Sheet steel as a protective membrane for steel beams and columns

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Sheet steel as a protective membrane for steel beams and columns

Stanzak, W. W.

NATIONAL RESEARCH COUNCIL O F CANADA DIVISION O F BUILDING RESEARCH

S H E E T S T E E L AS A PROTECTIVE MEMBRANE FOR S T E E L BEAMS AND COLUMNS

W. W. Stanzak

F I R E STUDY NO. 23

of t h e

DIVISION O F BUILDING RESEARCH

Ottawa

S H E E T S T E E L AS A PROTECTIVE MEMBRANE FOR S T E E L BEAMS AND COLUMNS

by

W. W. Stanzak*

A p r o t e c t i v e m e m b r a n e is a continuous l a y e r s e p a r a t i n g the m e m b e r to be p r o t e c t e d f r o m the f i r e , without coming into d i r e c t t h e r m a l contact with the m e m b e r .

This r e p o r t d e s c r i b e s the r e s u l t s of f i r e t e s t s on a s t e e l beam and two columns, protected with insulating m a t e r i a l s enclosed i n a s h e e t s t e e l m e m - b r a n e c a s e .

The p r a c t i c e of protecting s t r u c t u r e s a g a i n s t f i r e by a p r o t e c t i v e m e m - b r a n e h a s been c a r r i e d out f o r m a n y y e a r s . I t was only i n the l a t e 19501s, however, t h a t p r o t e c t i v e m a t e r i a l s other than p l a s t e r and gypsum wallboards w e r e used widely a s m e m b r a n e f i r e protection. T h i s development was due t o a m a r k e d i n c r e a s e in the number of s p o n s o r e d f i r e t e s t s c a r r i e d out by m a - t e r i a l s m a n u f a c t u r e r s .

A f i r e t e s t on a s t e e l b e a m protected with a m e m b r a n e of gypsum-sanded p l a s t e r h a s been d e s c r i b e d in DBR F i r e Study No. 19 (1). The r e s u l t s of 8 f i r e t e s t s on s t e e l column sections protected with gypsum-sanded p l a s t e r a r e given i n F i r e Study No. 2 0 (2).

The available f i r e t e s t data, a s well a s s o m e t e s t s in a s m a l l f l o o r f u r n a c e ( 3 ) c l e a r l y show t h a t t h e m o s t v i t a l c h a r a c t e r i s t i c of a p r o t e c t i v e m e m - b r a n e i s i t s ability to r e m a i n in place. This was d e m o n s t r a t e d in the s m a l l f u r n a c e by the f a c t that a 16-ga (0.0598 in. ) s t e e l s h e e t m e m b r a n e i n c r e a s e d the f i r e e n d u r a n c e t i m e of a b r i c k floor by about 2 3 p e r cent. I n s e r t i n g a lightweight m i n e r a l wool i n the a i r g a p between the s t e e l and the b r i c k r e s u l t e d i n a 220 p e r c e n t i n c r e a s e in the f i r e endurance time.

In addition to its ability to r e m a i n in place, a protective m e m b r a n e , to b e r e a l l y effective, should have a low t h e r m a l conductivity and a high t h e r m a l capacity. M a t e r i a l s displaying t h e s e p r o p e r t i e s a r e r a t h e r expensive and h a r d to find. Unfortunately, many m a t e r i a l s that a c t a s good i n s u l a t o r s d e t e r i o r a t e

s e r i o u s l y f r o m t h e effects of f i r e and b e c o m e p r e m a t u r e l y dislodged. I t h a s been difficult, t h e r e f o r e , to develop m e m b r a n e protection to i t s full potential.

Sheet s t e e l h a s not been previously c o n s i d e r e d a s a potential f i r e p r o - t e c t i v e m a t e r i a l . However, i t s ability to r e m a i n in place, and the f a c t that

i t s p r e s e n c e a s a radiation shield c a u s e s the f i r e endurance t i m e of a con- s t r u c t i o n to i n c r e a s e , suggested t h a t this possibility should b e investigated. PART I : BEAM TEST

DESCRIPTION O F SPECIMEN

Details of the t e s t s p e c i m e n a r e shown in F i g u r e 1. F i g u r e 2 shows the exposed s u r f a c e of the b e a m installed in the furnace, and F i g u r e 3 shows the unexposed s u r f a c e and hydraulic loading equipment. The i t e m n u m b e r s below c o r r e s p o n d t o the p a r t n u m b e r s in F i g u r e 1.

