Leakage and bond strength tests on small panels containing low suction extruded bricks and cement-lime mortars

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Leakage and bond strength tests on small panels containing low

suction extruded bricks and cement-lime mortars

NATIONAL RESEARCH COUNCIL O F CANADA DIVISION O F BUILDING RESEARCH

LEAKAGE AND BOND STRENGTH TESTS ON SMALL PANELS CONTAINING LOW SUCTION EXTRUDED BRICKS

AND CEMENT-LIME MORTARS

I n t e r n a l R e p o r t No.

349

of the

Division of Building R e s e a r c h

OTTAWA

P R E F A C E

T h i s r e p o r t i s a continuation of the study included in DBR I n t e r n a l R e p o r t 270 in which s e a s o n a l effects on the curing of l i m e m o r t a r w e r e a s s e s s e d .

The expanded p r o g r a m , now r e p o r t e d , included four c e m e n t - l i m e m o r t a r s in which p r o g r e s s i v e l y l a r g e r amounts of P o r t l a n d cement r e p l a c e d equivalent volumes of the l i m e in the original m o r t a r .

It

a l s o provided a n opportunity t o c o m p a r e (1) l a b o r a t o r y and exposure s i t e curing with ( 2 ) the compatibility of the low suction b r i c k extensively used in the a r e a with the v a r i o u s m o r t a r combinations.

The work, c a r r i e d out a t the Atlantic Regional Station of the Division in Halifax, r e f l e c t s the continual effort t o c o r r e l a t e l a b o r a t o r y and field conditions.

The author i s a c h e m i s t and a r e s e a r c h officer

with the Division, engaged in studies of m a s o n r y p e r f o r m a n c e in the Atlantic P r o v i n c e s .

Ottawa August 1967

R o b e r t F. Legget D i r e c t o r

L E A K A G E A N D B O N D S T R E N G T H T E S T S O N S M A L L PANELS CONTAINING LOW SUCTION EXTRUDED BRICKS

AND CEMENT-LIME MORTARS

J . I. Davison

At the conclusion of an e a r l i e r study of s m a l l panels containing low suction extruded b r i c k s and l i m e m o r t a r (DBR I n t e r n a l R e p o r t No. 270) i t was decided t o extend the p r o g r a m t o include m o r t a r s in which the l i m e content was p r o g r e s s i v e l y replaced by portland cement. The purpose of the original study was t o d e t e r m i n e the effect, i f any, of the s e a s o n a l v a r i a t i o n s in weather on the curing of the m o r t a r used in the panels.

At i n t e r v a l s of one month, a s e t of panels was a s s e m b l e d (two identical panels, one being c u r e d on an outdoor exposure s i t e and the other a control panel in l a b o r a t o r y a i r at 7 0 ° F and

50 p e r cent RH). P a n e l s w e r e a s s e s s e d on the b a s i s of r e s u l t s f r o m leakage and bond s t r e n g t h t e s t s conducted a f t e r a s i x -

month curing period. In the extended p r o g r a m , 192 panels containing 1:3:12, 1:2:9, 1:1:6 and 1:$:3 c e m e n t - l i m e m o r t a r s w e r e a s s e m b l e d between November 1961 and M a r c h 1966.

F i n a l t e s t s w e r e completed in October 1966. MATERIALS

A solid extruded b r i c k having a n IRA range 0.4 t o

4 . 1 g m p e r 30 s q in. p e r min was used throughout the p r o g r a m with two exceptions

-

four panels in the 1:2:9 c e m e n t - l i m e m o r t a r s e r i e s contained a solid extruded b r i c k with an IRA range 4.7 t o 8 . 0 g m p e r 30 s q in. p e r min, and the final 28

panels in the s e r i e s , of 1:$3 c e m e n t - l i m e m o r t a r , contained another solid, extruded b r i c k vyith a n IRA r a n g e 1 . 1 t o 2.9 g m p e r 30 s q in. p e r min. The t h r e e b r i c k s c a m e f r o m t h r e e different plants. The m o r t a r contained a high c a l c i u m l i m e putty obtained locally, M a r i t i m e Brand P o r t l a n d cement, and Shubenacadie sand, the l a t t e r a pit sand t h a t e i t h e r m e t o r c a m e c l o s e t o meeting t h e grading r e q u i r e m e n t s of CSA Specification A82.56, Aggregate f o r Masonry Mortar.

METHOD

The s m a l l panels contained 5 b r i c k s with 4 m o r t a r joints. The p r o c e d u r e s f o r panel a s s e m b l y , leakage and bond

s t r e n g t h t e s t s w e r e d e s c r i b e d in the r e p o r t on t h e previous study (IR 270). Outdoor curing took place on an exposure site on t h e roof of the Atlantic Regional L a b o r a t o r y building. P a n e l s w e r e housed i n wooden s h e l t e r s i n such a way t h a t

only one f a c e , oriented t o the south, was exposed t o the weather. 1:3:12 Cement-Lime M o r t a r P a n e l s

F o r t y - f o u r panels w e r e a s s e m b l e d between November 1961 and F e b r u a r y 1963. E a c h batch of m o r t a r contained 110. 3 g m of portland cement, 311.7 g m of l i m e putty, and 1607 g m of sand. T h e s e f i g u r e s w e r e calculated on the b a s i s of l a b o r a t o r y density determinations on the l i m e putty and

sand, and using 87. 5 pounds p e r cubic foot f o r portland cement. Sufficient w a t e r was added t o produce the r e q u i r e d m o r t a r flow, The f i r s t eight s e t s of panels, and a l l succeeding

even-numbered panels contained m o r t a r a t 110 p e r cent (low), while panel EXP9 and s u c c e s s i v e odd-numbered panels con- tained m o r t a r a t 125 p e r cent flow (high). The b r i c k s used w e r e in the IRA range 0.4 t o 4 . 1 g m p e r 30 s q in. p e r min. Low flow m o r t a r panels w e r e a s s e m b l e d with a 30-second t i m e i n t e r v a l between the laying of the m o r t a r bed and the placing of the top b r i c k , accompanied by a "heavy" t a p ( a four-pound weight dropped through 1 i in c h e s ) . A 60-

second t i m e i n t e r v a l and a "light" t a p (two-pound weight dropped through l i i n c h e s ) w e r e u s e d in a s s e m b l i n g panels containing high flow m o r t a r .

Average m o i s t u r e content values f o r m o r t a r s and a v e r a g e weights of m o r t a r used in panels w e r e a s follows:

Average Moisture Average Wt of Content (70) M o r t a r ( g m ) 11070 flow m o r t a r 16.8 1146

125% flow m o r t a r 1 7 . 4 1219 CURING

During the curing p e r i o d seven panels w e r e broken and a breakdown c l a s s i f i e s t h e m a s follows:

( a ) Low flow m o r t a r , exposure c u r e d

-

3 of 1 5 panels broken;

( b ) Low flow m o r t a r , control

-

1 of 1 5 panels broken; ( c ) High flow m o r t a r , exposure c u r e d

-

2 of 7 panels

broken;

( d ) High flow m o r t a r , control

-

1 of 7 panels broken. In addition to the broken panels, four other exposure c u r e d panels l o s t one b r i c k , but since i t was e i t h e r the top o r bottom b r i c k , they w e r e t e s t e d a s f o u r - b r i c k panels. L o s s and/or damage of 11 panels during the curing p e r i o d reflected the

inability of the l o w - s t r e n g t h m o r t a r joints t o withstand handling. It should a l s o be noted that s e v e r a l of the panels w e r e broken on the exposure site when they toppled over during a s e v e r e s t o r m .

The d a t a indicated that panels containing low flow m o r t a r and c u r e d in the l a b o r a t o r y p e r f o r m e d b e s t during leakage t e s t s . Control p a n e l s w e r e a l s o b e t t e r than e x p o s u r e c u r e d panels when high flow m o r t a r s w e r e used.

LEAKAGE

R e s u l t s of leakage t e s t s a r e shown in detail in Table I and s u m m a r i z e d a s follows:

In the panels w h e r e leakage o c c u r r e d , the p a t t e r n was quite uniform. Leakage s t a r t e d e a r l y in the t e s t , gradually d e c r e a s e d , and finally stopped. In panels with slight leakage, w a t e r w a s o b s e r v e d on the back of the m o r t a r joints, but l a t e r d r i e d up b e f o r e enough accumulated t o r u n off t h e panel in a m e a s u r a b l e quantity.

