【国外标准】 Standard Practice for Evaluating Elevated Temperature Performance of End-Jointed Lumber Studs

5.1 End-jointed lumber studs used in fire resistance-rated assemblies shall be able to support the superimposed design load for the specified time under an elevated temperature exposure, when a wall assembly is exposed to a standard fire specified in Test Methods E119. Light-weight wood assemblies utilize gypsum wallboard or other types of membrane protection to accomplish a requisite fire resistance rating for the assembly. However, wood studs and the end joints in the studs shall resist the developed elevated temperature environment for the duration of the rating. This practice provides a method for evaluating the elevated temperature performance of an assembly constructed with end-jointed studs having fire performance comparable to an assembly constructed with solid-sawn studs.1.1 This practice is to be used to evaluate the elevated temperature performance of end-jointed lumber studs.1.2 A symmetric wall assembly containing end-jointed lumber studs is exposed to a standard fire exposure specified in Test Methods E119.1.3 End-jointed lumber studs are deemed qualified if the wall assembly resists a standard fire exposure specified in Test Methods E119 for a period of 60 min or more. Qualification of end-jointed lumber studs are restricted to the joint configuration and adhesive tested.1.4 This practice is used to evaluate the performance of end-jointed lumber studs to heat and flame under controlled conditions, but does not by itself incorporate all factors required for fire hazard or fire risk assessment under actual fire conditions.1.5 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are for information only.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.