W. G. ROOKE & ASSOCIATES LTD.

haltingnosyUrban and Civil

Nov 29, 2013 (3 years and 8 months ago)

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W. G. ROOKE & ASSOCIATES LTD.

Consulting Engineers


169 Kingston Row, Winnipeg, Manitoba R2M 0T1

Phone/fax 204 237
-
5075 E
-
mail: wrooke@shaw.com





FINAL REPORT


PHASE 3


TESTING OF CONCRETE BRICK MIXES


AND


TRIAL MIXES OF

MAG
-
MENT CEMENT






Prepared for:

LBJV Incorporated

Brandon, Manitoba



Prepared by:

Wally Rooke, P. Eng.





January 2004






Table of Contents












Page


1.0

Introduction:.......................................................
..............…..



2


2.0

Test Procedures .............................................................…..




2


3.0

Mix Designs



3.1

Mixes utilizing Portland cement or lime


as the lagoon ash activator and binder ........




4



3.2

Mixes usin
g Mag
-
ment binder .......................……….



4


4.0

Test Results



4.1

Strength, Cementitious mixes ..................................




6



4.2

Strength, Mag
-
ment mixes .......................................




7



4.3

Length change Results .......
.....................................




11


5.0

Discussion of Results




5.1

Cementitious mixes ...............................................…



12



5.2

Mag
-
ment Mixes ....................................................…



13



5.3

Ongoing testing ...
.....................................................




17


6.0

Conclusions

.......................................................................



17



Appendix A: Mix Designs


A.1:

Mixes utilizing Portland cement or lime

as the lagoon ash activato
r and binder ……



20


A.2:

Mixes using Mag
-
ment binder ............................……



21



A:3

ASTM
Designations……………………………………
25


A.4
Freeze Thaw results………………………………. 26




LBJV TEST MIXES

January 2004


2

W.G. Rooke & Associates Ltd.



1.0

INTRODUCTION



W.G. Rooke & Associates Ltd. (WGRA) was retained by LBJV Incorporated in July
2003 to proceed with a program to create and test numerous mix designs primarily
utilizing waste lagoon ash and/or water treatment plant sludge. A portion of the
program was a
n extension of tests performed by WGRA in 2002 and early 2003 to
create cementitious mixes utilizing lagoon ash from Manitoba Hydro’s Brandon G.S.
that would satisfy criteria for non
-
load bearing compressed bricks . The second
portion of the current progr
am sought to utilize these waste products and/or
commercial sands and aggregates in innovative mixes using a two
-
component
magnesium phosphate cement known commercially as Mag
-
ment.


The tests constitute the third phase of an ongoing program. Variations
of the two
most promising mix designs determined in Phase 2 of the program were selected for
further refinement and test. Many of the cementitious mixes included a fine sand in
order to reduce the potential for drying shrinkage. The intent was to develo
p mix
designs with Portland cement, lime or Mag
-
ment which would satisfy both the
minimum strength requirement (4.14 MPA) and drying shrinkage criteria required by
ASTM C129 for Non Load Bearing Concrete Bricks. In total some 29 mix designs
were tested fo
r compressive strength over various time periods. Selected mixes were
further tested for length change due to drying shrinkage.


The program was subdivided into two mix categories as either Cementitious [mixes
including Portland cement or lime] or Mag
-
m
ent. The mix codes for all Mag
-
ment
mixes include the prefix “MM”. Mix Codes for the cementitious mixes were alpha
-
numeric consistent with codes used in earlier stages of the program.


2.0

TEST PROCEDURES


The various mix designs (documented in Appendix
A) were hand batched in small
quantities in the test laboratory of ENG
-
TECH Consulting Limited, Winnipeg, under
direct supervision of WGRA. Batches for six Cementitious and 23 Mag
-
ment mix
designs were prepared.


For the cementitious mixes, the intent was

to provide mix proportions with a water
content somewhat higher than actually required to activate the cementitious reaction
in each mix; excess water content in these mixes, however, was reduced during
compression by extrusion of the excess water through

pressure release holes near
the bottom of the mould. In order to simulate a compactive effort representative of the
AECT 5000 Compressed Earth Block machine of interest to LBJV, a pressure of 1700
psi was applied during casting to each moist cementitious

mixture within the mould.



Test specimens of the Cementitious (Portland cement or lime) mixes were moulded
within a rigid steel mould measuring 6 X 6 inches square and approximately 3 inches
high after compaction in the mould in order to simu
late production procedures for
LBJV TEST MIXES

January 2004


3

W.G. Rooke & Associates Ltd.

moulded bricks
.
Cutting of these bricks later permitted fabrication of either 3
-
inch test
cubes for compression testing or longer prisms for length change testing. The basic
chemical interaction within these specimens was b
etween the cement or lime and the
lagoon ash which is included in all these mixes.


Since significant compaction of the bricks is not contemplated for Mag
-
ment mixes
during commercial production, the Mag
-
ment test samples were only hand
-
compacted
into the

moulds. Nor is the inclusion of lagoon ash necessary for the chemical
reaction of the cementing component of Mag
-
ment mixes so it was not always
included in the mixes tested.


Ferric sulphate sludge from the Brandon city water treatment plant was inclu
ded in
several Mag
-
ment mixes; because of known negative interaction in Cementitious
mixes and low test results in earlier phases of this program, it was not included in any
Cementitious mix.


Test specimens for the Mag
-
ment mixes were generally cast direc
tly into 2
-
inch cube
moulds commonly used for testing of mortars. Where larger aggregate was used as a
filler or supplementary tests were contemplated, larger cylindrical specimens were
cast.



For all tests, the lagoon ash was oven dried and sieved throu
gh a 2.5 mm sieve. This
assured optimum dispersal of the ash into each small batch. It should be noted
however that the moisture content of the lagoon ash in stockpile at Brandon
approaches 30%. This will be a batching consideration for any full scale ba
tching
using this material. In some mix designs in the Mag
-
ment portion of this program, a
30% moisture content was simulated in order to assess the effect of this water on
strength development.


All cementitious specimens were wrapped in plastic bags to
prevent evaporation and
subjected to room temperatures of approximately 23
o
C until cut into cubes and tested
for compressive strength at 28 days. Additional samples were cut into slender 3 X 3 X
6 inch prisms in preparation for determination of length chan
ge due to drying
shrinkage. These specimens were not permitted to air dry prior to length
-
change
testing.


Mag
-
ment test specimens did not require moist curing and were air cured at room
temperature to permit the expected off
-
gassing of ammonia as the chem
ical reaction
proceeded.


LBJV TEST MIXES

January 2004


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W.G. Rooke & Associates Ltd.

3.0

MIX DESIGNS


3.1:

MIXES USING PORTLAND CEMENT OR LIME AS THE
LAGOON ASH ACTIVATOR AND BINDER



Six Cementitious mix designs were selected from previous phases of this test
program which had demonstrated a likelihood of sat
isfying the ASTM C129 tests
criteria for strength and length change. A set of three mixes utilized Portland cement
as the activator for the pozzolanic interaction with the lagoon ash; three mixes utilized
hydrated lime for the same purpose. None of these

mixes included sludge since
previous tests had demonstrated that sludge ha a negative influence on strength
development in cementitious mixes.


Each set included one with lagoon ash alone as the “filler” material. To reduce drying
shrinkage potential in
the mixes, sand in varying proportions was included in the
remaining cement or lime
-
based mix designs. Details of all six mix designs are
provided in Appendix A1.