The weight changes in the panels during the curing period and leakage t e s t w e r e interesting. The f o r m e r r e p r e s e n t e d the amount of w a t e r l o s t o r gained by the panel while c u r i n g , while the l a t t e r r e p r e s e n t e d the amount of w a t e r that e n t e r e d the panel during the leakage t e s t . The f i g u r e s indicated that c o n t r o l panels l o s t substantially m o r e weight during curing than those on the e x p o s u r e s i t e . This

No. of P a n e l s with NO Leakage 6 10 0 3 No. of P a n e l s with Slight Leakage 5 4 5 0 Wt P i c k - u p During Leakage T e s t 167 g m 231 g m 207 g m 262 g m No. of P a n e l s with Measurable Leakage 1 0 0 3 No. of P a n e l s T e s t e d 12 14 5

6

I

W t M o r t a r Flow and P a n e l Change During Curing Designation P e r i o d ~ o w / e x ~ o s u r e

1-

24 g m ~ o w / c o n t r o l ~ i ~ h / e x ~ o s u r e ~ i ~ h / c o n t r o l -155 g m

+

18 g m -186 g m

was predictable because the l a t t e r w e r e exposed t o variable weather conditions and w e r e not d r i e d t o a u n i f o r m condition before weight changes w e r e determined. Thus, they r e f l e c t e d weather conditions during the curing period and those just before t h e i r r e m o v a l f r o m the exposure s i t e . On the other hand, the f i g u r e s f o r the control panels w e r e proportionately m o r e significant since t h e y w e r e exposed f o r 6 months under constant conditions at 7 0 ° F and 50 p e r cent r e l a t i v e humidity. T h i s m a d e i t understandable t h a t t h e d r i e r control panels a b s o r b e d m o r e w a t e r during leakage t e s t s .

BOND STRENGTH

One panel was broken a f t e r leakage t e s t i n g , leaving 36 panels f o r bond strength t e s t s . F r o m the 144 joints in t h e s e panels, 11 2 values w e r e obtained. The additional 32 joints f o r which no values w e r e obtained r e p r e s e n t e d 8 panels. This meant that of the original 44 panels, 16 did not survive completion of leakage and bond s t r e n g t h t e s t s . T h i s substantial l o s s of panels suggested l a c k of s t r e n g t h in the bond between b r i c k and m o r t a r and t h i s w a s supported in the following s u m m a r y of bond s t r e n g t h values:

Low flow m o r t a r panels exposure c u r e d 14.8 p s i 41 values Low flow m o r t a r panels control 11. 5 p s i 43 values High flow m o r t a r panels exposure c u r e d 16.2 p s i 14 values High flow m o r t a r panels control 5. 5 p s i 14 values

The highest individual value, 31.0 p s i , was obtained in a high flow m o r t a r exposure c u r e d panel a s s e m b l e d in August. Highest individual value f o r a low flow m o r t a r ,

29.6 p s i , w a s obtained f r o m a n e x p o s u r e c u r e d panel a s s e m b l e d in A p r i l . The s a m e panel a l s o produced the highest a v e r a g e values ( 4 joints), 26.9 p s i f o r the s e r i e s . Bond s t r e n g t h values f o r e x p o s u r e c u r e d panels w e r e higher than those f o r c o n t r o l panels with b e s t values coming f r o m high flow m o r t a r e x p o s u r e c u r e d panels.

Visual o b s e r v a t i o n of the f r a c t u r e d m o r t a r joints r e v e a l e d that b r e a k s o c c u r r e d in 50 i n s t a n c e s with the top b r i c k lifting cleanly f r o m the m o r t a r bed. In t h i s type of b r e a k t h e r e was l i t t l e evidence of bond between the b r i c k and m o r t a r , and bond s t r e n g t h v a l u e s w e r e low. Twenty- t h r e e joints f r a c t u r e d with a "shattering" of the m o r t a r bed, s o m e of which r e m a i n e d bonded t o e a c h of t h e two b r i c k s . The r e m a i n i n g 39 f r a c t u r e s r e s u l t e d f r o m a b r e a k through

the m o r t a r bed. Both of the l a t t e r types of f r a c t u r e w e r e a s s o c i a t e d with good values and an excellent extent of bond. Observation of the m o r t a r bed f r o m f r a c t u r e d ~ o i n t s r e v e a l e d a distinct p e r i m e t e r band of carbonated m o r t a r . The band was wider in control panels than in those c u r e d on e x p o s u r e , but the n a r r o w e r (3/4 inch v e r s u s 1 inch f o r control p a n e l s ) carbonation band in the exposure c u r e d panels was m o r e "intense" in colour, a s though t h e r e had been a g r e a t e r amount of carbonation in the band. This m a y explain the higher bond s t r e n g t h values obtained f r o m exposure c u r e d panels despite the apparent l e s s e r extent of the carbonation band.

SEASONAL E F F E C T

Examination of data and of g r a p h s 1 t o 3 did not

indicate any definite p a t t e r n a s a r e s u l t of the weather during the curing period. T h e r e was some indication of higher bond s t r e n g t h values f o r panels a s s e m b l e d in the F e b r u a r y

-

S e p t e m b e r period and c u r e d during the spring

-

s u m m e r

-

f a l l period.

1:2:9 C e m e n t - L i m e M o r t a r P a n e l s

F o r t y - e i g h t panels w e r e a s s e m b l e d in t h i s group

between M a r c h 1963 and F e b r u a r y 1964. E a c h batch of m o r t a r contained 147. 1 g m of portland cement, 281. 0 g m of l i m e

putty, and 1607.8 g m of sand. Extruded b r i c k s in the IRA r a n g e 1.0 t o 4 . 1 g m p e r 30 s q in. p e r min w e r e u s e d f o r a l l panels except the two s e t s a s s a m b l e d in August, when an extruded b r i c k with an IRA r a n g e 4.7 t o 8 . 0 g m p e r 30 s q in.per min w a s used. Two s e t s of panels w e r e a s s e m b l e d e a c h month, one s e t with low flow ( 1 10 p e r cent) m o r t a r and the other with high flow (125 p e r cent). Conditions of panel a s s e m b l y w e r e a s outlined f o r the previous s e r i e s . Average m o i s t u r e content and a v e r a g e weights of m o r t a r u s e d in the panels w e r e a s follows:

Average Moisture Average Wt of Content (70) M o r t a r (gm) 11070 flow m o r t a r 16. 6 1243

125% flow m o r t a r 17. 5 1302 CURING

Only one panel was broken during the curing period, a panel containing high flow m o r t a r on the exposure site. One other panel containing low flow m o r t a r and c u r e d on e x p o s u r e l o s t one b r i c k , but was t e s t e d a s a f o u r - b r i c k panel

LEAKAGE

Data f r o m leakage t e s t s a r e compiled in Table

I1

and s u m m a r i z e d a s follows: No. of P a n e l s with Slight Leakage No. of P a n e l s with Measurable Leakage 0 0 2 1 M o r t a r Flow and P a n e l Designation ~ o w / e x ~ o s u r e ~ o w / c o n t r o l ~ i ~ h / e x ~ o s u r e ~ i ~ h / c o n t r o l

The only m e a s u r a b l e leakage o c c u r r e d in t h r e e panels containing high flow m o r t a r , one a control panel and two c u r e d on exposure. Slight leakage was r e c o r d e d in a high flow m o r t a r exposure c u r e d panel and a low flow m o r t a r panel a l s o c u r e d on exposure. T h e s e low flow m o r t a r panels again p e r f o r m e d b e s t during leakage t e s t s . Wt Change During Curing P e r i o d

-

1 g m -190 g m

-

46 g m -213 g m

The t h r e e panels that leaked r e c o r d e d s m a l l t o t a l s a t 10, 5, and 20 ml. The s a m e p a t t e r n was o b s e r v e d in a l l p a n e l s in which t h e r e was no leakage: a t the end of the t e s t p e r i o d m o r t a r joints w e r e d a r k , but d r y t o touch. As i n the previous s e r i e s , the d r i e r control panels a b s o r b e d m o r e w a t e r (about 100 g m ) during the t e s t period than those c u r e d on the exposure site. The a v e r a g e values f o r high and low

No. of P a n e l s T e s t e d 12 12 11 12

flow m o r t a r s w e r e r e m a r k a b l y consistent. Weight l o s s e s during the curing period followed the s a m e p a t t e r n , but t h e y w e r e not a s consistent a s those f o r w a t e r pick-up. It was obvious f r o m r e s u l t s f o r the f i r s t two s e r i e s that the amount of w a t e r a b s o r b e d by tight panels during the leakage t e s t s was r e l a t e d t o the ability of t h e m o r t a r t o a b s o r b w a t e r a t the t i m e of the t e s t .

