Experimental study on shear behavior of adhesive-bolted hybrid connection under cyclic load

This research proposes a form of adhesive-bolted hybrid connection and investigates its shear performance under cyclic loading. The primary objective of this study is to enhance the shear bearing capacity of high-strength bolt friction-type connections while simultaneously reducing the total number of bolts required. Through cyclic loading tests on 8 groups of 24 specimens with different bolt specifications and hole-type combinations, analyzing the variation of the slip coefficient, stable slip coefficient, and the bolt pretensioning force on the contact surface. Then compared with the test results of adhesive-free bolt connection specimens under the same conditions. The results showed that the slip coefficient of the double shear specimens was approximately 50% higher and that of the single shear specimens was approximately 30% higher than that of the adhesive-free bolted specimens. The slip coefficient for double shear specimens ranges from 0.50 to 0.76, while for single shear specimens, it ranges from 0.55 to 0.66. During the stable slip phase, the stable slip coefficient of double shear specimens is roughly 34% higher than that of specimens with adhesive-free bolt connections and no significant increase is observed in single shear specimens. At the end of the test, the bolt pretensioning force may decrease by up to 23% in double shear specimens and 30% in single shear specimens.