斜拉桥双边工字钢-UHPC桥面板组合梁静力性能研究

针对斜拉桥传统钢-混组合梁的不足,提出双边工字钢-UHPC桥面板组合梁。以湖南马路口资水大桥为依托,分别采用有限元软件MIDAS和ANSYS建立全桥模型和主梁节段模型,分析组合梁的受力性能,制作UHPC桥面板模型试件进行弯曲试验,研究UHPC桥面板的受力性能。结果表明:荷载组合作用下,钢主纵梁、钢横梁的最大正应力分别为223 MPa、197MPa,最大剪应力分别为145MPa、65MPa,小于钢材强度设计值;顺桥向、横桥向弯曲构件破坏时的名义拉应力分别为63.2MPa、34.5MPa,初裂应力分别为23.2MPa、10.4MPa,UHPC桥面板的抗弯承载能力满足要求,且具有良好的抗裂性能。

Study on Static Behavior of Twin I-Steel-UHPC Bridge Deck Composite Girder of Cable-Stayed Bridge

In view of the shortcomings of traditional steel-concrete composite girders of cable-stayed bridges,we proposed a composite girder which is composed of twin I-steel and ultra-high performance concrete(UHPC)bridge deck.Based on Malukou Zishui Bridge in Hunan Province,a whole bridge model and a segment model of the main girder were established by using the finite element software such as MIDAS and ANSYS.The mechanical properties of the composite girder were analyzed,and the bending test of the UHPC bridge deck model was carried out to study the mechanical properties of the UHPC bridge deck.The results show that the maximum normal stresses of the main longitudinal girder and the cross beam of steel are 223 MPa and 197 MPa,respectively,under the combination action of load;the maximum shear stresses are 145 MPa and 65 MPa,respectively,which are less than the design values of steel strength.The nominal tensile stresses of the bending test component in bridge direction and transverse direction are 63.2 MPa and 34.5 MPa,respectively,and the initial crack stresses are 23.2 MPa and 10.4 MPa,respectively.The bending capacity of UHPC bridge deck meets the requirements and has good crack resistance.