BOND STRENGTH

F o r t y - s e v e n panels w e r e t e s t e d and a t o t a l of 180 values obtained f r o m 187 joints (one panel had t h r e e joints). Average bond s t r e n g t h values were:

Low flow m o r t a r panels e x p o s u r e c u r e d 23.6 p s i 46 values Low flow m o r t a r p a n e l s c o n t r o l 15. 3 p s i 46 values High flow m o r t a r p a n e l s e x p o s u r e c u r e d 23.1 p s i 41 values High flow m o r t a r p a n e l s c o n t r o l 13. 5 p s i 47 values

The highest individual value (46.3 p s i ) o c c u r r e d in a high flow m o r t a r exposure c u r e d panel. This was closely followed by a 4 5 . 3 p s i value f o r a low flow m o r t a r exposure c u r e d panel. The b e s t a v e r a g e value f o r a panel ( 4 joints)

-

33. 5 p s i

-

o c c u r r e d in a low flow m o r t a r panel c u r e d on exposure. T h i s panel contained b r i c k s in the 4.7 t o 8 . 0 g m p e r 30 s q in. p e r min suction range. The highest a v e r a g e value f o r a panel of the lower suction b r i c k s was 32.0 psi, and it contained

high flow m o r t a r and was exposure cured. Again the s u p e r i o r i t y of values f o r exposure c u r e d panels over control panels was c l e a r l y indicated. Variation in flow of the m o r t a r did not have a s g r e a t an effect on bond s t r e n g t h values, although values f o r low flow m o r t a r panels w e r e slightly higher than those f o r high flow.

The p a t t e r n indicated by visual observation of f r a c t u r e d joints was a s follows:

( a ) Top b r i c k lifted cleanly f r o m m o r t a r bed

-

84 joints; ( b ) Top b r i c k lifted; some m o r t a r stuck t o top b r i c k

-

76 joints;

( c ) B r e a k through m o r t a r bed

-

20 joints.

Most f r a c t u r e s o c c u r r e d when the top b r i c k lifted f r o m the m o r t a r bed. When the b r e a k was clean t h e r e w e r e usually low values. When s o m e of the m o r t a r r e m a i n e d on the top b r i c k , the bond s t r e n g t h values w e r e higher. B e s t values w e r e a s s o c i a t e d with joints w h e r e b r e a k s o c c u r r e d through the m o r t a r beds.

SEASONAL E F F E C T

Examination of d a t a and of G r a p h s 4 t o 6 again did not indicate a d e c i s i v e p a t t e r n a s a r e s u l t of s e a s o n a l weather during the curing period, although slightly higher bond strength values w e r e obtained f r o m panels a s s e m b l e d in the July

-

November period and c u r e d during the f a l l and winter months. 1: 1:6 C e m e n t - L i m e M o r t a r P a n e l s

F o r t y - e i g h t panels w e r e a s s e m b l e d using t h i s m o r t a r between M a r c h 1964 and F e b r u a r y 1965. E a c h batch of

m o r t a r contained 220.7 g m of P o r t l a n d cement, 211.1 g m of l i m e putty, and 1607 g m of sand. Low suction extruded b r i c k s in IRA r a n g e 0 . 4 t o 3 . 3 g m p e r 30 s q in. p e r min w e r e used. Again two s e t s of panels, one with low flow (110 p e r c e n t ) , and the other high flow (125 p e r cent) m o r t a r w e r e a s s e m b l e d e a c h month. Conditions of panel a s s e m b l y r e m a i n e d the s a m e . Average m o i s t u r e content values f o r m o r t a r s and a v e r a g e weights of m o r t a r s u s e d in panels w e r e a s follows:

Average M o i s t u r e Average Wt of Content

(70)

M o r t a r ( g m )

110% flow m o r t a r 15. 2 1261

125% flow m o r t a r 16.2 1270

CURING

Data on leakage t e s t s i s compiled i n d e t a i l in T a b l e

111 and s u m m a r i z e d a s follows: M o r t a r Flow and P a n e l Designation ~ o w / e x ~ o s u r e ~ o w / c o n t r o l High/exposure High/control Wt P i c k - u p During L e a k a g e T e s t t 1 3 4 g m 1-226 g m f 147 g m t 2 2 7 g m No. of P a n e l s with No. of P a n e l s with M e a s u r a b l e Leakage 0 0 1 1 Wt Change During Curing P e r i o d

-

21 g m - 1 4 8 g m - 5 5 g m -168 g m

T h r e e of the four panels i n which m e a s u r a b l e o r slight leakage o c c u r r e d contained high flow m o r t a r and two w e r e c u r e d on e x p o s u r e . The g r e a t e s t amount of l e a k a g e , 114 m l , o c c u r r e d i n a high flow m o r t a r e x p o s u r e c u r e d panel. Leakage began

soon a f t e r the t e s t began and, unlike the p a t t e r n i n previous s e r i e s , i t continued until the end. In another panel of high flow m o r t a r c u r e d u n d e r c o n t r o l conditions, 1 8 - m l leakage s t a r t e d 6 h o u r s a f t e r the t e s t w a s initiated and w a s a t t r i b u t e d t o a s m a l l c r a c k i n the bottom b r i c k . Slight leakage o c c u r r i n g in a low flow m o r t a r c o n t r o l panel was a l s o attributed t o a defective b r i c k .

No. of P a n e l s No. of P a n e l s T e s t e d 12 12 12 12

At the end of the l e a k a g e t e s t p e r i o d s , a l l other p a n e l s h a d d a r k joints but w e r e d r y t o touch. The change in colour i n m o r t a r joints r e f l e c t e d the absorption of w a t e r during the t e s t . The " d r i e r " control p a n e l s followed the p a t t e r n of

p r e v i o u s s e r i e s by absorbing m o r e w a t e r than exposure c u r e d panels d u r i n g leakage t e s t s

-

a n a v e r a g e of 8 5 gm. Like the 1:2:9 c e m e n t - l i m e m o r t a r p a n e l s , the amount of w a t e r a b s o r b e d f o r e x p o s u r e and c o n t r o l panels w a s quite c o n s i s t e n t , high flow m o r t a r p a n e l s absorbing only a v e r y s m a l l amount m o r e than low flow m o r t a r p a n e l s .

BOND STRENGTH

All 48 p a n e l s (one with four b r i c k s ) w e r e t e s t e d f o r bond s t r e n g t h and 187 values w e r e obtained f o r the 191 joints. A v e r a g e values w e r e :

Low flow m o r t a r panels exposure c u r e d 42.2 p s i 47 values Low flow m o r t a r panels control 33. 0 p s i 47 values High flow m o r t a r panels exposure c u r e d 47.2 p s i 46 values High flow m o r t a r panels control 35.4 p s i 47 values The two highest individual values, 93.9 and 88.6 p s i , o c c u r r e d in a high flow m o r t a r exposure c u r e d panel. Highest a v e r a g e value f o r a panel ( 4 values) a t 68.4 p s i a l s o o c c u r r e d in t h i s panel. Highest a v e r a g e values w e r e r e c o r d e d f o r panels on high flow m o r t a r c u r e d on exposure. E x p o s u r e c u r e d panels containing low flow m o r t a r a l s o had higher values than control panels.

Visual observation indicated the followillg p a t t e r n f o r f r a c t u r e d joints.

( a ) Top b r i c k lifted cleanly f r o m m o r t a r bed

-

95 joints;

( b ) Top b r i c k lifted; s o m e m o r t a r stuck to top b r i c k

-

55 joints;

( c ) B r e a k s through m o r t a r bed

-

37 joints.

Most f r a c t u r e s again o c c u r r e d with the top b r i c k lifting f r o m the m o r t a r bed. This type of b r e a k , however, was not

n e c e s s a r i l y indicative of low values and a poor extent of bond. T h e r e w e r e , in f a c t , s o m e excellent values and a good extent of bond. But on the a v e r a g e , the b e t t e r values continued t o be a s s o c i a t e d with b r e a k s in which some m o r t a r stuck t o the top b r i c k o r where the f r a c t u r e was through the m o r t a r bed. The two top individual values mentioned above o c c u r r e d with f r a c t u r e s of the l a t t e r type.

