PBL剪力键破坏机理及极限承载力影响因素研究  

Study on Failure Mechanism and Influencing Factors of Ultimate Bearing Capacity of PBL Shear Connector

作　　者：陈一馨[1,2] 贾晋三 黄彦轲 刘永生 CHEN Yixin;JIA Jinsan;HUANG Yanke;LIU Yongsheng(Key Laboratory of Road Construction Technology&Equipment,Ministry of Education,Chang’an University,Xi’an 710064,China;Shaanxi Provincial Key Laboratory of Highway Construction Machinery,Chang’an University,Xi’an 710064,China)

机构地区：[1]长安大学道路施工技术与装备教育部重点实验室,西安710064 [2]高速公路施工机械陕西省重点实验室,西安710064

出　　处：《武汉理工大学学报（交通科学与工程版）》2024年第6期1160-1167,共8页Journal of Wuhan University of Technology（Transportation Science & Engineering）

基　　金：陕西省自然科学基础研究计划(2022JQ-576);陕西省交通运输厅项目(21-04X,18-33X)。

摘　　要：文中分别建立了含钢纤维及普通混凝土PBL剪力键有限元模型,混凝土采用损伤塑性的本构模型,钢纤维随机地分布在混凝土基体中.结果表明:钢纤维和普通混凝土PBL剪力键的破坏模式均主要为钢纤维混凝土榫及内部贯通钢筋的剪切破坏以及与钢板平行方向的外包钢纤维混凝土的贯穿裂缝,钢纤维的加入提高了PBL剪力键结构的强度和韧度.利用正交试验的方法,设计了一组包含5因素4水平的钢纤维混凝土PBL剪力键数值试验正交表L 16(45),利用极差分析法讨论了各因素对其钢纤维混凝土PBL剪力键极限承载力的影响,得到最佳配比为:贯穿钢筋直径12 mm,孔洞直径33 mm,钢板厚度10 mm,钢纤维混凝土强度等级C65,钢纤维含量0.5%.结果表明:钢板厚度、钢纤维混凝土强度、贯通钢筋直径、孔洞直径、以及钢纤维含量五个因素均对PBL剪力键极限抗剪承载力有着显著影响.The finite element models of steel fiber reinforced concrete and ordinary concrete PBL shear connectors were established respectively.Concrete adopts the constitutive model of damage plasticity,and steel fibers were randomly distributed in the concrete matrix.The results show that the failure modes of steel fiber reinforced concrete PBL shear key and ordinary concrete PBL shear key are mainly the shear failure of steel fiber reinforced concrete tenon and internal through reinforcement,and the through crack of steel fiber reinforced concrete wrapped parallel to the steel plate.The addition of steel fiber improves the strength and toughness of PBL shear key structure.A set of orthogonal table L 16(45)for numerical test of steel fiber reinforced concrete PBL shear key with 5 factors and 4 levels is designed by orthogonal test method,and the influence of various factors on the ultimate bearing capacity of steel fiber reinforced concrete PBL shear key is discussed by range analysis method.The optimum ratio is:the diameter of the through steel bar is 12 mm,the diameter of the hole is 33 mm,the thickness of the steel plate is 10 mm,the strength grade of steel fiber concrete is C65,and the steel fiber content is 0.5%.The results show that five factors,such as the diameter of through steel bar,the thickness of steel plate,the diameter of hole,the strength of steel fiber concrete and the content of steel fiber,have significant effects on the ultimate shear capacity of PBL shear bond.

关 键 词：PBL剪力键 钢纤维混凝土 极限承载力 数值仿真 正交试验 

分 类 号：U448.34[建筑科学—桥梁与隧道工程]