Lagscrewbolt (LSB) has been used widely for composing glulam moment resisting column-leg as well as beam-column joints for constructing semi-rigid wooden frame structures. A serious problem on the existing LSB joint, however, was its brittle failure mode. In order to avoid this characteristic, Slotted Bolted Connection (SBC) systems, which is a kind of the friction damper for steel truss structure, was introduced to the existing glulam LSB joint system serially. Experiments on full-scale column-leg joint and beam-column joint, which were intended to be used in a three storey glulam school building, showed satisfactory performance on the requirements for the stiffness, yielding and ultimate performance. By this innovative investigation, a glulam semi-rigid portal frame, which has high initial stiffness, clear yielding capacity, rich ductility, and free from glulam brittle fractures, might be possible to be realized.
Moment resisting joint with lagscrewbolts shows good mechanical performance and aesthetic. However, beam and column joints rarely showed a brittle shear failure in a panel zone of a column in previous studies. Therefore, a joint system reinforced by long screws was developed to prevent from the failure in this research. The maximum shear strength of the joint increased with increasing the number of long screws. However, the average of six screws specimens was lower than that of four screws, because the glulam and some of the screws were damaged due to the narrow space between the screws during an inserting process of the screws.