SEASONAL E F F E C T

Data and g r a p h s 7 t o

9

did not indicate any p a t t e r n r e s u l t i n g f r o m v a r i a t i o n s in s e a s o n a l w e a t h e r during the curing period. Slightly higher bond s t r e n g t h values o c c u r r e d in panels a s s e m b l e d between October and F e b r u a r y

and c u r e d during the winter and spring period. 1:5:3 C e m e n t - L i m e M o r t a r P a n e l s

Fifty-two panels w e r e a s s e m b l e d between M a r c h 1965 and M a r c h 1966. E a c h batch of m o r t a r contained 441.3 g m of portland cement, 103.9 g m of l i m e putty, and 1608 g m of sand. E x t r u d e d b r i c k with a n IRA r a n g e 0.9 t o 2.9 g m p e r 30 s q in. p e r min was u s e d in the f i r s t 24 panels, and another extruded b r i c k with a n IRA r a n g e 1 . 1 t o 2.9 g m p e r 30 s q in. p e r min w a s u s e d in the l a s t 28 panels. Again, two s e t s of panels w e r e a s s e m b l e d a t monthly i n t e r v a l s , one s e t with

a low flow m o r t a r and the other with a high flow m o r t a r . S e v e r a l flow values w e r e used in this s e r i e s , however, a s indicated below: ( a ) P a n e l s a s s e m b l e d 110 p e r cent 1 s e t M a r c h 1965 flow m o r t a r ( b ) P a n e l s a s s e m b l e d 125 p e r cent 7 s e t s A p r i l t o October flow m o r t a r 1965 inclusive ( c ) P a n e l s a s s e m b l e d 135 p e r cent 13 s e t s M a r c h 1965 t o flow m o r t a r M a r c h 1966 inclusive ( d ) P a n e l s a s s e m b l e d 145 p e r cent 5 s e t s November 1965 flow m o r t a r t o M a r c h 1966 inclusive

Thus, the t e r m s "low" and "high" do not b e a r the s a m e signi- f i c a n c e a s they did in the previous s e r i e s .

As the flow values w e r e a l t e r e d , s o w e r e the conditions of panel a s s e m b l y . In g e n e r a l , the low flow m o r t a r panels w e r e a s s e m b l e d with a 30-second t i m e i n t e r v a l and a heavy tap, and high flow m o r t a r panels with a 60-second t i m e i n t e r v a l

and a light tap. Thus, 110 and 125 p e r cent flow m o r t a r s w e r e a s s o c i a t e d with the 30-second i n t e r v a l and a heavy tap, a s w e r e the 135 p e r cent flow m o r t a r panels a f t e r they

b e c a m e "low" flow in the period November 1965 t o M a r c h 1966 inclusive. The 135 p e r cent flow m o r t a r panels in the M a r c h

-

October 1965 period and the 145 p e r cent flow m o r t a r p a n e l s w e r e a s s e m b l e d with a 60-second i n t e r v a l and a

light tap.

Average m o i s t u r e content values f o r m o r t a r s and a v e r a g e weights of m o r t a r u s e d in panels w e r e a s follows:

Average Moisture Average Wt of Content

(70)

M o r t a r ( g m ) 11 0% flow m o r t a r 14. 0 1248 125% flow m o r t a r a 13.9 1278 135% flow m o r t a r b 1 4 . 4 1279 135% flow m o r t a r 14.4 1349 14570 flow m o r t d r 15,O 1398 a

b P a n e l 6 a ~ , r ; r m b l c d wlth 60 sccond t i m c i n t c r v a l and light tap. P a n e l s a s s e m b l e d with 30-second t i m e i n t e r v a l and heavy tap.

CURING

Eight panels w e r e broken during the curing period, and, in view of the n u m e r o u s v a r i a b l e s in t h i s group, the l o s s e s w e r e s u m m a r i z e d f o r study:

110% flow m o r t a r control 1 panel broken

125% flow m o r t a r exposure c u r e d 1 panel broken 125% flow m o r t a r

b control 1 panel broken

135% flow m o r t a r

b control 2 panels broken

135% flow m o r t a r exposure c u r e d 1 panel broken

145% flow m o r t a r control 2 panels broken

None of the panels containing 135 p e r cent flow m o r t a r a s s e m b l e d with a 30-second i n t e r v a l and a heavy t a p w e r e broken p r i o r t o leakage t e s t s . It was a l s o noted that s i x of the eight panels broken w e r e control panels. The l o s s of panels in t h i s group was

attributed t o t h e i r b r i t t l e n e s s r a t h e r than t o l a c k of strength, a s in the c a s e of the panels containing 1:3:12 c e m e n t - l i m e m o r t a r .

LEAKAGE

Data f r o m leakage t e s t s i s compiled in d e t a i l in Table I V and s u m m a r i z e d a s follows:

Wt No. of No. of W t

Change P a n e l s P a n e l s No. of P i c k - u p M o r t a r Flow During No. of with with P a n e l s During

and P a n e l Curing P a n e l s Measurable Slight with No Leakage Designation P e r i o d T e s t e d Leakage Leakage Leakage T e s t

110% exposure i- 1 5 g m 1 0 1 0 t l l 6 g m 110% control

-

- - -

- - -

- - -

- - -

- - -

- -

- - -

125% exposure

+

12 g m

6

0 1 5 f 7 9 g m 125% control _a -101 g m 6 0 0 6 t l O l g m 135% exposure f 6 g m 6 a 0 1 5 t 7 5 g m 135% control - 1 0 7 g m 6 0 0 6 t 1 1 5 g-m 135% exposu e

_b

-

49 g m 6 0 0 6 t 56 g m 135% control -117 g m 5 0 0 5 t 1 1 5 g m 145% e x p o s u r e

-

53 g m 5 0 0 5 f 60 gin 145% control -120 g m 3 0 0 3 t 1 1 3 g m a

b P a n e l s a s s e m b l e d with 60-second t i m e i n t e r v a l and light tap. P a n e l s a s s e m b l e d with 30-second t i m e i n t e r v a l and heavy tap.

T h e r e w a s no m e a s u r a b l e leakage through any of the panels i n t h i s s e r i e s , Slight leakage o c c u r r e d in t h r e e p a n e l s , a l l a s s e m b l e d during the l a t e winter months ( M a r c h and A p r i l ) and c u r e d on exposure.

Visual observations of the b a c k s of the panels t h a t did not l e a k during the t e s t s revealed s o m e d i f f e r e n c e s . E l e v e n of the panels had the u s u a l d a r k m o r t a r joints a t the end of the t e s t , which indicated water absorption. Twelve panels had slightly discoloured ( g r e y ) joints, four showed no discolouration, and the remaining p a n e l s had s o m e p e r - centage of t h e i r joints darkened. T h e r e w a s no p a r t i c u l a r p a t t e r n on the b a s i s of the v a r i a b l e s in flow, curing and con- ditions of a s s e m b l y . The reduction in the discolouration of the m o r t a r joints a p p e a r e d t o have r e s u l t e d f r o m the reduced p e r m e a b i l i t y of the d e n s e r m o r t a r .

F i g u r e s f o r weight changes during the curing p e r i o d s and leakage t e s t s w e r e a l s o reduced f r o m the previous s e r i e s . The reduction in w a t e r absorption supported the a s s u m p t i o n of reduced p e r m e a b i l i t y of t h i s m o r t a r combination. In a c c o r d a n c e with the p a t t e r n i n p r e v i o u s s e r i e s , the w a t e r a b s o r b e d was higher f o r control panels than f o r e x p o s u r e panels and t h e r e w a s no significant difference in t o t a l s f o r high- and low-flow m o r t a r s and in v a r i a t i o n s in panel a s s e m b l y techniques.

BOND STRENGTH

F o r t y - f o u r p a n e l s w e r e t e s t e d and 144 values w e r e obtained f r o m the 176 joints. R e s u l t s w e r e a s follows:

Average 110% flow m o r t a r

-

e x p o s u r e c u r e d 1 l O % f l o w m o r t a r

-

c o n t r o l 125% flow m o r t a r

-

e x p o s u r e c u r e d 125% flow m o r t a r

-

c o n t r o l a 135% flow m o r t a r

-

e x p o s u r e c u r e d a 135% flow m o r t a r

-

c o n t r o l b 135% flow m o r t a r _b

-

e x p o s u r e c u r e d 135% flow m o r t a r

-

c o n t r o l 145% flow m o r t a r

-

e x p o s u r e c u r e d 145% flow m o r t a r

-

c o n t r o l 37.0 p s i 37.4 p s i

-

- -

- - - -

- - -

45.0 p s i 9 4 . 3 p s i 3 7 . 9 p s i 9 7 . 3 p s i 42.2 p s i 104.6 p s i 4 2 . 4 p s i 8 1 . 5 p s i 32.6 p s i 70. 5 p s i 20. 5 p s i 50. 5 p s i 28. 1 p s i 51.0 p s i 2 4 . 0 p s i 1 1 . 9 p s i a

b P a n e l s a s s e m b l e d with 60-second t i m e i n t e r v a l and light tap. P a n e l s a s s e m b l e d with 60-second t i m e i n t e r v a l and heavy tap.

