Analysis of the Bearing Capacity of PBL Shear Connector

The PBL shear connector used to connect the corrugated steel ribs and concrete roof of long-span continuous rigid frame bridges has its unique structure, mechanics, and stress environment characteristics. In order to study the load-slip properties and bearing capacities of this kind of PBL shear connectors, failure tests were carried out with static loads using 33 specimens in 13 types of 3-hole models (3 specimens for each model type), in which transverse tensile and compressive prestresses were applied to the specimens with jack and finishing rolling rebar. Through the tests, the concept and value of a design bearing capacity were proposed and fitting formulas of the design bearing capacity and the ultimate bearing capacity were obtained. The results show that when the load is smaller than the design bearing capacity, the PBL connector works in the elastic stage with a slip less than the specified limit. The load-slip curves obtained from tests can be segmented into elastic stage, elastoplastic stage, yielding stage, and partially reinforcing stage. Under a concentrated loading condition, the bearing capacity calculated by average of the load born by the 3 holes is obviously smaller than the actual value. In addition, the transverse tensile prestress reduces the design bearing capacity and ultimate bearing capacity of the PBL shear connectors by about 0.020 and 0.043 kN, respectively, while the transverse compressive prestress benefits the bearing capacity of the shear connectors. The effect of prestress on bearing capacity can be considered separately.