Field Notching and Drilling of Glued Laminated （场开槽和胶合板的钻探）.pdf

T E C H N I C A L N O T E Field Notching and Drilling of Glued Laminated Timber Beams Number EWS S560E positioned on the top and bottom. The It is important to understand that November 2003 highest grade of material is used as the improperly made field notches or holes outermost laminations on the tension may reduce the capacity of a properly Introduction side of the beam. Because of this, any designed member to the point where a drilling, dapping or notching that takes structural failure may occur. The effects Glued laminated timber (glulam) beams place in these outermost tension lamina- of any field notching or drilling should be are highly engineered components manu- tions has a two-fold effect on the strength checked by a designer competent in factured from specially selected and and serviceability of the beam. First, such engineered timber design. positioned lumber laminations of varying modifications reduce the section of the strength and stiffness properties. These beam. Second, they remove wood fiber Notching fabricated beams are often specified from the laminations having the highest where a certain span, strength and/or strength. Given this, along with the fact Notching of bending members should be stiffness is required. As such, glulam that stress concentrations occur in such avoided whenever possible, especially on the tension side of the member. Tension beams are generally designed for and areas created by