The highest individual values, 104. 6 and 97.9 psi, o c c u r r e d in panels containing 135 p e r cent flow m o r t a r a s s e m b l e d

with a 60-second i n t e r v a l and a light tap, and c u r e d on exposure. The highest a v e r a g e value f o r a panel ( 4 joints) was 68.4 p s i in a control panel which contained a 135 p e r cent flow m o r t a r , and a s s e m b l e d with a 60-second i n t e r v a l and a light tap.

The added v a r i a b l e s in this s e r i e s make meaningful c o m p a r i s o n s difficult. The r e s u l t s c l e a r l y indicate, however, the s u p e r i o r i t y

of exposure panels over control panels. It i s a l s o indicated that highest a v e r a g e values o c c u r r e d in panels of the f i r s t extruded b r i c k and m o r t a r s having 125 and 135 p e r cent flow, t h e f o r m e r a s s e m b l e d with a 30-second t i m e i n t e r v a l and a heavy t a p and the l a t t e r with a 60-second i n t e r v a l and a light tap. Lower bond s t r e n g t h values f o r panels containing the second extruded b r i c k and 135 p e r cent flow m o r t a r could have r e s u l t e d f r o m

(1)

the difference in b r i c k s and/or ( 2 ) change i n conditions of a s s e m b l y whereby the 60-second i n t e r v a l and light t a p r e p l a c e d the s h o r t e r t i m e and heavier t a p used with b r i c k No. 1 and the 135 p e r cent flow m o r t a r . As noted previously, panels in t h i s s e r i e s w e r e v e r y b r i t t l e , which m a y account f o r l o s s of a number through

breaking during the curing period. The o c c u r r e n c e of n u m e r o u s i n f e r i o r bond s t r e n g t h values and complete l o s s of o t h e r s was thought t o be due t o the effect of the r e c o i l in the panel when

strong joints w e r e f r a c t u r e d .

The p a t t e r n o b s e r v e d in f r a c t u r e d joints was a s follows:

Top B r i c k Lifted B r e a k - T h r o u g h Cleanly With M o r t a r Clinging M o r t a r Bed 110% flow 2 125% flow 30 135%; flow 28 135% flow 33 145% flow 25 a

b P a n e l s a s s e m b l e d with 60-second t i m e i n t e r v a l and light tap. P a n e l s a s s e m b l e d with 30-second t i m e i n t e r v a l and heavy tap. F r a c t u r e s again o c c u r r e d p r i m a r i l y when the top b r i c k pulled away f r o m the m o r t a r bed, and t h i s was the p a t t e r n f o r the joints that produced the top values in the s e r i e s .

SEASONAL E F F E C T

Data and g r a p h s 10 t o 12 indicate t h a t the b e s t panels w e r e those a s s e m b l e d i n the M a r c h

-

August period. Leakage

r e s u l t s w e r e b e t t e r , however, f o r panels a s s e m b l e d between September and March. The change in p a t t e r n during the l a s t half of the p e r i o d could have r e s u l t e d f r o m t h e introduction of a new b r i c k and/or a change in m o r t a r flow values.

COMPARISON OF THE E F F E C T O F THE DIFFERENT MORTARS: MOISTURE CONTENT

Moisture contents of the m o r t a r s dropped f r o m 17.0 p e r cent f o r the 1:3:12 c e m e n t - l i m e - s a n d m i x t u r e t o 13.9 p e r cent f o r the 1:%:3 c e m e n t - l i m e combination. Moisture content values w e r e a l s o higher f o r high-flow m o r t a r s than f o r low-flow m o r t a r s ( s e e Table V).

WEIGHT O F MORTAR USED

P a n e l s r e q u i r e d slightly m o r e m o r t a r (by weight) a s the amount of cement in the m o r t a r was i n c r e a s e d , and panels with high-flow m o r t a r r e q u i r e d m o r e t h a n panels with low-flow m o r t a r . The f i g u r e s in Table V, however, indicated that d i f f e r e n c e s w e r e not g r e a t .

WEIGHT CHANGES DURING CURING PERIOD LEAKAGE TEST Most panels l o s t weight during the curing periods

a s they l o s t w a t e r by evaporation, and then gained weight a s they a b s o r b e d w a t e r during leakage t e s t s . In g e n e r a l ,

weight l o s s e s during the curing period w e r e s m a l l e r in m o r t a r s containing l a r g e r amounts of cement. In f a c t , low-flow m o r t a r panels containing 1:$:3 c e m e n t - l i m e - s a n d and c u r e d on e x p o s u r e , gained, r a t h e r than l o s t , s m a l l amounts of weight. E x p o s u r e - c u r e d panels w e r e not d r i e d before weight changes w e r e

d e t e r m i n e d ; t h u s , they r e f l e c t weather conditions during the curing p e r i o d and m o r e specifically, conditions just p r i o r t o t h e i r r e m o v a l f r o m the site. Lower weight l o s s e s f o r control panels of the predominantly cement (1:5:3 (C:L:S)) m o r t a r , however, w e r e conclusively indicated ( T a b l e VI).

S i m i l a r l y , the weight gains f r o m w a t e r absorption during leakage t e s t s w e r e lowest f o r the 1:$:3 c e m e n t - l i m e m o r t a r panels. Gains w e r e a l s o higher in control panels t h a n in e x p o s u r e c u r e d panels because the f o r m e r w e r e d r i e r and had a g r e a t e r capacity f o r wa.ter. Changing the flow of the m o r t a r in the panels did not influence weight gains signi- ficantly, high flow m o r t a r panels gaining only a few g r a m s m o r e than low flow m o r t a r panels. Differences in weight g a i n s due t o changes in the m o r t a r composition reflected changes in p o r o s i t y a s the m o r t a r s became d e n s e r with i n c r e a s i n g c e m e n t content.

CURING

Some handling of the panels o c c u r r e d during the curing period, p a r t i c u l a r l y panels c u r e d on the exposure s i t e located on the roof of the l a b o r a t o r y building. T h i s r e s u l t e d in s o m e b r e a k a g e , and other panels w e r e broken when they toppled f r o m t h e i r s u p p o r t s on the exposure s i t e during s t o r m s . P a n e l s containing 1:3:12 (C:L:S) m o r t a r proved t o be the weakest on the b a s i s of b r e a k s during the curing period. Seven w e r e broken before leakage t e s t s , and another four l o s t one b r i c k but w e r e t e s t e d a s f o u r - b r i c k panels. At the other end of the s c a l e , the 1:$:3 (C:L:S) panels w e r e v e r y b r i t t l e d e s p i t e t h e i r s u p e r i o r s t r e n g t h , and eight, including s i x control panels, w e r e broken before testing.

The m o s t durable panels w e r e t h o s e containing 1:1:6 (C:L:S) m o r t a r ; only one was

damaged

with the l o s s of one b r i c k , p e r m i t t i n g it t o be t e s t e d a s a f o u r - b r i c k panel. Next b e s t w e r e the panels of 1:2:9 (C:L:S) m o r t a r ; one was broken and another l o s t one brick. This information i s s u m m a r i z e d i n Table VII.

LEAKAGE

T h e r e was not sufficient leakage through the panels in the study t o justify a f a i r c o m p a r i s o n on the b a s i s of

leakage r e s u l t s . R e s u l t s s u m m a r i z e d i n Table VIII, however, indicated l e s s leakage a s the amount of cement in the m o r t a r was i n c r e a s e d . This evidence was supported by data in Tablc VI, which indicated the l e a s t w a t e r absorption t o be during leakage t e s t s in panels of 1:$:3 (C:L:S) m o r t a r . R e s u l t s a l s o indicated l e s s leakage in panels of 1:3:12,

1:2:9 and 1:l:b (C:L:S) m o r t a r having low flow values, and with high flow values f o r panels of 1:$:3 (C:L:S) m o r t a r . Water a b s o r p t i o n data during leakage t e s t s a l s o supports this p a t t e r n . Data a l s o indicated that exposure c u r e d panels leaked m o r e than control panels f o r a l l m o r t a r s except

the 1:1:b (C:L:S) combination in which t h e r e was no difference. T h i s m a y possibly be explained by the f a c t that i t was e a s i e r t o "push" w a t e r through the p a r t i a l l y s a t u r a t e d exposure

panels than through the d r i e r control panels. Water absorption d a t a provided evidence that control panels had a g r e a t e r

capacity f o r w a t e r than t h e e x p o s u r e panels.