1. S t e e l wide-flange beam, 8 in. by 5: in by 17 lb/ft, 16 f t 0 in. long, s t e e l specification CSA G40. 12.

2. Haydite Slab, 4 by 31 by 36 in., a v e r a g e density 106 lb/ft3. 3. S t e e l plate,

$

by 18 by 36 in. tack welded to s t e e l beam.

4. M i n e r a l wool insulation, 3 in. thick (Johns Manville Type 413). 5. Sheet s t e e l m e m b r a n e , b r a k e - f o r m e d f r o m 36 in. by 48 in.

galvanized 20 ga (0. 0359) s h e e t s . 6. R e f r a c t o r y insulation.

TEST METHOD

The f i r e t e s t was c a r r i e d out e s s e n t i a l l y in a c c o r d a n c e with a tentative r e v i s i o n of ASTM specification E119-61: T e s t s of Loaded B e a m s (4). A de- viation f r o m the specification was t h a t the f l o o r s l a b was l e s s than the m i n i - m u m 5-ft width specified.

F u r n a c e t e m p e r a t u r e was m e a s u r e d by nine s y m m e t r i c a l l y disposed thermocouples enclosed in a 131 16 in. 0. D. Inconel tube having 0. 035 in. wall thickness. The hot junctions of the thermocouples w e r e in c a r b o n s t e e l c a p s on the Inconel tubes and w e r e placed 12 in. below the plane of the u n d e r s i d e of the f l o o r slab. Both the individual t e m p e r a t u r e s a t nine points of the f u r - nace and the a v e r a g e of the nine thermocouples w e r e r e c o r d e d . The f u e l in- put into the f u r n a c e was controlled automatically in such a way that the a v e r a g e t e m p e r a t u r e c l o s e l y followed the p r e s c r i b e d s t a n d a r d t e m p e r a t u r e - t i m e c o r - relation.

The s t e e l t e m p e r a t u r e s w e r e m e a s u r e d by 16 c h r o m e l - a l u m e l t h e r m o - couples, peened into the b e a m a t locations shown in F i g u r e 4. T e m p e r a t u r e s w e r e m e a s u r e d a t four sections, s y m m e t r i c a l l y located along the length of the beam. One of the thermocouples was located on the bottom flange a t m i d - span, a s a hot region was expected to develop t h e r e .

The b e a m was loaded s o a s to develop the s t r e s s e s contemplated by the design. A typical loading calculation f o r a b e a m t e s t i s given in Appendix A of R e f e r e n c e 1. Load was applied by two p a i r s of hydraulic jacks, e a c h p a i r connected with a c r o s s - b e a m , 36 in. on e i t h e r s i d e of midspan.

V e r t i c a l deflections w e r e m e a s u r e d a t the c e n t r e and q u a r t e r points of the span by m e a n s of t h r e e m e a s u r i n g t a p e s connected to the floor s l a b by a m e c h a n i c a l s y s t e m . The a c c u r a c y of the m e a s u r e m e n t s i s f 0.01 in.*

OBSERVATIONS DURING FIRE TEST

The deflection due to the applied live load was 0.75 in. This was c l o s e enough to the calculated t h e o r e t i c a l deflection of 0.775 in. to indicate t h a t the r e q u i r e d l i v e load was being c a r r i e d by the beam.

0 rnin

-

f i r e on

10 rnin

-

s h e e t m e t a l protection s t a r t e d bulging w e s t of the c e n t r e of the beam

15 rnin

-

thermocouple No. 11 on the s t e e l b e a m n e a r the bulge r e g i s t e r e d higher readings than corresponding t h e r m o - couples a t other stations

90 rnin

-

b e a m bowed evenly downward without l a t e r a l deformation. P r o t e c t i o n s t i l l in place and without gaps, but warped in places.