3.2

MIXES USING MAG
-
MENT BINDER


Tests of the Mag
-
ment proceeded in several stages over s
everal months as additional
information and experience was gained in handling this material. Because of the
rapid rate of strength gain anticipated (and experienced) for this binder, repetition of
several promising mix designs with appropriate modificatio
n was possible within days
of the initial casting of test specimens. Some variations in batching sequences also
were conducted.


All filler material was sieved through 5 mm sieves. MMw (wet component of Mag
-
ment) was cooled to the 5
o
C range. MMd (dry co
mponent of Mag
-
ment) and other
materials at room temperature. The mixing procedure was always to batch together
the two Mag
-
ment components first and then to add “fillers” as noted. The percentage
of each component (by mass) is indicated for each mix desi
gn.


3.2.1

MOISTURE SENSITIVITY TESTS



Initially, a series of five lagoon ash mixes were batched at low (10% and 20%) Mag
-
ment contents and various moisture contents from 0% to 40%. The intent was to
determine the sensitivity of all Mag
-
ment mixes to
water content in the ash. However,
the 7
-
day compressive strength results for these cubes were exceedingly low. The
fragility of these specimens and their negligible strength indicated that initial
assumptions and methodology required re
-
evaluation. It
was presumed that there
was both an insufficient quantity of Mag
-
ment binder in the mixes and that insufficient
blending of the two components (dry and wet) of the Mag
-
ment had occurred during
batching resulting in minimal chemical interaction. As a resu
lt, no conclusion as to
moisture sensitivity was possible.


Batching sequences and dosages were adjusted in all future batches.

LBJV TEST MIXES

January 2004


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W.G. Rooke & Associates Ltd.

3.2.2

MM BATCHES


For the initial part of the test program, mix proportions (listed in Appendix A2 with mix
codes from MM1 to M
M9) were batched and nine 2
-
inch cube specimens moulded for
testing at 4 hours and 1, 2, 7 and 28 days. The dry and wet components of Mag
-
ment
were batched together at a 2:1 ratio in the mixing bowl and the dry or damp filler (ash,
sludge or sand) added u
ntil a stiff mix was achieved. Despite cooling of the Mag
-
ment’s wet component to approximately 5
o
C, frequently the rapid reaction prompted a
rapid set and early stiffening of the batch, forestalling a assessment of the true
quantity of filler that could
have been absorbed. In subsequent tests, the dry/wet
Mag
-
ment ratio was altered to 1:1, greatly increasing the pot
-
life of each batch while
simultaneously permitting a much higher proportion of filler material into the batch.


Based on observations and r
esults of the above tests, at a later date fourteen
additional mix designs were batched and tested. These are listed as Supplemental
Mixes in Appendix A2.


The latter two mixes (MM12 and MM13) were batched late in the test program in
response to informati
on provided to WGRA by LBJV showing tests done at the
Argonne National Laboratory suggesting that the optimum “% powder” for the ash
was in the 50% and 60% range. These mixes reflect those findings. In addition, the
batch sequence for these two mixes onl
y was altered such that all dry “powder” [ash
and MMd] was blended first prior to addition of any liquid. Water was necessary to be
added to the MMw to improve workability.


All Mag
-
ment mixes include the prefix MM.




LBJV TEST MIXES

January 2004


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W.G. Rooke & Associates Ltd.


4.0

TEST RESULTS


4.1

CEMENTITIOUS MI
XES:

Compressive Strengths

Water content in cementitious mixes unknown because surplus squeezed out during compressive
moulding.











Mix

#

Components

Ratios



Age

Strength


Average


Remarks

Code







MPa


MPa



Mix 2A

A

Ash/
cement

94%/6%


28 d


4.98




B

Ash/cement

94%/6%


28 d


5.01




C

Ash/cement

94%/6%


28 d


4.72


Best cement


D

Ash/cement

94%/6%


28 d


4.38

4.8

mix











Mix 2S

A

VMA/ash/cement

74%/22%/4%


28 d


0


Fragile;


B

VMA/
ash/cement

74%/22%/4%


28 d


0.392


Not


C

VMA/ash/cement

74%/22%/4%


28 d


0.513


enough


D

VMA/ash/cement

74%/22%/4%


28 d


0.484

0.34

cement










Mix 2S2

A

VMA/ash/cement

72%/22%/6%


7 d


3.7





B

VMA/ash/cement

72%/22
%/6%


7 d


3.4


3.5



C

VMA/ash/cement

72%/22%/6%


14 d


4.7





D

VMA/ash/cement

72%/22%/6%


14 d


3.9


4.4












Mix 5A

A

Ash/lime 4:1

80%/20%


28 d


5.29


Best


B

Ash/lime 4:1

80%/20%


28 d


6.86


lime


C

Ash/lime 4:1

80%/20%


28 d


6.74


mix


D

Ash/lime 4:1

80%/20%


28 d


6.61

6.4











Mix 5S1

A

VMA/ash/lime 4:1

44%/44%/11%


28 d


4.71




B

VMA/ash/lime 4:1

44%/44%/11%


28 d


5.57




C

VMA/ash/lime 4:1

44
%/44%/11%


28 d


4.86




D

VMA/ash/lime 4:1

44%/44%/11%


28 d


3.91

4.7











Mix 5S2

A

VMA/ash/lime 4:1

29%/57%/14%


28 d


4.93




B

VMA/ash/lime 4:1

29%/57%/14%


28 d


6.03




C

VMA/ash/lime 4:1

29%/57%/14%


28 d


4
.54




D

VMA/ash/lime 4:1

29%/57%/14%


28 d


5.57

5.3



LBJV TEST MIXES

January 2004


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W.G. Rooke & Associates Ltd.


4.2: MAG
-
MENT MIXES:

Compressive Strength


Except for MM12 & MM13, Mag
-
ment mixes batched as slurry


and "filler" added in % noted.



Ash and sludge sieved over 5 mm sieve.

Sand si
eved over 2.5 mm.














Mix

#

Components

Ratios


Test

Strength


Average


Remarks

Code






Age


MPa


MPa











MM1

A

MM2:1/ash/sludge

82%/11%/7%


4 h


13.8



Temp: 8 C

MM1

B

MM2:1/ash/sludge

82%/11%/7%


4 h


15.3

14.5

Stiff dough

MM1

C

MM2:1/ash/sludge

82%/11%/7%


24 h


27



MM1

D

MM2:1/ash/sludge

82%/11%/7%


24 h


24

25.5


MM1

E

MM2:1/ash/sludge

82%/11%/7%


3 d


37.2



MM1

F

MM2:1/ash/sludge

82%/11%/7%


3 d


36.7

37


MM1

G

MM2:1/ash/sludge

82%/11%/7%


11 d


50.6



MM1

H

MM2:1/ash/sludge

82%/11%/7%


11 d


57.3

54


MM1

I

MM2:1/ash/sludge

82%/11%/7%


29 d


60.7

60.7














MM2

A

MM2:1/Sludge

74%/26%


4 h


9.9


Temp:
4 C

MM2

B

MM2:1/Sludge

74%/26%


4 h


12.3

11.1



MM2

C

MM2:1/Sludge

74%/26%


24 h


13.3




MM2

D

MM2:1/Sludge

74%/26%


24 h


13.9

13.6



MM2

E

MM2:1/Sludge

74%/26%


3 d


16.4



MM2

F

MM2:1/Sludge

74%/26%


3 d


19.
6

18


MM2

G

MM2:1/Sludge

74%/26%


11 d


31.8




MM2

H

MM2:1/Sludge

74%/26%


11 d


32.6

32.2


MM2

I

MM2:1/Sludge

74%/26%


29 d


36.2

36.2











MM3

A

MM2:1/ash

75%/25%


4.75 h


11




Very stiff;

