采用预制-现浇UHPC板的钢桥面铺装受力性能研究

为解决现有钢桥面铺装因大面积现浇超高性能混凝土(UHPC)产生收缩开裂，需密集配筋，施工现场需要大量蒸养设备等问题，提出了一种采用预制-现浇UHPC板的钢桥面铺装。通过钢-预制UHPC板界面、钢-现浇UHPC板界面和预制-现浇UHPC界面局部模型试验，揭示了采用预制-现浇UHPC板的钢桥面铺装各关键界面黏结性能；通过节段足尺模型试验与有限元分析，明确了车辆荷载下采用预制-现浇UHPC板的钢桥面铺装的荷载效应。研究结果表明：钢-预制UHPC板界面受拉和受剪破坏均发生于粘胶层与预制UHPC板结合面，法向抗拉和切向抗剪承载力可保守地取5.2 MPa和8.7 MPa；栓钉间距在150~320 mm之间时，栓钉加密对钢-现浇UHPC板界面抗剪承载力影响较小，可根据中国规范进行现浇UHPC板中栓钉承载力的计算，抗剪刚度可保守的取110.0 kN·mm^-1；界面凿毛处理和湿接缝采用蒸汽养护，可使预制-现浇UHPC接缝的抗剪强度分别提升23%和20%，预制-现浇UHPC接缝抗剪强度可保守地取2.4 MPa；在3倍车辆设计荷载作用下，UHPC板以及钢-UHPC板界面的应力均小于容许应力。提出的采用预制-现浇UHPC板的钢桥面铺装方案可行。

Study on Mechanical Performance of Steel Bridge Deck Pavement with Prefabricated and Cast-in-situ UHPC Slab

To solve the problem of shrinkage cracking, the need for intensive reinforcement and a large number of steaming equipment of orthotropic steel bridge deck pavement caused by large area of cast-in-situ ultra high performance concrete (UHPC), a new type of steel bridge deck pavement using prefabricated and cast-in-situ UHPC slab was presented. Through local specimen tests on the interfaces between steel and prefabricated UHPC slab, steel and cast-in-situ UHPC slab, prefabricated and cast-in-situ UHPC slab, the bonding properties of the key interfaces of steel deck pavement with prefabricated and cast-in-situ UHPC slab were revealed. The load effects of steel deck pavement with prefabricated and cast-in-situ UHPC slab under vehicle load were determined by full-size segment specimen test and finite element analysis. The results show that the tensile and shear failures of the interface between steel and prefabricated UHPC slab occur at the bonding surface of the viscose layer and prefabricated UHPC slab, the normal tensile and tangential shear capacity can be conservatively 5.2 MPa and 8.7 MPa; when the stud spacing is between 150 and 320 mm, the stud intensity has little effect on the shear capacity of interface between steel and cast-in-situ UHPC slab. The stud bearing capacity in cast-in-situ UHPC slab can be calculated according to the Chinese code, and the shear stiffness can be conservatively set at 110.0 kN·mm^-1; The shear strength of prefabricated and cast-in-situ UHPC interface can be respectively increased by 23% and 20% by gouging the interface and steam curing the wet joints. The shear strength of the prefabricated and cast-in-situ UHPC interface can be conservatively 2.4 MPa; Under the action of 3 times of vehicle design load, the stress of UHPC slab and steel-UHPC interface is less than the allowable stress. Therefore, the steel bridge deck pavement scheme using prefabricated and cast-in-situ UHPC slab proposed in this paper is feasible.