97 rnin

-

explosive spalling a t c e n t r e of c o n c r e t e s l a b on the north s i d e

103 rnin

-

t e s t t e r m i n a t e d due to e x c e s s i v e deflection of the beam; f i r e out and load removed.

RESULTS

The t e m p e r a t u r e r i s e c u r v e f o r the beam is given i n F i g u r e 5 and the deflection c u r v e i n F i g u r e

6.

In o r d e r that f i r e t e s t s might be t e r m i n a t e d p r i o r to, but reasonably c l o s e t o ultimate collapse, Robertson and Ryan (5) proposed that the point

*

In b e a m t e s t s in which the deflection w i r e i s attached to the floor slab, de- flection r e a d i n g s m a y be e r r a t i c during e a r l y portions of the f i r e exposure. Warping of the floor s l a b o r f a i l u r e of the s l a b t o follow the deflection of the b e a m a r e r e s p o n s i b l e f o r this. Deflections during the final s t a g e s of the f i r e t e s t a r e , however, usually quite r e l i a b l e , b e c a u s e by this t i m e the s l a b h a s weakened sufficiently t o follow the deflection of the beam closely.

a t which both 6

-

r

a

800

'"

d and 6 ; 2 150 d c a n be r e g a r d e d a s a n indication C

of load f a i l u r e . In t h e s e e x p r e s s i o n s 6 = c e n t r a l deflection, in. ; 6 ; = r a t e C

of deflection, in. / h r ; A = c l e a r span of p r i n c i p a l s t r u c t u r a l element, i n . , and d = d i s t a n c e between the upper and lower e x t r e m e f i b r e s of the p r i n c i p a l s t r u c - t u r a l element, in. The c r i t i c a l r a t e of deflection was not exceeded during the f i r e t e s t , although the deflection was l a r g e . T h e r e f o r e , no load f a i l u r e oc- c u r r e d according to the Robertson/Ryan c r i t e r i a .

When the t e s t was t e r m i n a t e d (103 m i n ) the b e a m had a l a r g e c e n t r a l deflection and could obviously no longer p e r f o r m i t s s t r u c t u r a l function. The f i r e endurance t i m e of t h e s p e c i m e n may, t h e r e f o r e , b e a s s i g n e d a t 103 ~ n i n .

The f i r e r e s i s t a n c e classification i s I + h r . CONCLUSIONS

1. The f i r e endurance t i m e of the s p e c i m e n was 103 m i n providing a f i r e r e s i s t a n c e classification of 1$ h r .

2. The a v e r a g e t e m p e r a t u r e on the lower flange of the b e a m was 1 2 7 0 ° F when the t e s t was t e r m i n a t e d . This i s about 100" higher than the c r i t i c a l t e m p e r a t u r e f o r non-composite b e a m s of ASTM A-36 s t e e l ( 6 ) . However, 1270" F should not be r e g a r d e d a s the c r i t i c a l t e m p e r a t u r e f o r non-

c o m p o s i t e b e a m s of CSA G40. 12 s t e e l , as load f a i l u r e according to the R o b e r t s o n Ryan c r i t e r i a had not o c c u r r e d when the t e s t was t e r m i n a t e d .

-

3. A s i m i l a r l y c o n s t r u c t e d s p e c i m e n having a b e a m of A-36 s t e e l would

f a i l a t about 75 m i n ( a s s u m i n g a c r i t i c a l t e m p e r a t u r e of 1 1 7 0 ° F ) and r e - c e i v e a f i r e r e s i s t a n c e rating of 1 h r . T h e r e f o r e a b e a m (CSA G40. 12) having s u p e r i o r c r e e p p r o p e r t i e s yields a substantial i n c r e a s e in f i r e endurance time.

COMMENTS

The f i r e t e s t c l e a r l y d e m o n s t r a t e d that the concept of a s h e e t s t e e l p r o t e c t i v e m e m b r a n e f o r wide-flange b e a m s is valid. Although t h e p r e s e n t t e s t yielded a f i r e endurance t i m e of only I $ hr, i t should b e p o s s i b l e to de- velop a n economical f o r m of protection capable of providing a 2-hr f i r e r e - s i s t a n c e using the s h e e t s t e e l m e m b r a n e .