MM3

B

MM2:
1/ash

75%/25%


4.75 h


10.6

10.8

Rapid set

MM3

C

MM2:1/ash

75%/25%


24 h


18.9


Temp: 8 C

MM3

D

MM2:1/ash

75%/25%


24 h


18.1

18.5

Top

MM3

E

MM2:1/ash

75%/25%


3 d


30.8


surface

MM3

F

MM2:1/ash

75%/25%


3 d


31
.9

31.4

fissured

MM3

G

MM2:1/ash

75%/25%


11 d


42.9



MM3

H

MM2:1/ash

75%/25%


11 d


45.5

44.2


MM3

I

MM2:1/ash

75%/25%


29 d


44.3

44.3











MM4

B

MM2:1/ash/water

70%/23%/7%


4 h


7.3


7.3

Very fluid

MM4

C

MM2:1/ash/water

70%/23%/7%


24 h


14.3


Pourable

MM4

D

MM2:1/ash/water

70%/23%/7%


24 h


15.2

14.8


MM4

E

MM2:1/ash/water

70%/23%/7%


3 d


23


30% mc

MM4

F

MM2:1/ash/water

70%/23%/7%


3 d


24.9

24


MM4

G

MM2:1/ash/w
ater

70%/23%/7%


11 d


34.3



MM4

H

MM2:1/ash/water

70%/23%/7%


11 d


34.9

34.6


MM4

I

MM2:1/ash/water

70%/23%/7%


29 d


33.4

33.4





























LBJV TEST MIXES

January 2004


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W.G. Rooke & Associates Ltd.

Mix

#

Components

Ratios


Test


Strength


Average


Remarks

Code






Age


MPa


MPa


MM5

C

MM2:1/dry sand

68%/32%


24 h


23.2


Could

MM5

D

MM2:1/dry sand

68%/32%


24 h


19.3

21.3

absorb

MM5

E

MM2:1/dry sand

68%/32%


3 d


30.1


more

MM5

F

MM2:1/dry sand

68%/32%


3 d


33.1

31.6


sand

MM5

G

MM2:1/dry sand

68%/32%


11 d


56.2



MM5

H

MM2:1/dry sand

68%/32%


11 d


56.4

56.3


MM5

I

MM2:1/dry sand

68%/32%


29 d


68.8

68.8











MM6

A

MM2:1/damp sand

63%/37%


4 h


7.9


Fluid mix

MM6

B

MM2:1/damp
sand

63%/37%


4 h


10.8

9.4


MM6

C

MM2:1/damp sand

63%/37%


24 h


18.5


5% mc

MM6

D

MM2:1/damp sand

63%/37%


24 h


19

18.8


MM6

E

MM2:1/damp sand

63%/37%


3 d


29.8



MM6

F

MM2:1/damp sand

63%/37%


3 d


29.7

28.8


MM6

G

MM2:1/damp sand

63%/37%


11 d


52.6



MM6

H

MM2:1/damp sand

63%/37%


11 d


52.4

52.3


MM6

I

MM2:1/damp sand

63%/37%


29 d


58.8

58.8











MM7

A

MM2:1ash/sand

69%/6%/25%


4 h


9


Dry ash

MM7

B

MM2:1ash/sand

6
9%/6%/25%


4 h


10

9.5

+ sand

MM7

C

MM2:1ash/sand

69%/6%/25%


24 h


22



MM7

D

MM2:1ash/sand

69%/6%/25%


24 h


20.9

21.5


MM7

E

MM2:1ash/sand

69%/6%/25%


3 d


30.9



MM7

F

MM2:1ash/sand

69%/6%/25%


3 d


19.8

25.4


MM7

G

MM2:1ash/sand

69%/6%/25%


11 d


43.8



MM7

H

MM2:1ash/sand

69%/6%/25%


11 d


53.5

48.7


MM7

I

MM2:1ash/sand

69%/6%/25%


29 d


58.0

58.0











MM8

A

MM2:1/ash/sand

67%/6%/24%/3%


4 h


12.3


Wet

MM8

B

MM2:1/ash/sand

6
7%/6%/24%/3%


4 h


14.1

13.2

ash +

MM8

C

MM2:1/ash/sand

67%/6%/24%/3%


24 h


15.3


sand

MM8

D

MM2:1/ash/sand

67%/6%/24%/3%


24 h


18.6

17


MM8

E

MM2:1/ash/sand

67%/6%/24%/3%


3 d


24.9



MM8

F

MM2:1/ash/sand

67%/6%/24%/3%


3 d


26.5

25.7


MM8

G

MM2:1/ash/sand

67%/6%/24%/3%


11 d


41.4



MM8

H

MM2:1/ash/sand

67%/6%/24%/3%


11 d


44.3

42.9


MM8

I

MM2:1/ash/sand

67%/6%/24%/3%


29 d


44.6

44.6











MM9

A

MM2:1 neat

100%


4 h


12.3





Concave

MM9

B

MM2:1 neat

100%


4 h


10.5

11.4

shrinkage

MM9

C

MM2:1 neat

100%


24 h


18.5


in

MM9

D

MM2:1 neat

100%


24 h


20.3

19.4

first

MM9

E

MM2:1 neat

100%


3 d


28.9


cubes

MM9

F

MM2:1 neat

100%


3 d


25.3

27.
1

cast

MM9

G

MM2:1 neat

100%


11 d


47.4



MM9

H

MM2:1 neat

100%


11 d


47

47.2


MM9

I

MM2:1 neat

100%


29 d


40.4

40.4


LBJV TEST MIXES

January 2004


9

W.G. Rooke & Associates Ltd.

4.2: MAG
-
MENT MIXES:

Compressive Strength


Except for MM12 & MM13, Mag
-
ment mixes batched as slurry


and "filler" added in % noted.



Ash and sludge sieved over 5 mm sieve.

Sand si
eved over 2.5 mm.














Mix

#

Components

Ratios


Test

Strength


Average


Remarks

Code






Age


MPa


MPa











MM1

A

MM2:1/ash/sludge

82%/11%/7%


4 h


13.8



Temp: 8 C

MM1

B

MM2:1/ash/sludge

82%/11%/7%


4 h


15.3

14.5

Stiff dough

MM1

C

MM2:1/ash/sludge

82%/11%/7%


24 h


27



MM1

D

MM2:1/ash/sludge

82%/11%/7%


24 h


24

25.5


MM1

E

MM2:1/ash/sludge

82%/11%/7%


3 d


37.2



MM1

F

MM2:1/ash/sludge

82%/11%/7%


3 d


36.7

37


MM1

G

MM2:1/ash/sludge

82%/11%/7%


11 d


50.6



MM1

H

MM2:1/ash/sludge

82%/11%/7%


11 d


57.3

54


MM1

I

MM2:1/ash/sludge

82%/11%/7%


29 d


60.7

60.7














MM2

A

MM2:1/Sludge

74%/26%


4 h


9.9


Temp:
4 C

MM2

B

MM2:1/Sludge

74%/26%


4 h


12.3

11.1



MM2

C

MM2:1/Sludge

74%/26%


24 h


13.3




MM2

D

MM2:1/Sludge

74%/26%


24 h


13.9

13.6



MM2

E

MM2:1/Sludge

74%/26%


3 d


16.4



MM2

F

MM2:1/Sludge

74%/26%


3 d


19.
6

18


MM2

G

MM2:1/Sludge

74%/26%


11 d


31.8




MM2

H

MM2:1/Sludge

74%/26%


11 d


32.6

32.2


MM2

I

MM2:1/Sludge

74%/26%


29 d


36.2

36.2











MM3

A

MM2:1/ash

75%/25%


4.75 h


11




Very stiff;

