Hunan University of Science and Technology
Research of Stress Mechanism and Design Method of FRP-concrete Box Girder Structure System for Double-deck Traffic（Grand No.51578236）
Abstract: The reliable connection of pultrusion forming GFRP pipe joints is a prerequisite to ensure the normal operation of the components. In order to research its tensile connection performance, this paper adopts two kinds of connection modes of bonding connection and bolt connection in GFRP pipe and steel pipe connector, and carries out its tensile test research respectively. The distribution characteristics, force mechanism, failure process and the influence of bonding length on load-bearing capacity of glue layer shear stress along the length direction was studied in the adhesive bonding test. The experimental results show that the shear stress of the glue layer is large at both ends and small in the middle along the length direction at the initial stage of loading. As the load increased, the stress gradually shifted towards the loading end of the glue layer. The increase of bonding length can significantly improve the load-bearing capacity of the connecting parts, but when the length reaches 1.6 times of the pipe diameter, the increase of the bonding length is not obvious to the increase of the load-bearing capacity. Therefore, the 1.6 times the pipe diameter can take into account as the effective bond length of the GFRP pipe. The influence of e/d (edge distance/bolt diameter) and bolt row number on the connection load-bearing capacity and failure mode were studied in the bolt connection experiment. The experiment results show that when is equal to 7, the load-bearing capacity reaches the maximum value and the main failure mode is extrusion failure. According to the relationship between the bolt row number and the load-bearing capacity, the corresponding reduction coefficient can be deduced for calculating the load-bearing capacity.