The leakage p a t t e r n a l s o v a r i e d with the m o r t a r combinations. E a r l y leakage in panels cor~tainirlg 1: 3: 12 and 1:2:9 (C:L:S) m o r t a r s diminished a s thc t c s t period p r o g r e s s e d , and finally stopped. In panels of 1:I:h (C:Z,:S)

m o r t a r , t h e r e was a l s o a g r a d u a l reduction in leakage, but i t was not a s pronounced a s in panels of the l i m e m o r t a r s . T h e r e was no leakage i n panels of 1:$:3 c e m e n t - l i m e m o r t a r t o u s e a s a comparison.

Any conclusions drawn on the b a s i s of leakage r e s u l t s m u s t be considered with r e s e r v a t i o n in view of the limited o c c u r r e n c e of leakage.

BOND STRENGTH

Highest individual bond s t r e n g t h values o c c u r r e d in panels containing 1:+:3 c e m e n t - l i m e m o r t a r , but the highest a v e r a g e values p e r panel w e r e r e c o r d e d f o r those of 1:1:6 c e m e n t - l i m e m o r t a r . T h i s m a y not have p r e s e n t e d a t r u e picture since a v e r a g e values f o r the 1:$:3 c e m e n t - l i m e m o r t a r s e r i e s m a y have been lowered by poor values f o r joints

damaged by r e c o i l during the testing operation.

In the 1:3:12 (C:L:S) m o r t a r panels, the b e s t values o c c u r r e d in panels having m o r t a r at flow of 125 p e r cent and c u r e d on exposure. In the 1:2:9 (C:L:S) m o r t a r panels, b e s t values w e r e a s s o c i a t e d with 110 p e r cent flow m o r t a r and exposure curing. The 1:1:6 (C:L:S) m o r t a r panels had b e s t values a t 125 p e r cent flow c u r e d on exposure and a s i m i l a r p a t t e r n o c c u r r e d i n the 1:$:3 (C:L:S) m o r t a r panels. In a l l but one i n s t a n c e , values f o r exposure c u r e d panels w e r e b e t t e r than t h o s e f o r control panels. The one exception was f o r panels of 1:$:3 (C:L:S) m o r t a r a t 135 p e r cent flow a s s e m b l e d with a 60-second t i m e i n t e r v a l and a light tap. The g e n e r a l p a t t e r n s u g g e s t s that t h e a v e r a g e value f o r t h i s g r o u p should have been higher. R e s u l t s w e r e affected by s u b - n o r m a l values f o r s o m e joints probably damaged during testing. The o c c u r r e n c e of the highest individual values of the study i n t h i s p a r t i c u l a r group s u p p o r t s the suggestion that a higher a v e r a g e value should have been obtained.

A change in bond s t r e n g t h p a t t e r n was noted a s the

m o r t a r composition was a l t e r e d . F o r e a c h of the four m o r t a r s , the m o s t b r e a k s o c c u r r e d with the top b r i c k lifting f r o m the m o r t a r bed. With the 1:3:12 and 1:2:9 (C:L:S) m o r t a r s , t h i s type of b r e a k was a s s o c i a t e d with low bond s t r e n g t h

values. F o r t h e s e m o r t a r s and the 1 1 : 6 (C:L:S) combination, b e t t e r values r e s u l t e d f r o m b r e a k s in which s o m e of the m o r t a r r e m a i n e d sticking t o the top b r i c k , o r when the b r e a k o c c u r r e d d i r e c t l y through the m o r t a r bed. Improved bond s t r e n g t h vdlues, however, w e r e a s s o c i a t c d wilh lhc top b r i c k lifting f r o m the m o r t a r bed f o r the 1:1:6 (C:L:S) m i x t u r e , and, in

the 1:$:3 (C:L:S) m o r t a r panels, the highest values accompanied this type of break.

An indication of the effect of t h e different curing p r o c e d u r e s was noted by visual observation of f r a c t u r e d joints. With the 1:3:12 and 1:2:9 (C:L:S) m o r t a r s , t h e r e was a wider carbonation

band ringing the m o r t a r beds in control panels than in exposure c u r e d panels. The n a r r o w e r band around the beds in the

l a t t e r p a n e l s , however, appeared t o be m o r e thoroughly o r intensely carbonated. This m a y suggest a r e a s o n f o r higher bond s t r e n g t h values in the l a t t e r panels: a m o r e intense, although l e s s extensive, carbonation.

SEASONAL E F F E C T

P a n e l s containing e a c h different m o r t a r w e r e a s s e m b l e d a t monthly i n t e r v a l s during a 12-to 16-month period. Thus, the panels on the exposure site w e r e c u r e d under e v e r y weather condition o c c u r r i n g during t h e different s e a s o n s of the y e a r . A study of the data f o r the v a r i o u s m o r t a r s in G r a p h s 1 t o 12 indicated that differences in the weather did not affect the end r e s u l t t o any significant d e g r e e . F i g u r e s

1 t o 3 f o r 1:3:12 c e m e n t - l i m e m o r t a r indicated that panels a s s e m b l e d between F e b r u a r y and S e p t e m b e r p e r f o r m e d b e t t e r than those a s s e m b l e d during the October

-

F e b r u a r y period.

T h e r e was no definite t r e n d f o r 1:2:9 and 1:1:6 c e m e n t - l i m e m o r t a r panels. Again, the p a t t e r n f o r 1:4:3 c e m e n t - l i m e m o r t a r panels indicated that the b e s t panels w e r e t h o s e a s s e m b l e d between M a r c h and August. The t r e n d in the l a t t e r p a n e l s , however, was discounted by the fact that

s e v e r a l new v a r i a b l e s , different b r i c k s , and changed m o r t a r flows w e r e introduced between October and M a r c h and m a y have accounted f o r a change in the p a t t e r n of r e s u l t s .

Changes in w e a t h e r during the curing p e r i o d s had a much s m a l l e r effect on r e s u l t s of the study than the difference between controlled l a b o r a t o r y and exposure site curing o r the d i f f e r e n c e s due t o the change in m o r t a r composition. CONCLUSIONS

T h e r e w a s no difference in panel p e r f o r m a n c e due t o s e a s o n a l weather changes during curing p e r i o d s except in panels containing 1:3:12 c e m e n t - l i m e m o r t a r , w h e r e

panels a s s e m b l e d between F e b r u a r y and S e p t e m b e r w e r e b e t t e r than t h o s e a s s e m b l e d between October and F e b r u a r y on the b a s i s of bond s t r e n g t h r e s u l t s .

T h e r e w e r e g r e a t e r d i f f e r e n c e s , however, between panels c u r e d u n d e r controlled l a b o r a t o r y and exposure site

conditions. All panels p e r f o r m e d well during leakage t e s t s , but an a n a l y s i s of panels in which m i n o r leakage o c c u r r e d

suggested a higher incidence of leakage in exposure c u r e d panels. This m a y have r e s u l t e d f r o m the fact that exposure c u r e d panels did not d r y out a s well during curing. Thus, some of the w a t e r a b s o r b e d by the d r i e r control panels penetrated the somewhat d a m p e r exposure panels. The b e s t bond s t r e n g t h r e s u l t s o c c u r r e d in exposure c u r e d panels.

Among the m o r t a r combinations, the panels of 1:::3 and

1:1:6

c e m e n t - l i m e m o r t a r p e r f o r m e d b e s t on the b a s i s of both leakage and bond s t r e n g t h r e s u l t s . P a n e l s with the f o r m e r m o r t a r w e r e b e s t on the b a s i s of leakage r e s u l t s and they produced b e s t a v e r a g e bond s t r e n g t h r e s u l t s .

They w e r e not a s b r i t t l e a s the panels containing the s t r o n g e r 1:*:3 (C:L:S) m o r t a r .