MM3

B

MM2:
1/ash

75%/25%


4.75 h


10.6

10.8

Rapid set

MM3

C

MM2:1/ash

75%/25%


24 h


18.9


Temp: 8 C

MM3

D

MM2:1/ash

75%/25%


24 h


18.1

18.5

Top

MM3

E

MM2:1/ash

75%/25%


3 d


30.8


surface

MM3

F

MM2:1/ash

75%/25%


3 d


31
.9

31.4

fissured

MM3

G

MM2:1/ash

75%/25%


11 d


42.9



MM3

H

MM2:1/ash

75%/25%


11 d


45.5

44.2


MM3

I

MM2:1/ash

75%/25%


29 d


44.3

44.3











MM4

B

MM2:1/ash/water

70%/23%/7%


4 h


7.3


7.3

Very fluid

MM4

C

MM2:1/ash/water

70%/23%/7%


24 h


14.3


Pourable

MM4

D

MM2:1/ash/water

70%/23%/7%


24 h


15.2

14.8


MM4

E

MM2:1/ash/water

70%/23%/7%


3 d


23


30% mc

MM4

F

MM2:1/ash/water

70%/23%/7%


3 d


24.9

24


MM4

G

MM2:1/ash/w
ater

70%/23%/7%


11 d


34.3



MM4

H

MM2:1/ash/water

70%/23%/7%


11 d


34.9

34.6


MM4

I

MM2:1/ash/water

70%/23%/7%


29 d


33.4

33.4





























Mix

#

Components

Ratios


Test



Average


Remarks

LBJV TEST MIXES

January 2004


10

W.G. Rooke & Associates Ltd.

Strength

Code






Age


MPa


MPa


MM5

C

MM2:1/dry sand

68%/32%


24 h


23.2


Could

MM5

D

MM2:1/dry sand

68%/32%


24 h


19.3

21.3

absorb

MM5

E

MM2:1/dry sand

68%/32%


3 d


30.1


more

MM5

F

MM2:1/dry sand

68%/32%


3 d


33.1

31.6


sand

MM5

G

MM2:1/dry sand

68%/32%


11 d


56.2



MM5

H

MM2:1/dry sand

68%/32%


11 d


56.4

56.3


MM5

I

MM2:1/dry sand

68%/32%


29 d


68.8

68.8











MM6

A

MM2:1/damp sand

63%/37%


4 h


7.9


Fluid mix

MM6

B

MM2:1/damp
sand

63%/37%


4 h


10.8

9.4


MM6

C

MM2:1/damp sand

63%/37%


24 h


18.5


5% mc

MM6

D

MM2:1/damp sand

63%/37%


24 h


19

18.8


MM6

E

MM2:1/damp sand

63%/37%


3 d


29.8



MM6

F

MM2:1/damp sand

63%/37%


3 d


29.7

28.8


MM6

G

MM2:1/damp sand

63%/37%


11 d


52.6



MM6

H

MM2:1/damp sand

63%/37%


11 d


52.4

52.3


MM6

I

MM2:1/damp sand

63%/37%


29 d


58.8

58.8











MM7

A

MM2:1ash/sand

69%/6%/25%


4 h


9


Dry ash

MM7

B

MM2:1ash/sand

6
9%/6%/25%


4 h


10

9.5

+ sand

MM7

C

MM2:1ash/sand

69%/6%/25%


24 h


22



MM7

D

MM2:1ash/sand

69%/6%/25%


24 h


20.9

21.5


MM7

E

MM2:1ash/sand

69%/6%/25%


3 d


30.9



MM7

F

MM2:1ash/sand

69%/6%/25%


3 d


19.8

25.4


MM7

G

MM2:1ash/sand

69%/6%/25%


11 d


43.8



MM7

H

MM2:1ash/sand

69%/6%/25%


11 d


53.5

48.7


MM7

I

MM2:1ash/sand

69%/6%/25%


29 d


58.0

58.0











MM8

A

MM2:1/ash/sand

67%/6%/24%/3%


4 h


12.3


Wet

MM8

B

MM2:1/ash/sand

6
7%/6%/24%/3%


4 h


14.1

13.2

ash +

MM8

C

MM2:1/ash/sand

67%/6%/24%/3%


24 h


15.3


sand

MM8

D

MM2:1/ash/sand

67%/6%/24%/3%


24 h


18.6

17


MM8

E

MM2:1/ash/sand

67%/6%/24%/3%


3 d


24.9



MM8

F

MM2:1/ash/sand

67%/6%/24%/3%


3 d


26.5

25.7


MM8

G

MM2:1/ash/sand

67%/6%/24%/3%


11 d


41.4



MM8

H

MM2:1/ash/sand

67%/6%/24%/3%


11 d


44.3

42.9


MM8

I

MM2:1/ash/sand

67%/6%/24%/3%


29 d


44.6

44.6











MM9

A

MM2:1 neat

100%


4 h


12.3





Concave

MM9

B

MM2:1 neat

100%


4 h


10.5

11.4

shrinkage

MM9

C

MM2:1 neat

100%


24 h


18.5


in

MM9

D

MM2:1 neat

100%


24 h


20.3

19.4

first

MM9

E

MM2:1 neat

100%


3 d


28.9


cubes

MM9

F

MM2:1 neat

100%


3 d


25.3

27.
1

cast

MM9

G

MM2:1 neat

100%


11 d


47.4



MM9

H

MM2:1 neat

100%


11 d


47

47.2


MM9

I

MM2:1 neat

100%


29 d


40.4

40.4


LBJV TEST MIXES

January 2004


11

W.G. Rooke & Associates Ltd.












