Baochun Chen

Studies of In-Plane Ultimate Loads of the Steel Truss Web-RC Composite Arch

AbstractThis paper describes an experiment on the in-plane mechanical behaviors of the steel truss web–RC composite arch subjected to the unsymmetrical concentrated loads applied simultaneously at the 2/3 and 5/6 span points of the arch. The experimental results show that loads were transmitted as shear forces through the steel truss webs. The maximum measured strain in two steel tubes near the cross section at the 5/6 span point was less than the yield strain, and punching shear failure was observed at the loading sections. Using the experimental model, the authors developed and performed a finite-element simulation. They found that double N-shaped webs might be the most conducive to the stiffness and bearing capacity of the composite arches and require comparatively less steel. The critical wall thickness of the web tubes at which punching shear failure occurred was 3.5 mm for this arch model. Given the same wall thickness, the ultimate bearing capacity of the composite arch decreased as the incline ang...

Experimental Behavior and Design of CFT-RC Short Columns Subjected to Concentric Axial Loading

AbstractConcrete-filled steel tube (CFT)–RC composite members consist of multiple CFT columns connected by RC plates or webs. CFT-RC composite members have been used in different types of structure...

Rehabilitation and Retrofitting of a Multispan Simply-Supported Adjacent Box Girder Bridge into a Jointless and Continuous Structure

AbstractThe widely-utilized multispan simply-supported adjacent (side-by-side) box girder bridges often suffer from problems of deterioration attributable to transverse cracking in link slabs betwe...

Parameter Analysis of the Mechanical Performance of Hinged Hollow-Slab Bridges with Gate-Type Steel Bars at the Bottom Part of the Junction Surface

The evolution of hinged joint structures in Chinese hinged hollow-slab bridges was summarized to study the mechanical performance of hinged joint structures in hinged hollow-slab bridges with gate-type steel bars. Parameter analysis was conducted with the nonlinear finite element method for a hollow slab bridge with a span of 8 m. The failure mode of the hinged joint structure with different parameters, including crack-occurring load and crack distribution, was studied. Countermeasures to improve the hinged joint structure were also discussed. Results showed that adopting a gate-type steel bar at the bottom of the junction surface did not improve the crack-occurring load of the hinged joint, but the load of the full-length crack was improved, and the occurrence of vertical full-length cracks on the junction surface and longitudinal cracks on the hinged joint was delayed. Increasing the diameter of the gate-type steel bar did not enhance the crack-occurring load, the load of full-length cracks on the junction surface, and the final distribution of cracks. Enhancement of the concrete strength did not improve the mechanical property of hollow slab and the junction surface remarkably. By contrast, enhancement of the bond strength of the junction surface improved the crack-occurring load of the hinged joint and reduced the distribution of cracks. Three layouts of reinforcement in the hinged joint and increasing the diameter of the gate-type steel bar, as proposed in existing references, did not fundamentally improve the mechanical property of the junction surface.