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Glass-fiber-reinforced polymer (GFRP) composites with innovative sleeve joints are examined for space frame assembly. The sleeve joint connects one end of a steel tubular connector with a circular solid or hollow GFRP composites by adhesive bonding, the other end being flattened to enable easy connection with other members using mechanical bolts. Experiments were conducted to investigate the mechanical performance in tension and compression. In the tensile specimens, pull-out failure occurred between GFRP and adhesive when the bond length was relatively short, and tensile fracture of the steel tubular connector occurred when the bond length was sufficiently long. In the compact compressive specimens, yielding of the flattened steel tube occurred because of the bending moment at the fully fixed support. Global buckling failure was observed for slender compressive members. Load-bearing capacity was analytically estimated for different loading scenarios and compared well with experimental results.

The use of bolted sleeve joints has been proposed for assembling pultruded glass fiber-reinforced polymer (GFRP) tubular profiles into space lattice shell structures. Such joint configurations may introduce a semi-rigid end condition and further affect the capacity of the connecting members in compression. Three batches of specimens assembled with pultruded GFRP profiles of different lengths and bolted sleeve joints at both ends were prepared and tested under static axial compression. A detailed three-dimensional finite element model considering bolt geometry, contact behavior, bolt pretension, initial geometric imperfection, and failure criterion for fiber-reinforced polymer (FRP) composites was developed and validated with experimental results showing good comparisons. It was found that the bolted sleeve joints exhibited semi-rigid behavior and that the failure modes and the effective length factor were dependent on member slenderness. The relationship between effective length factor and member ...

This paper investigates bolted sleeve joints for connecting tubular pultruded fiber-reinforced polymer (FRP) sections in tubular structures such as space frames. In the proposed joint, FRP profile and steel connector are telescoped and then clamped by mechanical bolts. Four batches of specimens were prepared and tested under static axial loading (tension and compression). Design parameters, namely the type of fastener (ordinary bolt or blind bolt), member size, and bolt group layout, were selected and examined. During experiments, failure modes, load-displacement and load-strain relationships were recorded to evaluate the joint performance. A staggered pattern within a bolted sleeve joint had a negligible effect on the load distribution compared with a nonstaggered pattern. The study showed that the joint capacity could be optimized effectively by adjusting the joint geometry. When blind bolts are used, a compromise between ease of cavity fixing and joint performance must be noted. Finally, a simp...