Mix

#

Components

Ratios


Test

Strength


Average


Remarks

Code






Age


MPa


MPa


MM1b

A

MM2:1/ash/sludge

62%/14%/10%/4%


1 d


8.7




B

MM2:1/ash/sludge

62%/14%/10%/4%


1 d


9.2

8.9



C

MM2:1/ash/sludge

62%/14%/10%/4%


7 d


20.2




D

MM2:1/ash/sludge

62%/14%/10%/4%


7 d


19

19.6



E

MM2:1/ash/sludge

62%/14%/10%/4%


31 d

22.6




F

MM2:1/ash/sludge

62%/14%/10%/4%


31 d

25.2

23.9











MM1c

A

MM4:3/ash/sludge

74%/13%/9%/4%


1 d


5.5




B

MM4:3/ash/sludge

74%/13%/9%/4%


1 d


6.2

5.8



C

MM4:3/ash/sludge

74%/13%/
9%/4%


7 d


15




D

MM4:3/ash/sludge

74%/13%/9%/4%


7 d


15.1

15



E

MM4:3/ash/sludge

74%/13%/9%/4%


31 d

17.6




F

MM4:3/ash/sludge

74%/13%/9%/4%


31 d

21.9

19.7











MM1d

A

MM1:1/ash/sludge

58%/31%/10%


1 d



9.8


Did not


B

MM1:1/ash/sludge

58%/31%/10%


1 d*


4

7.4

mould


C

MM1:1/ash/sludge

58%/31%/10%


7 d


19.1


well


D

MM1:1/ash/sludge

58%/31%/10%


7 d


18.1

18.6



E

MM1:1/ash/sludge

58%/31%/10%


31 d

24.2




F

M
M1:1/ash/sludge

58%/31%/10%


31 d

25.1

24.6











MM4b

A

MM2:1/ash/water

61%/30%/9%


1 d


4.6




B

MM2:1/ash/water

61%/30%/9%


1 d


4.6

4.6



C

MM2:1/ash/water

61%/30%/9%


7 d


11.2




D

MM2:1/ash/water

61%/30%/9
%


7 d


11.2

11.2



E

MM2:1/ash/water

61%/30%/9%


31 d

10.7




F

MM2:1/ash/water

61%/30%/9%


31 d

12.1

11.4











MM4c

A

MM1:1/ash/water

28%/55%/17%


1 d


0




B

MM1:1/ash/water

28%/55%/17%


1 d


2.9

1.5




C

MM1:1/ash/water

28%/55%/17%


7 d


3.3




D

MM1:1/ash/water

28%/55%/17%


7 d


3.2

3.2



E

MM1:1/ash/water

28%/55%/17%



31 d

2.7




F

MM1:1/ash/water

28%/55%/17%


31 d

3.2

3.0











MM6b

A

MM2:1/sand/w
ater

57%/41%/2%



1d


10.4




B

MM2:1/sand/water

57%/41%/2%


1 d


10.5

10.4



C

MM2:1/sand/water

57%/41%/2%



7 d


19.9




D

MM2:1/sand/water

57%/41%/2%


7 d


20.6

20.3



E

MM2:1/sand/water

57%/41%/2%


30 d

23.2




F

MM2:1/sand/water

57%/41%/2%



20.1

21.7











MM6bb

A

MM2:1/sand/water

51%/46%/2%


1 d


11.4




B

MM2:1/sand/water

51%/46%/2%


1 d


11.1

11.2



C

MM2:1/sand/water

51%/46%/2%


7 d


21.6




D

MM2:1/sand/water

51%/46%/2%


7
d


21.6

21.6



E

MM2:1/sand/water

51%/46%/2%



30 d

29.6




F

MM2:1/sand/water

51%/46%/2%


30 d

28.3

29.0



LBJV TEST MIXES

January 2004


12

W.G. Rooke & Associates Ltd.











Mix

#


Ratios


Test

Strength


Average


Remarks

Code






Age


MPa


MPa


MM6c

A

MM1:1/san
d/water

30%/67%/3%


1 d


0




B

MM1:1/sand/water

30%/67%/3%


1 d


0

0



C

MM1:1/sand/water

30%/67%/3%


7 d


10.5




D

MM1:1/sand/water

30%/67%/3%


7 d


9.7

10.1



E

MM1:1/sand/water

30%/67%/3%


30 d

12.6




F

MM
1:1/sand/water

30%/67%/3%


30 d

13.2

12.9












MM8b

A

MM4:3/ash/sand/wate
r

38%/12%/47%/3%


1 d


4.2




B

MM4:3/ash/sand/wate
r

38%/12%/47%/3%


1 d


4

4.1



C

MM4:3/ash/sand/wate
r

38%/12%/47%/3%


7 d


12.4




D

MM4:3
/ash/sand/wate
r

38%/12%/47%/3%


7 d


12.1

12.2











MM8c

A

MM1:1/ash/sand/w

26%/23%/46%/5%


1 d


0




B

MM1:1/ash/sand/w

26%/23%/46%/5%


1 d


0

0



C

MM1:1/ash/sand/w

26%/23%/46%/5%


7 d


3.1




D

MM1:1/ash/sand/w

26%/23%/46%/5%


7 d


4.9

4.0



E

MM1:1/ash/sand/w

26%/23%/46%/5%


30 d

4.1




F

MM1:1/ash/sand/w

26%/23%/46%/5%


30 d

4.0

4.0











MM10


A

MM1:1/CF

20%/80%


1 d


6

6








8 d


14

14




MM10

R

MM 1:1 / CF

20% / 80%


3 d

3 d


7 d

7 d

6.4

6.1

8.9

9.1



6.2


9.0











MM11

A

MM1:1/CF/ash/sludge

46%/22%/22%/8%


8 d


14

14




















MM12

A

MM2:1/ ash / water

55%/37%/8%



7 d


6.7




B




7 d


7.2




C




7 d


7.4

7.1











MM13

A

MM2:1/ ash / water

39%/47%/14%


7 d


19.5




B




7 d


20.6




C




7 d


18.2

19.4


LBJV TEST MIXES

January 2004


13

W.G. Rooke & Associates Ltd.


4.3:

LENGTH CHANGE RESULTS


ASTM standard C129 for
Non Load Bearing Concrete Bricks
requires that drying
shrinkage not exceed 0.065% from date of shipping of units from the manufacturing
site. Since no manufacturing procedure for such units has yet to be dete
rmined, none
of the cementitious test specimens were permitted to air dry and possibly undergo
initial shrinkage prior to re
-
saturation and subsequent length change measurement.
Air drying did occur with the single Mag
-
ment specimen. This is likely a “wors
t case
scenario” for drying shrinkage of cementitious mixes in the field since in practice,
some degree of air or oven drying and shrinkage of the units in stockpile may be
expected prior to shipping.


All length change tests were performed in accordance

with ASTM C426
-
99 as
required by ASTM C129. This test requires saturation of each test prism and then
precision oven drying under a standard humidity (17%) until no additional drying
shrinkage is detected.


During the tests, the technicians noted conside
rable emission of bubbles from the
cementitious mix specimens during submersion during the saturation phase of the
test. This would indicate a high porosity of the samples. Mass loss during drying in
the order of 5 to 6% for all cementitious mixes is ind
icative of this high rate of
absorption. The two Mag
-
ment samples had far less mass loss during drying, in the
order of 1.2% and did not exhibit significant bubbles during initial submersion.


The three cementitious mix designs and single Mag
-
ment mix sel
ected for length
change testing demonstrated adequate compressive strength to qualify as a non
-
load
bearing brick. Two specimens of each mix were tested.



Length Changes of Test Specimens


ASTM C426
-
99




Specimen Code

Linear Drying Shrinkage, %


Average

Mass loss, %


Saturation to constant mass



2A I



0.1992





5.27


2A II



0.16811




5.30



5S2 I



0.19005




5.21


5S2 II



0.21029




5.11



5A I



0.19246




6.26


5A II



0.20766




6.31



MM6C I


0.18529




1.20


MM6C II


0.18469




1.19

LBJV TEST MIXES

January 2004


14

W.G. Rooke & Associates Ltd.


5.0

DISCUSSION OF RESULTS:



5.1

CEMENTITIOUS MIXES:


These mixes labelled as cementitious are distinguished from those using Mag
-
ment in
that the chemical reaction and strength development of these mixes depends in whole
or in part on the chemic
al combination of the silicates in the lagoon ash and the
calcium oxide in the lime or Portland cement. Water is a necessary chemical
component of these cementitious mixes. Chemical reactions in the Mag
-
ment tests are
significantly different since silicat
es are not present and water, if used at all in Mag
-
ment mixes, is primarily a lubricant to enhance mixing.


These cementitious mixes are also distinguished from the Mag
-
ment mixes in that wet
curing is required for optimum strength development over time;
also the rate of
strength development is much slower. Many days (rather than hours) are required to
achieve sufficient strength for safe handling.


During fabrication, the cementitious test specimens were compressed under a
pressure of 1700 psi (11.7 MP
a) in a simulation of a brick manufacture apparatus.
They were then wet cured until the designated test date when they were saw cut into
cubes or prisms for testing.


