Document k6KREmkGEMoVvwMn8Vkw6zYnD

FILE NAME: WR Grace (WRG) DATE: Unknown DOC#: WRG214 DOCUMENT DESCRIPTION: 0000 Report on Government Inspection Results. Incomplete document. - 8- In i t s s i m p l e s t form the new f i r e t e s t p r o v i d e s f o r two r a t i n g s RESTRAINED and UNRESTRAINED. Under it s p r o v i s i o n s p o rtio n s o f a b u i l d i n g can be con sid ere d re s tr a in e d while other p o r t i o n s o f the same b u i l d i n g c o u l d be u n r e s t r a i n e d . Temperature l i m i t a t i o n s have been e s t a b l i s h e d f o r a l l beams and f l o o r a s s e m b lie s but a time f a c t o r has been introduced which p r o v i d e s t h a t in the t e s t i n g o f beams in the r e s t r a i n e d c o n d i t i o n the temperature o f the s t e e l s h a l l not exceed 1100 F. av er age o r 1300 F. maximum a t any p o i n t f o r a t l e a s t one hour o r f o r one h a l f o f the c l a s s i f i c a t i o n p e r i o d . A R e s t r a i n e d beam then could be rated a t A hours i f i t s u s t a in e d i t s design load f o r A hours and the l i m i t i n g temperatures were not exceeded f o r 2 hours. In the c a s e o f U n r e s t r a i n e d beams the temperature l i m i t a t i o n s cannot be exceeded d u r in g the e n t i r e c l a s s i f i c a t i o n p e rio d . A A hour U n r e s t r a i n e d beam then would have to be p r o t e c t e d w i t h s u f f i c i e n t m a t e r i a l to prevent a temperature r i s e exceeding the 1100 F av e rag e o r 1300 F. maximum a t any p o i n t f o r the f u l l A hours. O b v i o u s l y the U n r e s t r a i n e d beam requirements are much more se v e re , and e x c e p t f o r a 100 d i f f e r e n c e in temperature are s i m i l a r to the present San F ra n c isc o , Los Angeles and the Uniform B u i ld i n g Code requirements. Floor and Roof Assembly Tests have a l s o been revised. They must be f u l l y loaded and c a r r y the loa d f o r the f u l l time p e r i o d . Temperature transm ission through the f lo o r or roof cannot exceed 250o F. a v e r a g e or more than 325o F. a t any p o i n t . C ot t on waste w * 9- on the unexposed s id e cannot i g n i t e from passage o f hot gas or . flame. T h is p o r t i o n of the t e s t procedure has not been changed but a new element has been added. The beam s u p p o r t i n g the f l o o r or r o o f a s s e m b l y is now c o n s i d e r e d an integra-1 p a r t o f the assembl The requirements f o r the beams in r e s t r a i n e d or u n r e s t r a i n e d f l o o r or r o o fs is i d e n t i c a l to thos e o u t l i n e d p r e v i o u s l y f o r beams o n l y . In u n r e s t r a i n e d f l o o r s or ro o fs one o ther p r o v i s i o n has been added. The temperature o f the ste e l from which the deck is f a b r i c cannot exceed 1100 F. d u r i n g the e n t i r e c l a s s i f i c a t i o n p e r i o d . Column t e s t s have n o t been changed. F a i l u r e is based on temperature and o c c u r s when temperatures exceed 1000 F. a t any q u a r t e r s e c t i o n o f the member or 1200 F. a t any s i n g l e p o i n t . Th same t e s t pro ce du re and temperature l i m i t a t i o n s are a p p l i c a b l e to both ste e l and concrete construction.. The whole t e s t procedure has been fu rt h e r complicated by fa i o f the E-5 Committee to define RESTRAINT in r e a l i s t i c terms. It reads as f o l l o w s " F l o o r and Roof A s s e m b l i e s and i n d i v i d u a l beams in b u i l d i n g s s h a l l be c o n s i d e r e d r e s t r a i n e d when the s u r r o u n d i n g or supporting structure is capable of re sistin g substantial them' expansion throughout the range of an ticip ated elevated temperatur Constructio ns not complying with th is d e f i n i t i o n are assumed to ~ f r e e to r o t a t e and expand and s h a l l , t h e r e f o r e , be c o n s id e r e d as unrestrained." 10- T h i s language is s o broad and s o vague t h a t many fe el th at . o n l y the s t r u c t u r a l e n g in e e r who d e s i g n e d the b u i l d i n g can determine what is restra in e d or unrestrained. There are even those who i n s i s t t h a t such a d e t e r m i n a t i o n cannot be made r e a l i s t i c a l l y ^ f h a t f i r e l o a d i n g changes in s t r u c t u r e s and who can say what is " s u b s t a n t ia l thermal expansion" or "a n tic ip a te d e l e v a t e d t e m p e r a tu r e s " . I t is t h i s group who have f o r p r a c t i c a l pu rpo ses r e j e c t e d the "RESTRAINED" c r i t e r i a and w i l l use the more p ra c tica l "UNRESTRAINED" condition. The next few years w i l l be d i f f i c u l t and r i s k y f o r everyone concerned but i t w i l l be p a r t i c u l a r l y s o f o r those who are b i d d i n g and are doing the f i e l d a p p lic a t io n . There is reason to b e l i e v e th at there w i l l not be agreement among Code A u t h o r i t i e s on the s u b j e c t ^ - Some w i l l adopt the new c r i t e r i a oth e rs w i l l r e j e c t i t . There w i l l be v a r y i n g time schedules fo r adoption or re je ctio n even by communities operating under the same b a s i c code. Extreme c a u tion p lu s r e l i a n c e on q u a l i f i e d m ate rial manufacturers r e p r e s e n t a t i v e s w i l l be n e c e s s a r y u n t i l some o f the u n re s o lv e d i s s u e s are settled. . / /