A new steel-concrete connection with Perfo-Bond Strip (PBL) connectors for a hybrid cable-stayed bridge was adopted and introduced. Push-out tests of the PBL connectors were performed to evaluate the shear capacity of perfobond ribs in steel-concrete connections. Test results revealed that the shear strength of a perfobond rib in a twin configuration is about 80% of that of a single independent perfobond rib. To investigate the safety and reliability of the proposed connection from a practical perspective, a model test with a scale of 1:2 for the joint of the hybrid girder was carried out on site. During the test, stress distribution, crack resistance ability, and relative slip between concrete and steel were measured carefully to investigate the mechanical performance, force transmission, strength, and stiffness of the steel-concrete connection. The test results revealed that concentrated stress at the loading section in steel girders can be reduced and transferred uniformly through the joint to ...

We present an innovative prefabricated composite box girder with corrugated webs and concrete-filled steel tube slab to prevent cracking in the web and reduce the self-weight, which is suitable for long-span structures. We carried out systematic experimental and analytical studies to investigate the structural performance, including the loading capacity and dynamic properties of a prefabricated composite box girder bridge before and after erection. Firstly, we tested a prefabricated composite girder with a single box section before erection under monotonic loading, measuring vertical deformation, flexural strain on the slabs, and shear strain on the corrugated steel webs, and evaluating the load-carrying capacity and stiffness reduction. Secondly, we conducted field live-load tests, including a calibration test and a dynamic test, on a composite bridge with twin prefabricated box girders. We hired four-axle heavy trucks for a calibration test to explore the static responses in terms of displacement, bending strain on the slabs, and shear strain on the corrugated steel webs. In the dynamic tests, we carried out a modal test using ambient vibration method and a moving load test in order to determine the dynamic behavior, which involves natural frequencies, the mode shapes, and the dynamic load factor (DLF). Based on the test results, the structural performance was evaluated by the AASHTO bridge rating process. All the findings from the load-carrying capacity test at ultimate state, calibration and dynamic load tests at service state in this study may provide a reference for the design and construction of such type of bridges.