层间距由2.3倍栓钉直径增加至13.6倍栓钉直径时,栓钉单钉平均抗剪承载力先增大后减小,单钉平均抗剪刚度逐渐降低;当连接件的破坏形态为栓钉的弯剪破坏时,混凝土强度等级的提高对群钉连接件抗剪承载力影响较小,但可提高其抗剪刚度;提出的栓钉群钉连接件抗剪承载力计算公式可为钢锚箱栓钉群的合理布置提供理论依据。For further study of mechanical characteristics of group studs shear connector, finite element analysis was carried out to study the group studs effect and its influence factors. Then, with the reduction coefficient of bearing capacity introduced, a shear strength calculation formula for group studs shear connector was proposed with consideration of the average shear strength decrease of single stud. The results show that the group studs effect sharply reduces the average shear strength and shear stiffness of single stud, makes the load-transferring to be inhomogeneous, and causes the change of axial stress for studs, but has no significant impact on the shear stress, bending stress, and their distributions along the stud. With the increase of the number of stud layers, the average shear strength and shear stiffness of single stud decrease gradually. When the space between the stud layers is increased from 2.3 to 13. 6 times of the diameter of the stud, the average shear strength of single stud increases first and then decreases, and the average shear stiffness decreases gradually. When the failure pattern of the connector is stud bending and shearing failure, with the increase of concrete strength grade, the shear strength of the group studs connector has little change, but the shear stiffness of the studs can be increased obviously. The proposed shear strength calculation formula for group studs shear connector can provide a theoretical basis for reasonable setting of studs groups for steel anchor bOX.

关 键 词：桥梁工程 栓钉群钉剪力连接件 有限元分析 群钉效应 抗剪承载力 抗剪刚度 

分 类 号：U443.38[建筑科学—桥梁与隧道工程]