Differences in flow r a t e s of the m o r t a r s a l s o produced d i f f e r e n c e s in r e s u l t s . P a n e l s with low flow (110 p e r cent) produced b e s t r e s u l t s f o r 1:3:12 and 1:2:9 (C:L:S) m o r t a r s w h e r e a s the 125 p e r cent flow value gave b e t t e r r e s u l t s f o r the 1:1:6 (C:L:S) m o r t a r panels. T h e r e was no r e a l

a

difference between 125 p e r cent and 135 p e r cent flow f o r panels containing I:$: 3 cement - l i m e m o r t a r .

I ri r i l l i

1

I ~ r i m r n r n m a ~ m a e m I I m I I (. I I a - 4 QL C .rl C . P i n) Q C ri 0

c"

U ii) Y;

a

H r i m U W r :

o

u' ii) .ri m e & 4 P i-i 4 0 V, %. 'P1 -u

f::

0 a d -0 s ri C a a 0 i t ' 4

2 :

T, ii) C

2

I

ii)

ILeaLaz~ a n d

Bond s t r e n ~ t h

R e s u l t s f o r P a n e l s contain in^.

1 : 2 : 9

C e m e n t - L i m e + l o r t a r I

r

I

1

/

_{W e i g h t} i

C h a n g e

;

'

_{D u r i n g C u r i n g}

₁

_{T o t a l}

W a t e r A b s o r b e d

Date of

( e m )

A s s e m b l v

1

2

i

L e a k a r e ( m l )

1

2

-

9 0

-190

-102

- 2 6 5

-

3 5 1 - 2 5 7

-129

'

- 2 9 5

/

-

3 2

-218

+

7

- 1 9 5

+

1 3

-202

- 2 3 5

D u r i n g L e a k a g e

Average

Bond

I

277

1

1 9 . 4

2 . 8

1

1 2 . 5

j

287

I

:

1 1 . 1

j

24 8

'

2 8 . 9

/

5 . 9

1

8 . 5

i

3 0 8

2 1 . 6

1 4 . 4

I 1

6 . 2

j

T e s t

( r x l )

1 0

1 5 3

1 2 5

0

1 7 0

0

0

o

1 6 0

( m l j

S t r e n n t h

i ~ s i )

I

2

0

1

0

i

$i202

3 2 5

;

0

0

i

278

i

3 4 5

I

:

1

2 5 . 9

1 O l O !i

2 6 3

,

2 7 5

1

1 4 . 3 j 2 2 .

j i !

0

1

0

!

210

i

3 0 0

; I

1 3 . 3 1 1 3 . 7

i

i

1 2 . 8

1 7 . 3

j

1 3 . 6

2 0 . 0

2 0 . 9

1 4 . 2

2 ₀

o

0

0 0 0

27 7

'

2 1 . 7

;

2 6 0

I

----

I

3 2 0

I

3 3 . 5

-10;

- 1 8 0

i llXP

4 4

1

E X P

4 j D

1

.Jan,'64

- 1 7 0

0

1 7 0

o

j

1 8 2

O

i

1 6 9

0

I

2 0 5

o

i

1 7 0

0

2 0 3

299

2 1 9

2 5 3

I . . 1 t.XP

4

j

/

E I P

4

jl) i

J a n 1 6 4

1 -

2 5

I

0

0

217

2 6 . 9

2 3 . 5

3 2 . 0

288

2 5 5

2 9 0

277

- 2 0 j

1

l : X P

4 6

_{1 E I P}

46D

_I

F e b / 6 4

_{I -}

₃₅

I

2 2 . 5

i

1 0 . 0

-16

2 0 0 I

2 0 5

i

2 j 3

i 3 0 . r

/

2 9 . 0

j I'XP

4;

'

E I P J ; D

i

F e b / 6 4

I

-

7 0

- l g j

210

3 3 0

2 2 . 6

j

5 . 3

i i _i 1 i

x

SI, :-

S l i g I i t

-

n o t m e a s u r a b l e

. . =

4 b r i c k p a n e l

-

t o t a l a d j u s t e d t o e q u a l

5

b r i c k p a n e l

'TABLE 111

L e a k a c e

a n d 1301ld

S t r e n g t h

1:eslllt.s for P a ~ l e l s contain in^ 1 : l : h C e m e n t - L i m e M o r . t a r . P a n e l 1 E I P

4 6

;L?

4 9

E i F

5 1

EX-2

E X ?

5 3

E X ?

54

EXP 5 5

EXP 5 a

EXP 57

EXP 5 6

E X P

59

EXP

6 0

E X P

6 1

EXP 6 2

E X P

6 3

EXP 6 4

E X P 6 5

E X P

6 6

E X P

6 7

E X P 6 5

EXP 6 9

E K P 7 0

EXP 7 1

ESP 7 2

SI.'

-

S l i g h t

--

n o t m e a s u r a b l e

.-

-

4 b r i c k p a n e l

--

t o t a l a d j u s t e d t o e q u a l 5 b r i c k p a n e l

D a t e

o f

A s s e d v

~ a r / 6 4

~ o r / 6 4

~ ~ r / 6 4

Apr/64

~a:.7/64

No.

2

FXP

48D

Z X P

4 9 0

E X P j l D

EXP j2D

EXP 5 3 0

E X 1

5 4 0

EXP

j j D

EXP j 6 D

EXP j7D

I

EXP j8D

E X ?

59D

EXP 60D

EXP 61D

EXP 62D

E X ?

63D

EX?

64D

E S P 6 5 0

EXP 66D

E X P

6 j D

F . S P 6 "

E X P

69D

EX? ?OD

EXP 7 1 D E X P ; Z D Weight Change

D u r i n g C u r i n g

G,,,

1

- 7 5

-

7 5

+

7

-

5 0

-

6 8

2

- 1 4 5

-180

-1

j 7

-194

-147

-155

-140

- 1 9 1

-130

----

-162

-190

- 1 6 5

-180

-144

-155

-130

-153

-1.18

-156

- 1 6 2

-147

- 1 5 3

- 1 4 9

T o t a l

L e a k a c e ( m l )

1 I

2

0

"

0

I

:

x a Y / 6 4

2 u n e / 6 4

I

' 2 5

- 7 2

~ u n e / 6 4

,

- 6 5

J u l y / , 6 4

1

i-

1 5

J u l j 7 / 0 4

~ u ~ / 6 4 + 1 1 0

I

----

A L L ~ / ~ ~

+

3 0

0

0

0

0 0

s e p t / 6 4

s e p t / 6 4

0 c t / 6 4

0 c t / 6 4

~ o r r , ' 6 4

~ o v . 6 4

Dec.'64

Dec:6J

i a n / o j

> a n : / 6 j

Water

A b s o r b e d

D u r i n g

L e a k a g e

0

0

0

SL& 0

-

7

-

7 3

-

8

+

2

-

5 5

-

6 8

P?

-

,

3

-117

-

9 5

-

l'

5

T e s t

(gm)

1

1 4 7

1 6 5

12.5

1 3 8

1 1 5

1 5 8

1 0 2

A v e r a g e Bond

S t r e n ~ t h

( p s i

j

F e b / b

j

3 0

F e b / 6 j

/

1 3 3

( m l )

2

2 6 8

3 1 3

2 2 5

24 3

2 3

2

2 2 0

2 0 2

1

3 8 - 7

4 1

.O

4 0 . 6

5 4 . 1

3 5 . 6

5 5 . 9

3 8 . 8

0

:

0

0

1

0

1 3 0

1

110

3 ~ 1 1 9

1 O j

1 2 7

1 2 0

1 3 8

1 1 8

1 3 0

1 5 5

1 4 0

1 5 4

204

1 9 0

1 6 0

1 7 2

1 6 0

2

2 1

. 0

2 1 . 6

2Q.2

j 1 . 3

1 7 . 5

2 9 . 7

3 2 . 1

0

0 0

0

0

0

0

0

0

SL$

0

0

0

0

0

0

0

0

0

1 5

0

0

2 3 2

1

3 . 4

I

l 5 * 5

1 9 9

2 0 7

2 1 6

2 2 2

2 0 4

2 1 0

1 9 5

2 0 0

2 6 0

226

2

57

24 5

2 3 2

1 7 5

2 2 1

2 5 1

1

,

0

1

0

0

2 5 . 5

5 6 . 3

4 7 . 3

3 3 . 5

3 3 . 3

24

.