This was the f i r s t t e s t on a CSA G40. 12 b e a m to be conducted a t this l a b o r a t o r y . The s u p e r i o r c r e e p p r o p e r t i e s of the CSA G40. 12 s t e e l give the b e a m excellent f i r e enduring qualities.

PART

II:

COLUMN TESTS

This portion of the r e p o r t d e s c r i b e s two f i r e t e s t s conducted on s t e e l column sections protected with insulating m a t e r i a l s enclosed by a s h e e t m e t a l m e m b r a n e . The insulating m a t e r i a l s w e r e chosen, not only f o r t h e i r economy, but b e c a u s e they a r e not p r o p r i e t a r y products.

T h e t e s t s w e r e c a r r i e d out in the DBR floor f u r n a c e and the s p e c i m e n s w e r e not loaded.

DESCRIPTION O F TEST SPECIMENS

Construction d e t a i l s of a typical t e s t s p e c i m e n a r e shown in F i g u r e 7. The i t e m n u m b e r s below c o r r e s p o n d to the p a r t n u m b e r s in the figure.

Specimen No. 1.

1. Wide-flange s t e e l column section: 10 WF 112, 8 f t 4 in. long, S t e e l Specification ASTM A36-61 T.

2. I-in. M e s h Chicken Wire (0. 028 in. d i a m e t e r ) , galvanized. 3 . M i n e r a l Wool Building Jhsulation

( a ) Conforms to CSA Standard A 101 (7), Type 1A. ( b ) Dimensions: 3 by 23 by 48 in.

( c ) Composition: M i n e r a l wool f i b e r s produced f r o m b l a s t f u r n a c e slag.

( d ) Mechanical and P h y s i c a l P r o p e r t i e s :

Resilience: r e t u r n s t o r e f e r e n c e thickness a f t e r r e l e a s e . Weight: 3.6 l b p e r batt.

Density: 1 . 9 lb p e r cubic foot.

Btu/in. T h e r m a l conductivity (in oven-dry condition a t 7 5 ° F ) : 0.28

1 ( h r ) ( f P

I("

F

4. Standard Gypsum wallboard, ,-in. thick.

5. _{26 qa (0. 0217) wiped zinc galvanized sheet s t e e l .}

6. # 8 Sheet M e t a l Screw, 318 in. long a t 8-in. 0. C. The outside dimensions w e r e 1 8 by 18 in.

Specimen No. 2

1. Wide-flange s t e e l column section: 8 W F 48, 8 f t 4 in. long, S t e e l Specification ASTM A36-61T. Other d e t a i l s of this s p e c i m e n w e r e the s a m e a s f o r No. 1 except that the gypsum wallboard ( p a r t No. 4 )

was not included.

The outside dimensions w e r e 14 by 16 in. CONSTRUCTION O F TEST SPECIMENS

All construction was c a r r i e d out by m e m b e r s of the staff of the Division of Building R e s e a r c h .

The b a r e columns w e r e wrapped with chicken wire, lapped approximately 5 in. a t the v e r t i c a l joint, and tied with 0. 040 in.

stove-pipe w i r e about 8 in. on c e n t r e . The insulation, in 4 - f t lengths was tied in position to this inner m e s h with four p i e c e s of t i e w i r e p e r piece, s y m m e t r i c a l l y placed. The outer m e s h was then applied over the insulation in the s a m e m a n n e r d e s c r i b e d above.

F o r Specimen No. 1 gypsum wallboard was c u t and applied in the 8-foot direction by tying a t 3 locations with 0. 064 in. soft black s t e e l t i e wire. One t i e was located a t the c e n t r e and the o t h e r s w e r e about 8-in. f r o m the top, bottom and end plates. The wallboard was not applied to Specimen No. 2.

