Abstract: Full?scale experimental tests were carried out to study the fire?resistance performance of cross?laminated timber walls in load?bearing conditions. The tested wall specimens had sizes (width×height×thickness) of 3 600 mm×4 000 mm×175 mm, and subjected to a linear load of 120 kN/m. The two tested walls were protected with one?layer of 15 mm?thick fire?resistant gypsum board and two?layers of 12 mm?thick fire?resistant gypsum boards, respectively. Test results show that, for the specimen 5W?1 protected with one?layer of 15 mm?thick fire?resistant gypsum board, the gypsum board fell off at about 55 min, and no obvious char layer delamination was observed because this specimen was made using the heat?resistant PUR adhesive. For the specimen 5W?2 protected two?layers of 12 mm?thick fire?resistant gypsum boards, the 1st layer of gypsum board fell off at about 40 min and the 2nd layer fell off at about 85 min, and the char layer delaminated after the furnace burner was terminated, because this specimen was made using the ordinary PUR adhesive. At 121 min, the vertical displacements of the wall specimens were about -10.3 mm and -9.5 mm, respectively. The unexposed sides of the wall specimens showed intact, and the temperature rise on the unexposed sides were less than 5 ℃ for the both specimens. The final results show that the two tested wall specimens have lord?bearing capacity, fire integrity and insulation not less than 2.00 h.

Key words: cross?laminated timber, load?bearing wall, full?scale, fire?resistance performance, charring rate, heat-resistant PUR adhesive