0

6 5 . 4

5 4 . 6

3 7 . 5

6 0 . 4

4 8 . 0

5 9 . 7

6 0 .

j

5 8 . 7

54.5'

5 5 . 6

,

13

1 5 . 6

1 3 . 3

3 5 . 4

4 4 . 3

3 5 . 4

3.7.0

4 0 . 4

3 9 . 7

1 8 . 5

3 0 . 4

4 9 . 5

3 4 . 9

6 6 . 0

3 3 . 0

5 0 . 0

l j . 9

,

T A B L E I V L e a k a g e

a n d Bond S t r e n ~ t h

R e s u l t s f o r

P a n e l

P z n e l

1

EXP 7 3

EXP 7 4

EXP

$ 5

EXP 7 5

EXP 7 7

EXP 7 3

E X P

7 3

EXP

89

EXP 9 1

EXP 92

EXP 43

E X P

94

E X P

35

EXP

36

EXP 37

EXP 38

EXP ,39

EXP $90

EXP 91

EXF 9 2 EXP

93

E X P

94

E X P

9 5

E X P

96

EXP

9

:

EXP 98

SL' =

S l i g h t

--

n o t m e a s u r a b l e

2 , . = 4

b r i c k p a n e l

--

t o t a l

a d j u s t e d

t o

e q u a l 5

b r i c k

p a n e l

No.

2

EXP

73D

EXP

74D

EXP

75D

EXP 76D

E X P

77D

EXP 78D

EXP 79D

EXP 80D

E X P

8 1 ~

EXP 8 2 ~

EXP 83D

EXP 84D

EXP 85D

EXP 86D

E X P

87D

EXP 88D

EXP 89D

E X P

90D

EXP 91D

EXP 92D

EXP 93D

E X P

94D

E X P

95D

EXP 96D

E X P

97D

EXP 98D

I

Weight

Change

D a t e of

Assembly

Mar/65

~ a r / 6 5

Apr/65

~ ~ r / 6 5

~ a ~ / 6 5

May/65

J u n e / 6 5

J u n e / 6 5

J u l y / 6 5

~ u 1 ~ / 6 S

Aug/65

Aug/65

S e p t / 6 5

S e p t / 6 5

O c t / 6 5

0 c t / 6 5

~ o v / 6 5

~ o v / 6 5

~ e c / 6 5

~ e c / 6 5

J a n / 6 6

~ a n / 6 6

~ e b / 6 6

~ e b / 6 6

~ a r / 6 6

~ a r / 6 6

T o t a l

D u r i n g C u r i r g

Leakage

1 S L ~ S L S L ~ 0

0

0

---

0 0 0 0

0

0

---

0

0

0

0

0

0

0 0 0 0

0

0

1

t i 5

-23

+

7

-1

5

+20

1 6 2

---

-

6

+ I 5

6 2 3

t 6 5

+25

-17

---

-18

-25

-29

-38

-30

-35

-45

-69

-80

-85

-60

-38

( m l )

2

-

-

0 0 0 0

0

0

-

0

0

0

0

0

0

-

0

0 0

0

0

-

0

-

0

0 Water

A b s o r b e d

D u r i n g L e a k a g e

( g m

2

----

----

-110

-110

-103

-

99

-104

[

-108

----

-108

-105

-100

-117

-115

-

6 5

----

-100

-114

-138

-113

-115

----

- 1 1 2

----

-120

-132

T e s t 1

1 1 6

7 2

1 9 7

9

0

63

1 1 2

---

7 5

7 1

6

1

6

1

6 3

3 5

--a

5 0

5 0

5 0

47

4 0

5 0

64

7

2

7

3

6 0

5 3

6 0

A v e r a g e Bond

(am)

( m l )

2

---

---

1 3 2

1 2 3

1 0 0

9 0

7 8

1 5 0

---

11.5

1 0 1

1 2 5

8 3

8 9

1 1 0

---

1 0 0

90

1 0 4

1 1 5

1 3 0

---

1 1 4

---

1 2 6

1 3 5

S t r e n f i h

1

3 7 . 0

----

3 5 . 0

5 7 . 4

4 8 . 9

5 1 . 3

----

23.4

63.7

61.9

7 1 . 2

5 8 . 6

23.7

1 4 . 9

1 7 . 9

1 1 . 5

2 0 . 0

1 9 . 7

4 6 . 8

3 8 . 9

2 8 . 3

26.4

3 4 . 9

2 8 . 9

4 0 . 7

22.7

( p s i )

2

5 8 . 7

----

3 5 . 2

4 2 . 7

8 2 . 5

6 8 . 4

5 7 . 8

1 4 . 7

----

6 3 . 4

4 8 . 4

5 8 . 1

1 1 . 4

2 4 . 2

4 . 5

----

1 8 - 4

4 - 5

3 5 - 9

2 1 . 2

7 . 7

----

2 0 . 8

----

20.3

1 9 . 9

a = p a n e l s a s s e m b l e d w i t h 6 0 s e c . t i m e i n t e r v a l and l i g h t t a p b

-

p a n e l s a s s e m b l e d w i t h 30 s e c . t i m e i n t e r v a l and h e a v y t a p

-

Flow

( % I

1 1 0 1 2 5 1 3 5

1 4

5

Summary o f M o i s t u r e C o n t e n t s a n d W e i g h t s o f M o r t a r Used D u r i n g P a n e l Assemblv W e i g h t o f M o r t a r IJsed P e r P a n e l (gm) 1 l : z : n C : I , : S 1 4 . 0 1 3 . 9 1 4 . 4 1 5 . 0 Tvne of M o r t a r

I

1 : 1 : 6 C : L : S 1 : R : 1 2 C : L : S 1:Z:UC:L:S M o i s t u r e C o n t e n t ( % ) 1 5 . 2 1 6 . 2

1 6 . 8

1 7 . 4

1 6 . 6

l 7 . 5

Flow a n d C u r i n g C o n d i t i o n s 1 : ? : 1 2 C : L : S 1 : 2 1 1 0 % e x p o s u r e 1 1 0 % c o n t r o l 1 2 5 % e x p o s u r e 1 2 5 % c o n t r o l a a 1 3 5 % e x p o s u r e 1 3 5 % c o n t r o l b135% e x p o s u r e

b 1 3

5% c o n t r o l

1 4 5 % e x p o s u r e 1 4 5 % c o n t r o l

-

24 gm. -155 gm.

+

1 8 gm. -186

gm.

T v ~ e of M o r t a r 9 C : L : S

I

1 :1 : 6 C : L : S ~ : $ : . ~ c : L : s

I

+ I 6 7 gm. +231

gm.

+207

gm.

+262 gm. +186 gm. +283 gm. + I 8 8 gm. +284 g m .

-

1 gm. -190 gm.

-

4 6 gm. -213 gm.

-

2 1 gm. -148 g m .

-

5 5 gm -168

gm.

+ I 1 6 gm.

- - - -

- - - -

+

79 gm. + I 0 1 gm. + 7 5 g m . + I 1 5 gm.

+

56 gm. i l l 5 g m .

+

6 0 gm. + I 1 3 g m . +134 g m . +226 gm. + I 4 7 gm. +227 gm. A = W e i g h t l o s s d u r i n g c u r i n g p e r i o d

+

1 5 gm.

---

+

1 2 gm. -101 gm.

+

6 gm. -107 gm.

-

49 gm.

-117

gm.

-

53 gm. -120 g m . B = Water a b s o r b e d d u r i n g l e a k a g e t e s t T A B L E V I Summary of Weight C h a n g e s D u r i n g C u r i n g P e r i o d s a n d Water A b s o r b e d D u r i n g L e a k a g e T e s t s f o r V a r i o u s P a n e l s

PANEL DATA Type of M o r t a r I : , ? :12C:L:S 1 : Z : g C : L : S 1 : 1 : 6 C : L : S ~ : : : . ~ C : L : S . E x ~ o s u r e C o n t r o l E x ~ o s u r e C o n t r o l E x o o s u r e C o n t r o l E x u o s u r e C o n t r o l P a n e l s A s s e m b l e d 2 2 2 2 2

4

24 24 24 2 6 2 6 P a n e l s Broken

5

2 1 0 0 0 2

6

P a n e l s T e s t e d ( ~ e a k a ~ e )

1 7

2 0 23 2

4

24 24 2 4 20 P a n e l s T e s t e d (Bond S t r e n g t h )

1 7

1 9

23 2 4 24 24 2 4 2 0 3 0 . of M o r t a r J o i n t s

6 8

7 6

₉

_{1 9 6 9}

₅

₉

₆

₉

₆

₈

₀ ?lo. of Bond S t r . V a l u e s

5 5

5

6

8

7

93

9

3

94 79 6

5

TABLE V L I Summary o f P a n e l B r e a k a g e