The s h e e t steel, supplied in 8 - f t lengths, had been b r a k e f o r m e d into unequal leg U-channels a s shown in F i g u r e 7. Two such channels w e r e fitted together on e a c h column and fastened a t the joints with s h e e t m e t a l s c r e w s s p a c e d approximately 8-in. on c e n t r e .

The workmanship was judged to be good. F i g u r e 8 shows both columns under construction; the one on the r i g h t i s Specimen No. 1. F i g u r e 9 shows Specimen No. 2 completed and r e a d y to i n s t a l l in the f u r n a c e .

TEST METHOD

The f i r e endurance t e s t s w e r e c a r r i e d out e s s e n t i a l l y in a c c o r d - a n c e with CSA Standard B54.3- 1964 (8): A l t e r n a t e t e s t s of P r o t e c t i o n F o r S t e e l Columns. The t e s t deviated f r o m the s t a n d a r d in m e a s u r i n g the t e m p e r a t u r e on t h e column by using only 9 thermocouples a t 3 levels, a s shown i n F i g u r e 10. Two i n t e r m e d i a t e l e v e l s w e r e omitted b e c a u s e t h e r e was no r e a s o n t o expect f a i l u r e a t t h e s e c r o s s - s e c t i o n s . The c h r o m e l - a l u m e l thermocouples w e r e peened into the s t e e l section, and r e a d i n g s w e r e r e c o r d e d on a multi-point r e c o r d e r e a c h minute during the t e s t .

The f u r n a c e t e m p e r a t u r e was m e a s u r e d by nine thermocouples i n s t a l l e d in a m e t a l f r a m e c o n s t r u c t e d f r o m 13

/

16-in. 0 . D. Inconel

tubes having 0. 035-in. wall thickness. The location of the f u r n a c e t h e r m o - couples is shown in F i g u r e 11. The hot junction of the thermocouples was

12 in. away f r o m the s u r f a c e of the specimen. Both the individual t e m - p e r a t u r e s a t nine points of the f u r n a c e and the a v e r a g e of the nine t h e r m o - couples w e r e r e c o r d e d . The f u e l input to the f u r n a c e was controlled to m a k e the a v e r a g e t e m p e r a t u r e follow a s c l o s e l y a s p o s s i b l e the p r e s c r i b e d t e m p e r a t u r e v e r s u s t i m e curve. The elevation of the b u r n e r s in the DBR floor f u r n a c e i s approximately a t level 3 on the column. In p a s t

t e s t s at this laboratory, failure has often occurred

at

t h i s level, due t o

slightly higher furnace ternperatur es. H o w e v e r , this was not the c a s e in either

of t h e s e t e s t s , for reasons which will become apparent in subsequent

sections.

Figure 12 shows column No. 2 installed in the furnace immediately before t h e f i r e test.

OBSERVATIONS

DURING FIRE

TESTS Test. No. 1

uring the f i r s t ten minutes the furnace was dark, making obser

-

vations difficult. However, flaming was seen at the joints of the sheet m e t a l a t 3 minutes, and the flaming continued until about 30 rninut es. By this t i m e the furnace t e m p e r a t u r e was sufficiently high t o permit good observations, and it was noticed that the s t e e l cover was warping somewhat and appeared t o be oxidizing on the surface. The warping, never too severe, continued progressively until about 2 hours. At 2 hours the

sheet steel cover buckled outward slightly below the c e n t r e of the column

t h u s exposing the r o c k w o o l insulation near the top directly to the f i r e . At 2 hours and 8 minutes the s t e e l had slid well down the column (about 18 in. ) and the rock wool insulation had a l s o moved, s o that about

6

in. of the s t e e l section at the top was exposed t o t h e f i r e . By 2 hours and

15 minutes 18 in. of the column w e r e b a r e , and the sheet s t e e l had warped and collapsed t o about 3 ft f r o m the top of the specimen. Only rock wool showed above the steel; not the gypsum wallboard.

The f i r e t e s t was terminated a t 2 hours and 20 minutes. Figure 1 3 shows the condition of the column s t i l l in the furnace after the f i r e t e s t . Figure 1 4 was taken after the column had been removed from the furnace and the sheet s t e e l and gypsum wallboard had been discarded.

