Interfacial Behavior of the Steel–UHPC Composite Deck With Toughened Epoxy Bonding

Abstract

Using traditional stud connectors to connect the ultra-high-performance concrete layer and steel deck is detrimental to the construction speed and fatigue performance of the composite structure. Connecting the steel–UHPC interface with toughened epoxy bonding is a potential alternative to avoid this issue. To explore whether the toughened epoxy bonding interface can reduce the amount of bridge deck studs or even cancel the studs, a numerical simulation was conducted in this paper. The non-toughened epoxy bonding interface, the toughened epoxy bonding interface, a few studs + toughened epoxy bonding interface, and the full stud connection interface were designed to study the interfacial behavior of the steel–UHPC composite deck. Moreover, the constitutive model of the toughened epoxy bonding interface is verified through the direct shear test and compression-shear test. The results show that the maximum interface shear stress of the toughened epoxy bonding interface is 0.61 MPa under the standard wheel load, which is 20.78% lower than that of the non-toughened epoxy bonding interface. Under the overload, the interface failure of the toughened epoxy bonding interface is more concentrated and exhibits a smaller damage area compared with the non-toughened epoxy bonding interface. When the interface defect is 5%, the toughened epoxy bonding interface only has a few interface damages, exhibiting good defect tolerance. Compared to the traditional full stud connection interface, the interface shear stress in the few studs + toughened epoxy bonding interface is more uniform, which avoids the stress concentration in the root of studs, and the studs’ average stress is significantly reduced by 63.21%. It is verified that using the toughened epoxy bonding interface can significantly reduce the amount of studs.

Bending behavior of steel-UHPC composite bridge deck based on epoxy adhesive

“…However, insufficient stiffness of OSD can easily lead to fatigue cracking of the steel bridge deck (Fu et al, 2019) and pavement damage (Wang et al, 2020) under the coupling effect of the reciprocating vehicle and external environmental factors. Therefore, the OSD can be paved with high-performance concrete (Zhang et al, 2020;Zou et al, 2021a;Zhang et al, 2021;Jiang et al, 2022;Zhang et al, 2022) to increase its stiffness of the OSD. Ultra-high performance concrete (UHPC), a new type of steel fiber reinforced concrete (Hung et al, 2021), has good fluidity (minimum slump is 200-250 mm (Alkaysi and El-Tawil, 2017)), high strength (compressive strength greater than 120 MPa (Zhu et al, 2020), tensile strength greater than 5 MPa (Meng and Khayat, 2017)), impact resistance (Wu et al, 2019) and excellent durability (Charron et al, 2008).…”