ASTM C129 for
Non
-
Load Bearing Bricks
has two stipulations which must be met: (1)
the a
verage compressive strength of test specimens must be 4.14 MPa (with no single
specimen testing less that 3.45 MPa) and (2) drying shrinkage not exceed 0.065%.
Specimen cubes were tested in compression at 28 days and tabulated above. Drying
shrinkage test
ing was preformed on four selected mixes showing adequate strength
parameters.


Except for Mix 2S (which had insufficient paste), all cementitious mix designs satisfy
the
4.14 MPa strength criteria of ASTM C129. The highest strength was achieved (6.4
MPa)

by Mix 5A which utilized hydrated lime as the reactive agent with the lagoon ash.
The addition of VMA sand to these mixes (with the expectation that shrinkage potential
would be minimized) did, however, lower the reported strength 17 to 26%. Mix 2A,
usin
g 6% Portland cement with lagoon ash, achieved an average strength of 4.8 MPa.


Although not documented in these tests, it is highly likely that the rate of strength gain,
especially at early ages, would be higher with Portland cement mixes rather than w
ith
lime. This could be a significant consideration in the commercial manufacture of bricks
from these materials because it relates to the size and duration of inventory storage
and curing requirements.


None of the three mixes tested satisfied the leng
th change criteria for drying shrinkage.
Shrinkage rates exceeded the 0.065% rate by a factor ranging from 2.5 to 3.2. It should
be noted that none of the cementitious specimens had been air
-
dried after wet curing
such that no initial drying shrinkage wo
uld have had time to occur “in stockpile” prior to
LBJV TEST MIXES

January 2004


15

W.G. Rooke & Associates Ltd.

commencement of length
-
change testing. Air
-
drying did occur, however, with the Mag
-
ment specimen but this did not appear to influence the measured drying shrinkage.


ASTM C426
-
99 does not specify a par
ticular “field condition” for test specimens;
specimens tested in this program may be viewed as “the worst case scenario” since no
initial drying had been permitted to occur in the cementitious specimens. Future
specimens tested after air
-
drying [and pres
umably undergoing a degree of drying
shrinkage “in stockpile”] may demonstrate a satisfactory shrinkage rate. Time and
budget restricted demonstrating this either way.


5.2

MAG
-
MENT MIXES


The various Mag
-
ment mixes were batched in order to demonstrate
variations in
strength when a different filler, or combination of filler materials, was introduced in
various proportions into the Mag
-
ment slurry. The intent was to determine a
combination of materials in the mix which also exhibited acceptable strength
development and shrinkage characteristics.


The general observation when working with Mag
-
ment is the generally short time
available for batching of mixes and moulding of specimens, especially when the
recommended ratio of 2:1 for the dry and wet componen
ts of Mag
-
ment (MMd & MMw)
were adhered to. Initial mixes PMMA, PMMS and MM1 through MM3 were found to
stiffen very soon after batching, despite attempts to keep the Mag
-
ment liquid
component cold. This rapid setting initially inhibited the introduction
of significant
amounts of any filler material, resulting in high ratios of Mag
-
ment to fillers which in
practice would not likely be economical. In order to extend the pot life of the mixtures,
on the advice of LBJV, several mixes were batched with additi
onal amounts of the liquid
component (MMw) at ratios of 4:3 and 1:1. This assisted greatly in extending the
batching time, permitting higher volumes of fillers to be incorporated. Batching of mixes
MM12 and MM13 proceeded by blending all dry components (
filler + MMd) together
before adding any liquids. This did result in easier batching but is applicable only to
batches of pre
-
determined batch proportions.


MM1:

The second highest Mag
-
ment strength (60.7 MPa in 28 days) was recorded
for mix MM1, a

mixture of Mag
-
ment, lagoon ash and sludge. But because of the very
short batching time available, the filler materials constitute only 18% of the weight of the
batch. With 82% of the mix being Mag
-
ment, it is not likely to be economical. Rapid
stiffen
ing of the Mag
-
ment during batching did not permit additional filler to be added.


In later tests to increase the proportion of filler materials and improve workability, this
basic mix of ash, sludge and Mag
-
ment was rebatched. Mix MM1b was mix MM1 with
w
ater added. Strength development was slower and the recorded 31 day strength was
reduced to 23.9 MPa.


Mix MM1c maintained the same proportions of ash, sludge and water but altered the
MMd/MMw ratio to 4:3. It succeeded in reducing the proportion of Mag
-
ment downward
only marginally to 74.7 %. Again early stiffening during batching inhibited incorporating
more filler materials. Strength dropped further to 19.7 MPa at 31 days.

LBJV TEST MIXES

January 2004


16

W.G. Rooke & Associates Ltd.


But when the MMd/MMw ratio was altered to 1:1 (in mix MM1d), 42% of the mixtur
e
was now filler since batch time was more than tripled, early stiffening did not occur and
time was available to add more fillers. Strengths developed were an acceptable 18.6
MPa in 7 days and 24.6 MPa in 31 days.


MM2
: With 26% dry sludge alone as

the filler, this blend developed a 28
-
day
strength of 36.2 MPa. No supplementary tests were performed on this mixture since
the filler content was relatively low. However it is noteworthy that the sludge does not
appear to chemically interfere with stre
ngth development of Mag
-
ment as it was shown
to do in an earlier phase of this test program with cementitious mixes..


MM3 & MM4:

These two blends with approximately 25% lagoon ash and Mag
-
ment
alone differ only in the addition of water in MM4 in order
to simulate the fact that the
lagoon ash in stock
-
pile has a moisture content in the order of 25 to 30%. While the 28
-
day strength for the dry ash and Mag
-
ment combination tested at 44.3 MPa, this is not a
realistic combination because the ash was dry; dr
ying of the ash in the field would likely
be an uneconomical proposition. Utilization of ash with a simulated 30% moisture
content resulted in a drop on strength to 33.4 MPa; Mag
-
ment content remained high at
70%. Mix MM4 was a very pourable mix so addit
ional tests with even higher ash
contents were performed as Mixes MM4b and MM4c.


Addition of more damp ash in mix MM4b lowered the Mag
-
ment proportion somewhat to
61% but the short batch time of the 2:1 ratio Mag
-
ment inhibited the addition of more
fill
er. Strengths at 7 days dropped to 11.2 MPa and rose only marginally to 11.4 MPa by
31 days.


When the Mag
-
ment MMd/MMw ratio was altered to 1:1 (Mix MM4c) the quantity of
damp ash that could be added was greatly enhanced and the proportion of Mag
-
ment
red
uced to 28%. However, the 28
-
day strength development was negligible, dropping
to 3 MPa. The very small particle size and therefore high specific surface of the ash
likely inhibited coating of every particle by Mag
-
ment, greatly reducing the cementing
ef
fect. This, combined with the water and high MMw content, resulted in very low
strength development.


MM5

& MM6:

Sand was incorporated into the Mag
-
ment slurry for these specimens.
Again, the initial tests with a 2:1 ratio of MMd/MMw created a very sh
ort batch time for
both the dry and damp sand utilized.


The highest strengths attained for all of the Mag
-
ment blends tested (68.8 MPa @ 28
days) was mix MM5, incorporating 32% dry sand but an unacceptably high Mag
-
ment
fraction of 68%. Since any commerc
ial sand filler will likely be damp, mix MM6 and its
variances all included 5% moisture content in the sand. For MM6, this lowered the
strength to 58.8 MPa at 28 days.


