Dowel-Bearing Strength Properties of Glulam with and Without Glue Line Made of Mengkulang Species

Abstract

The lateral connection of wood design strength performance to fastener bending can be estimated by dowel-bearing strength. The value from the dowel-bearing strength can be used in resolving the European Yield Model (EYM) theory. This study focus on determination the dowel-bearing strength properties of glulam with and without glue line made of Mengkulang species on the effect of two (2) different bolt diameters using 16 and 20 mm dowel diameters. The dowel-bearing strength of glulam also compared according to 5 % diameter offset and maximum load by using ASTM 5764-97a (2013) and BS 383:1993, respectively. The mean value of dowel-bearing strength, Fe using 5 % diameter offset of load for with glue line of glulam made of Mengkulang species using 16 mm dowel diameter is 11.21 N/mm2 and 20 mm is 8.88 N/mm2. The mean value of dowel-bearing strength, Fe for without glue line of glulam made of Mengkulang species using 16 mm dowel diameter is 13.33 N/mm2 and 20 mm is 11.52 N/mm2. The percentage differences of dowel-bearing strength, Fe due to effect on increasing dowel diameter for with glue line specimens is reduced 21 % and without glue line specimens is reduced 14 %. It is shown the dowel-bearing strength decreased when the dowel diameter increased. The percentage differences of dowel-bearing strength, Fe of same dowel diameter between with and without specimens using 16 mm dowel diameter is 19 % and 20 mm dowel diameter is 30 %, respectively. The results shown the dowel-bearing strength of glulam without glue line are better and higher compared to the with glue line specimens. The mean value of dowel-bearing strength, Fh using maximum load method of glulam with glue line made of Mengkulang species using 16 mm dowel diameter is 17.02 N/mm2 and 20 mm is 12.74 N/mm2. The mean value of dowel-bearing strength, Fh of glulam without glue line made of Mengkulang species using 16 mm diameter is 20.37 N/mm2 and 20 mm is 18.36 N/mm2. The percentage differences between 5 % diameter offset and maximum dowel-bearing strength for with glue line specimens using 16 mm dowel diameter is 52 % and 20 mm is 43 %. The percentage differences for without glue line specimens using 16 mm dowel diameter is 53 % and 20 mm is 59 %.