Effects of nailing and connections on the lateral resistance of CLT wall panels composed of larch square timber core and plywood cross band

Thinned small larch logs have small diameter and do not have any value-added final use except pallet, wood chip or fuel wood that are economically very low value products. However, the mechanical properties thinned larch small logs are strong enough to be used for structural purposes. In this study, small larch logs were sawn, dried and finished to produce square timbers with 90mm × 90mm cross section, which were glued laterally to form core panels used to manufacture CLT wall panels. And 12mm thick structural plywood panels were attached as cross bands on the surface and the back of larch square timber core panel by either means of gluing and pressing(CGCLT), and gluing and nailing(NGCLT) to manufacture three-layer CLT wall panels. Two CLT wall panels of the size 1, 220mm × 2, 440mm were connected to each other by T&G joint with nailing(NJ), gluing and nailing(NGJ) and nailing and gluing with two connectors(NGCJ) to produce 2, 400mm × 2, 400mm wall specimens which were tested under cyclic lateral shear forces in accordance with KS F 2154. To connect these CLT specimens to foundation of sill plate, two 910mm long steel straps were used to hold both ends of CLT panels instead of hold down. To make connections between CLT panels and sill plate, steel plates were used instead of anchor bolts. The space between steel plates was 600mm and 50mm long screws were used to fasten the steel plates to CLT as well as to sill plates. The results of lateral-load resistance tests showed that glued and nailed CLT(NGCLT) was stronger than glued and pressed CLT(CGCLT), gluing and nailing T&G connection(NGJ) was stronger than nailing connection(NJ), and nailing and gluing connection with two connectors(NGCJ) was stronger than nailing and gluing connection(NGJ).