Experimental study on fire-resistance performance of full-scale load-bearing cross-laminated timber floors
Experimental tests were carried out to study the fire-re-sistance performance of cross-laminated timber floors with full-scale size in load-bearing conditions.The tested floor specimens were 175 mm in thickness,and loaded with averagely-distributed weight of 2.0 kN/m2.The two tested floors were made using heat-resistant PUR adhesive and ordinary PUR adhesive,and pro-tected with one-layer of 15 mm-thick fire-resistant gypsum board and two-layers of 12 mm-thick fire-resistant gypsum boards.Test results show that,for the floor specimen using heat-resistant PUR adhesive and protected with one-layer of 15 mm-thick fire-resistant gypsum board,the gypsum board fell off at about 45~55 min,and no obvious char layer delamination was observed.For the floor using ordinary PUR adhesive and protected with two-lay-ers of 12 mm-thick fire-resistant gypsum boards,the 1st layer of gypsum board fell off at about 30 min,and the 2nd layer fell off at about 60 min,and the char layer delaminated at about 85~110 minutes.At 121 minutes,the vertical displacements at the center of floor specimens were about-25 mm and-33 mm,respec-tively.The unexposed sides of the floors showed intact,and the temperature rise on the unexposed sides were less than 2℃for the both specimens.The final results show that the fire resistance rating of two tested floors is not less than 2.00 h.