Since the above two mixes were still very fluid when a pre
-
determined quantity of fil
ler
had been attained, subsequent variations proceeded with an excess of sand at hand
which was added to the Mag
-
ment slurry during batching. Additions continued until the
LBJV TEST MIXES

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W.G. Rooke & Associates Ltd.

mixture was too stiff for manual stirring. Mix MM6b managed to reduce the Mag
-
ment

component to 57%; mix MM6bb reduced the Mag
-
ment component still further to 51%.
The 28 day strengths were 21.6 MPa and 29.0 MPa for MM6b and MM6bb respectively.


In order to incorporate even more sand by extending the fluidity time of the slurry during

batching, mix MM6c was batched with the Mmd/MMw ratio of the Mag
-
ment altered to
1:1 from 2;1. In this manner, the Mag
-
ment ratio was reduced to 30%. This is
approaching the normal range for cementitious paste required in a sandy mortar of a
Portland cem
ent concrete and is likely as low a percentage of Mag
-
ment for a sand of
this fineness.


Altering the Mmd/MMw ratio in this manner cut the compressive strengths virtually in
half compared to the MM6b and MM6bb mixtures, dropping from approximately 20 MPa

at 7 days to 10 MPa. At 28 days, the strengths dropped from 21.7 MPa to 12.9 MPa.
Clearly, the increased use of the MMw component in order to enhance batching time
causes a significant loss of potential strength.


MM 7 & MM8:

A blend of lagoon ash
and sand was used in these mixes; water was
added to create MM8 from MM7 proportions, again simulating likely in
-
situ moisture
conditions for these fillers. When the initial batches again encountered rapid stiffening
during batching before significant qua
ntities of filler could be intermixed, the MMd/MMw
ratio was altered. Mix MM8b used a MMd/MMw ratio of 4:3 while mix MM8c used a
ratio of 1:1. The higher strengths were attained with the 4:3 ratio mixture.


Very high strengths (58 MPa) were recorded for
MM7 using dry materials. This
dropped to 44.6 MPa in MM8 when in
-
situ moisture contents were simulated by adding
water to the sand and ash. Again, because of early stiffening during batching, the Mag
-
ment proportion was unacceptably high at near 67% for
both mixtures. However, when
additional quantities of the moist sand/ash filler was added, reducing the Mag
-
ment
proportion to 38%, and the MMd/MMw ratio altered to 4:3 to enhance workability (mix
MM8b), strengths dropped to only 12 MPa
.
When the ratio w
as altered to 1:1 (thereby
enhancing workability still further and reducing the Mag
-
ment fraction to 26% (mix
MM8c)), the 28 day strength further to 4.1 MPa.


MM 10 & MM11:

The VMA sand used in the above tests provided the gradation which
yielded an acc
eptable texture to the test samples. The gradation of concrete sands
used in some earlier tests had not provided a smooth texture to the small brick and
cube specimens, so the VMA sand from a Brandon asphalt plant was substituted.


For any concrete mix, th
e least amount of cementitious paste is required when the
aggregate fraction exhibits a smooth gradation and the largest practical size of stone
compatible with the element being cast. Drying shrinkage is also minimized when a
larger aggregate size is use
d. With this in mind, a blend of aggregates with a14 mm
maximum size stone was selected for mixing with the Mag
-
ment. This aggregate blend
is known as Cold Feed and is more typically used in hot mix asphalt production.


When cold feed aggregates were us
ed alone in mix MM10 with a Mmd / MMw ratio of
1:1, the 8
-
day strength on the initial batch reached 14 MPa. However, when re
-
batched
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W.G. Rooke & Associates Ltd.

and tested at 7 days, the strength developed was only 9.0 MPa. Clearly, the reduced
MMd/MMw ratio and variations in batchi
ng had reduced the strength to much lower
levels than was expected.


When, in mix MM11, a combination of sludge, ash and cold feed aggregates were
incorporated into the Mag
-
ment, the fines in the sludge and ash appear to have soaked
up the Mag
-
ment and red
uced the overall quantity of filler that could be added. With a
Mag
-
ment proportion of 46%, the 8 day strength was only 14 MPa, the same as mix
MM10 but using much more Mag
-
ment.


MM12 & MM13
; Mixes MM12 and MM13 were added to the program after research
by
the Argonne National laboratory (ANL) in Illinois came to the attention of WGRA in
November. A paper published by ANL (Wagh, Jeong & Singh;
High Strength
Phosphate Cement Using Industrial Byproduct Ashes.
) provided strength test results for
mixes of ph
osphate
-
cement (similar to Mag
-
ment) with varying proportions of
commercial flyashes. Their program included both Class F and Class F ashes plus a
blend of the two.


ANL defined the “loading” of the ash as the percent of the total mass of the total powder

in the mixes, that is, the percent of ash relative to the dry component of the phosphate
cement. They had determined that mixtures which included approximately 50% to 60%
of the dry components as ash was optimum for strength development. Using this ANL
criteria as a guideline, WGRA mixes MM12 and MM13 to bracket those proportions.


Mix MM12 included a “loading” of lagoon ash of 50% of all dry components; Mix MM13
used more ash, at 65% of all dry components. For these two mixes, the batching
sequence wa
s altered such that all dry components (MM
d

+ ash) were thoroughly
blended together in the desired proportions prior to the addition of MM
w

and water. All
previous mixes had batched the MM
d

and MM
w

together first and then added the dry
components.


Althou
gh no time frame for testing was given in the ANL program, it would appear that
the resulting strengths attained with lagoon ash were less than half those achieved by
ANL when using commercial ashes. Mix MM13 did test at nearly 20 MPa in 7 days,
however.
The lower strengths are likely, in part, attributable to the 10% to 14% water
that had to be added to the mixtures to achieve workability. Strength tests at later ages
were not conducted on these two mixes because of time constraints in this phase of the
program.


In comparing strengths attained at various ash “loadings” in the WGRA program
compared to the ANL program, no optimal “loading” of 50% to 60% of the dry
ingredients as ash was evident, although such a loading would be relatively economical
to pro
duce. Comparison of MM13 with 65% ash to MM4 with 33% ash and to MM9 with
no ash at all demonstrates that strengths appear to drop as additional lagoon ash is
added. Mix MM9 which is 100% Mag
-
ment (0% ash loading) developed strengths of
27.1 MPa in 3 days
, compared with MM13 (65% ash loading) developing a strength of
20 MPa in 7 days.


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W.G. Rooke & Associates Ltd.

To be consistent in the tabulations above, the ”% loadings” of ash relative to the dry
component of Mag
-
ment, MM
d
, are not directly shown; instead, the tabulation is
consis
tent with the other mixes, showing percentage of the total batch mass for each
component.



5.3

ONGOING TESTING


Two small “brick” specimens of Mag
-
ment mixes have been forwarded to the INCO
refinery in Thompson for long term exposure to the hot acid envir
onment there. This
test will be qualitative in nature in order to demonstrate whether or not the Mag
-
ment
can better withstand chemical attack in this extreme environment.


Specimens were cast, and remain in ENG
-
TECH’s lab, which could be used in future
t
est programs to demonstrate freeze
-
thaw durability [mix MM11] and chloride
permeability [mixes MM6c, MM6bb, MM10R and MM 8c.]. Budget and time constraints
did not permit these additional tests to proceed at this time; they had not been
contemplated in the

original proposal by WGRA but could be included in any future
program.



6.0

CONCLUSIONS


6.1

CEMENTITIOUS MIXES


Except for one mix where insufficient paste was developed, all cementitious mixes
tested satisfy the minimum strength criteria for ASTM C129
for
Non
-
Load Bearing
Bricks.

