斜拉桥索塔锚固区混合连接件受力特性与传力机理OA

Studs and perfobond connectors can be hybridized to increase the connection firmness between the steel corbel and concrete pylon in the pylon anchorage zone of cable-stayed bridges.A scaled model test combined with a practical project was carried out to clarify the mechanical behavior and force transfer mechanism of the hybrid connectors in the cable pylon.Strain,displacement,concrete cracking and failure forms of the connecting components under loads were tested.The failure process and load transfer patterns were analyzed with ABAQUS finite element analysis.The research indicated that the hybrid connectors of studs and perfobond connectors were firmly strong.Surface cracks in the concrete exhibited a radial distribution,while a conical failure surface was formed inside the concrete along the head of studs above the center height of the corbel webs,which eventually led to the overall failure.Studs and perfobond connectors showed different stress characteristics during different loading periods.The stress non-uniformity of the studs was obviously greater than that of the perfobond connectors.Failure of the studs occurred first in the hybrid connection in this paper.The shear force of the connecting components was primarily borne by the studs and the perfobond connectors,with their total shear contribution decreased from 85％to 70％as the load increased.The concrete beneath the perfobond connectors and the friction between the steel corbel and concrete handled the remaining shear forces.The current design calculations which assume the connecting components bear all shear forces are overly conservative.