T e s t No. 2

Nothing visibly significant happened throughout the t e s t . At 50 minutes the s t e e l was still in good condition, although slightly bulged in certain a r e a s . No vertical movement of the protection was observed throughout the t e s t .

The f i r e t e s t was terminated at 58 minutes. Figure 1 5 shows the condition of the specimen in the furnace after the t e s t , and Figure

16

is a picture of the column outside the furnace with the insulation removed. The closeup in Figure 1 7 shows the condition of the rock

wool insulation at the joint. This occurred at the mid height (level 2 ) of the column.

RESULTS

The average furnace t e m p e r a t u r e during the f i r e t e s t s was always within the allowable limits. Figure 18 is a plot showing the t e m p e r a t u r e r i s e of the columns.

Specimen No. 1 failed at level 1 at 135 minutes.

Specimen No. 2 exceeded the 1000" F allowable average t e m p e r a t u r e at level 2 (centre) a t 5 2 minutes.

Accordingly the specimens would receive f i r e endurance classifications of 2-hr and 3/4-hr respectively.

COMMENTS

These t e s t s both had interesting failures. The sliding down of insulation on specimen No. 1 caused the failure to occur at level 1, because only the rock wool remained a s insulation a t that height. It i s also possible, that because about 18 inches of the s t e e l column was exposed directly t o the f i r e , vertical heat conduction along t h e s t e e l section made a contribution t o the higher t e m p e r a t u r e s at level 1. At the t i m e of failure (135 min) the average t e m p e r a t u r e at level 1 was 110" F higher than the next highest average t e m p e r a t u r e at level 2.

Specimen No. 2 failed at level 2, which i s where the joint in t h e r o c k wool insulation o c c u r r e d ( F i g u r e 17). This r e s u l t emphasizes t h e importance of placing thermocouples at such locations. At the t i m e nf failure ( 5 2 rnin) the average t e m p e r a t u r e at level 2 was 95 to 100'

higher than levels I and 3, which w e r e at approximately the s a m e average temperature.

The sheet m e t a l was chosen, in addition t o i t s f i r e resisting abilities, for i t s attractiveness and durability as a column cover. Its p r i m a r y function, however, is t o act a s a radiation shield, and in the c a s e of s p e c h e n No. 1, t o hold t h e deteriorating wallboard insulation in place. That i t performed the latter function for a long t i m e was shown c l e a r l y by the way the s t e e l cover suddenly collapsed due to buildup of the disintegrated wallboard near the bottom. If thicker s t e e l had been used, the collapse would have occurred at a l a t e r time. (Measurements on the s t e e l a f t e r the t e s t showed that it had oxidized to an average

N e v e r t h e l e s s , i t was shown that inexpensive insulating m a t e r i a l s , protected by a c o v e r of a s h e e t s t e e l m e m b r a n e , c a n provide f i r e protection to s t e e l column s e c t i o n s f o r up t o 2 h o u r s .

P A R T Ilk CONCLUSIONS

1. The s h e e t s t e e l m e m b r a n e c a s e , i n conjunction with inexpensive insulating m a t e r i a l s was shown to provide:

( a ) f i r e endurance classification of l $ - h r f o r a s t e e l b e a m

( b ) f i r e endurance classification of 3 1 4 to 2 - h r f o r s t e e l columns

2 . _{Thin s h e e t steel, when applied a s a p r o t e c t i v e m e m b r a n e ,}

r e m a i n s in p l a c e f o r p e r i o d s of o v e r 2 hours.

3 . Sheet s t e e l is effective a s a m e m b r a n e protection when applied o v e r insulation on v e r t i c a l l y and horizontally placed m e m b e r s o r construction components.

ACKNOWLEDGEMENT

The author wishes to thank M r . E. P o r t e o u s and M r . J. Berndt, who c a r r i e d out the f i r e t e s t s .

REFERENCES

1. Stanzak, W. W. F i r e t e s t on a s t e e l wide-flange b e a m p r o t e c t e d with a one-inch gypsum-sanded p l a s t e r suspended ceiling m e m - brane. National R e s e a r c h Council of Canada, Division of Build- ing R e s e a r c h . F i r e Study No. 19, Ottawa, Aug. 1967.

