配置PBL剪力键钢-UHPC组合桥面板纵向受拉性能的试验及分析

Test and Analysis of Longitudinal Tensile Performance of Steel-UHPC Composite Bridge Deck with PBL Shear Connector

为明确剪力键类型对钢-超高性能混凝土(Ultra High Performance Concrete,UHPC)组合桥面板负弯矩区纵向受力性能的影响,设计制作了2个钢-UHPC组合桥面板局部足尺模型试件并对其进行了受拉静载试验。利用有限元软件ABAQUS对受拉试验进行有限元分析,用经试验验证的有限元模型,探讨了开孔钢板厚度、PBL剪力键数量和配筋率对组合板纵向受力性能的影响。结果表明:采用PBL键的组合板钢,UHPC层之间无明显滑移;相比配置栓钉的组合板试件,配置PBL剪力键的组合板试件抗裂性能略有提高,但试件开裂后的刚度显著提升,初裂强度提高3.6%,裂缝宽度0.05 mm时的名义抗拉强度增加了3.3%,开裂后的刚度可提高52.7%;钢-UHPC组合桥面板纵向受力性能主要受配筋率的影响,PBL剪力键间距和开孔钢板厚度的影响较小。

In order to clarify the influence of shear connector types on the longitudinal mechanical behavior of steel-UHPC composite bridge decks in the negative moment zone,two local full-scale model specimens of steel-UHPC composite bridge decks were designed and fabricated and subjected to tensile static load tests.Using finite element software ABAQUS,the numerical analysis of the tensile test was carried out,and the finite element model verified by the experiment was used to discuss the effects of the thickness of the perforated steel plate,the number of PBL shear connectors and the ratio of reinforcement on the longitudinal mechanical properties of the composite deck.The results show that there is no obvious slip between UHPC layer and steel plate with PBL connector.Compared with the specimen with studs,the crack resistance of the specimen with PBL shear connector is slightly improved,but the stiffness of the specimens after cracking is significantly improved.The initial crack strength is increased by 3.6%,the nominal tensile strength at the crack width of 0.05 mm is increased by 3.3%,and the stiffness after cracking is increased by 52.7%.The longitudinal mechanical performance of steel-UHPC composite bridge decks is mainly affected by reinforcement ratio,while the PBL shear connector spacing and the thickness of perforated steel plates have little effect.