(NRC 9764).

2. Stanzak, W. W. F i r e t e s t s on s t e e l wide-flange column

s e c t i o n s protected with gypsum- sanded p l a s t e r . National R e s e a r c h Council of Canada, Division of Building R e s e a r c h . F i r e Study No. 20, Ottawa, Jan. 1968. (NRC 9768).

3 . Blanchard, J. A. C. and

T.

Z. Harmathy. S m a l l - s c a l e f i r e t e s t

f a c i l i t i e s of the National R e s e a r c h Council of Canada, Division of Building R e s e a r c h . F i r e Study No. 14, Ottawa, Nov. 1964. (NRC 8207).

4. F i r e t e s t s of building construction and m a t e r i a l s , ASTM Designation E l 19-61. A m e r i c a n Society f o r Testing and M a t e r i a l s

.

Philadelphia, P a .

5. Robertson, A. F. and J. V. Ryan. P r o p o s e d c r i t e r i a f o r defining load f a i l u r e of b e a m s , f l o o r s and roof construction during f i r e t e s t . J o u r n a l of R e s e a r c h . National B u r e a u of Standards, 63C, Washington, 1959, p. 121

-

124.

6. Stanzak, W. W. F i r e t e s t s on wide-flange s t e e l b e a m s p r o t e c t e d with gypsum- sanded p l a s t e r . National R e s e a r c h

Council of Canada, Division of Building R e s e a r c h . F i r e Study No. 16, Ottawa, M a r c h 1967. (NRC 9474).

7. M i n e r a l wool t h e r m a l building insulation. CSA Standard A 101

-

1968. Canadian S t a n d a r d s Association, Ottawa, Ont.

8. Methods of f i r e t e s t s of walls, partitions, f l o o r s , roofs,

ceilings, columns, b e a m s and g i r d e r s . CSA Standard B54.3

-

19 64. Canadian S t a n d a r d s Association, Ottawa, Ont.

FIGURE I

CONSTRUCTION DETAILS OF SPECIMEN USED IN BEAM TEST

B R . 4010-/

Figure 2. Exposed

surface before fire test.

Figure 3. Unexposed

surface before fire test.

F I G U R E 4 T H E R M O C O U P L E L O C A T I O N S

1500

Sheet Steel Membrane, Test 1

Beam o f C S A 640. 12 Steel ( A v g : 7, 8, 11, 12, 16 LL 1000 0 W w =2 C a D Z W n I 500 I 0 30 60 9 0 120 TI ME, MINUTES

FIGURE 5 BEAM TEMPERATURES

I

I

I

I

A d d 0. 75 i n . f o r S t a t i c D e f l e c t i o n

-

-

- -

6;

i c r i t )

=

0 . 4 8 i n . ~ m i n

-

-

-

. ' O -

1

I

I

1

0

10

20

3 0

40

50

6 0

7 0

80

90

100

110

T I M E , M I N U T E S

F I G U R E 6

D E F L E C T I O N A N D R A T E O F D E F L E C T I O N

BR 4010- 4

FIGURE

7

CONSTRUCTION DETAILS OF SPECIMENS USED IN COLUMN TESTS

Figure

8.

Columns under

= I construction.

Figure

9.

Column No. 2 completed.

DISTANCE FROM THE

BOTTOM PLATE

LEVEL

3, 2 FT

1'14

IN.

LEVEL 2 , 4 FT

1114

IN.

LEVEL

I

,

6 FT

1114

IN.

FIGURE

10

LOCATION

OF

THERMOCOUPLES

EAST

_-

THERMOCOUPLE JUNCTION

FIGURE

II

F U R N A C E T H E R M O C O U P L E LOCATIONS

B R 4026 - 2

Figure 14.

Column No.

1 partly dismantled after fire test.

Figure 15. Column

No.

2 after I

fire test.

Figure

16.

Column No. 2 with steel cover removed after f i r e test.

Figure 17. Column No. 2: insulation joint after test.

TIME, MINUTES