However, under the “worst
-
case scenario” test conditions selected here, none
of the specimens satisfied the drying shrinkage criteria in ASTM C129. Future length
change testing would be necessary to determine whether or not p
re
-
conditioning prior
to testing in order to mimic days of air
-
drying and probable drying pre
-
shrinkage “in
stockpile” would yield test specimens that satisfy this second criteria.


6.2

MAG
-
MENT BLENDS


All but two of the Mag
-
ment blends satisfy the minimu
m strength for ASTM C129. A
representative mix (MM6c with a high proportion of sand) was selected for length
change testing. It demonstrated shrinkage comparable to the cementitious mixes
(approximately 0.20 %) and therefore failed to satisfy the dryi
ng shrinkage criteria of
ASTM C129. It was assumed that this sandy mix would be least likely to shrink but
other Mag
-
ment mixes were not tested for drying shrinkage.


The blends batched and tested which included high proportions of damp ash or an
ash/sand

blend (mixes MM4c and MM8c) just managed to meet the brick strength
criteria while utilizing the least amount of Mag
-
ment (28% and 30%). The mix with the
lowest Mag
-
ment fraction (MM10 @ 20%) included the cold feed aggregate whose
particle size was 14 mm.

This demonstrates that a larger maximum aggregate size
LBJV TEST MIXES

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W.G. Rooke & Associates Ltd.

yields a mix with less cementitious paste required. The 8
-
day strength for MM10 of only
14 MPa may, however, be a limitation for many applications. Strength at other test
ages was not determined for

this mix.


The fine particle size within the ash and sludge in particular are a limitation during
batching since their very small particle size and corresponding high specific surface
area demands a high liquid content in order that all faces of these par
ticles are coated.
The high demand for either water or MMw prompts reduced strength.


Mix MM3, with ash only added to Mag
-
ment, developed significantly higher strengths
when compared to mix MM2 (with sludge only added to Mag
-
ment). The blend of ash
and

sludge (mix MM1) developed even higher strengths.


Since many of the Mag
-
ment blends greatly exceed the 4.14 MPa strength requirement
for non load bearing bricks, other applications for some of these mixes should be
pursued. WGRA has provided LBJV with co
pies of ASTM Standards (page 25) relating
to several possible products. Many blends provided strengths well above 20 MPa at 28
days which would be considered a minimum strength for many of these other
applications. In the future, durability and related
absorption tests on selected mixes
would be recommended as required by several of these standards. Because of their
characteristic high early strength gain, Mag
-
ment mixes should be considered for
specialty applications such as rapid repairs and certain p
recast elements.


Several of the blends (MM1 with ash/sludge filler and MM4 with a sand filler) attained
extremely high strengths, over 60 MPa. However, when the MMd/MMw ratio was held
to 2:1, the Mag
-
ment fraction (82% and 68%) remained high. Similar ba
tches with
adjusted MMd/MMw ratio intended to incorporate a higher proportion of filler provided
much lower strengths, likely because of the high MMw content required to coat this
additional material.


Since the short batching “window” available was often

a significant limitation on the
quantity of filler material (dry ingredients such as ash, sludge, cold feed aggregate or
sand,) that could be incorporated, the Mag
-
ment reaction often had to be retarded
significantly by altering the MMd/MMw ratio. Howev
er, invariably, significant loss of
strength occurred by this dilution of the Mag
-
ment as noted above. Future testing of
selected mixes should consider extending the available batching time by the use of
other chemical retarders, such as borax, which may
well permit addition of much more
filler to these mixes. While some loss of strength may result, it may well be less than
that experienced in these tests when the retardation was effected by the use of more of
the liquid component of the Mag
-
ment. Alter
natively, batching apparatus more typical
of that recommended for commercial production with these cements should be
acquired.


Respectfully submitted,



Wally Rooke, P.Eng

W.G. Rooke & Associates Ltd.

LBJV TEST MIXES

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21

W.G. Rooke & Associates Ltd.



APPENDIX A


Mix Designs


A1:

Mixes utilizing Por
tland cement or lime as the lagoon ash
activator and binder.



Sufficient water added to each mix to create high slump; excess water expelled by
compression within mould.



Mix Design # 2A



6% cement + Lagoon ash

Lagoon ash, gross: ............ g

Dry lago
on ash




5000 g

Portland Cement






300 g


Mix design # 2S



Cement/ash paste per Mix 2A plus VMA sand

Oven dry sand





4000 g

Lagoon ash, dry =




1200 g

Cement @ 6% = .06 X 1200 =



72 g


Mix design # 2S2



6% Cement, 30% lagoon as
h and VMA sand

Damp sand






4000 g

Lagoon ash, dry =




1200 g

Cement @ 6% = .06 X 5200 =



312 g


Mix design 5A



Lagoon ash + lime (Ash/lime @ 4:1)

Dry ash =






5000 g

Lime added =







1250 g


Mix design # 5S1

VMA sand and blend of
Lagoon ash and lime @ 4:1 ratio

Ash/sand ratio @ 1:1.

Dry lagoon ash




3000 g

Hydrated lime:






750 g .

Dry sand:






3000 g


Mix design # 5S2

VMA sand and blend of Lagoon ash and lime @ 4:1 ratio

Ash/sand ratio @ 2:1

Dry lagoon ash:




300
0 g

Hydrated lime:





750 g

Dry sand:





1500 g



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W.G. Rooke & Associates Ltd.

APPENDIX A2 MAG
-
MENT MIXES


The percentage of each component (by mass) is indicated for each mix design.



MM 1:


Blend Ash / sludge / MM:

Lagoon ash dry



(11%)





291 g

Ferrous Sulphate Sl
udge, dry

(7%)





194 g

Mag
-
ment




(82%)


MM dry

1500 g



`





MM wet


750 g

Ash/sludge was blended to 3/2 proportions. Mag
-
ment @ 2:1 dry/wet ratio.

Mix rapidly became a stiff dough requiring tamping into moulds.



MM 2:


Blend Sludge / MM:

Sludge
, dry





(26%)





800 g

Mag
-
ment





(74%)


MM dry

1500 g








MM wet @ 4
o
C 750 g

Mag
-
ment @ 2:1 dry/wet ratio.



MM 3:



Blend Ash / MM:

Lagoon ash, dry



(25%)





750 g

Mag
-
ment, 75%




(75%)



MM dry

1500 g








MM wet


750 g

Mag
-
ment @
2:1 dry/wet ratio.

Mix very stiff needing tamping into moulds. Rapid set.



MM 4:



Blend Ash / MM / water

Lagoon ash




(23%)





750 g

Water





(7%)





225 g

Mag
-
ment




(70%)


MM dry

1500 g








MM wet 3
o
C


750 g

Mag
-
ment @ 2:1 dry/wet ratio.

V
ery fluid mix
-

pourable. (Could have absorbed more ash)



MM5:



Blend Sand MM: 32% sand:45% MMd:23% MM w

VMA Sand, dry



(32%)





1050 g

Mag
-
ment




(68%)


MM dry


1500 g








MM wet


750 g

Mag
-
ment @ 2:1 dry/wet ratio.

Fluid mix, no tampin
g required. (Could have absorbed more sand.)

Slightly better texture noted with dry sand (MM5) compared to dry ash (MM3)




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W.G. Rooke & Associates Ltd.

MM6



Blend Damp sand and MM

VMA Sand @ 5% mc



(37%)




1352 g

Mag
-
ment




(63%)


MM dry

1500 g








MM wet


750 g

Mag
-
ment @ 2
:1 dry/wet ratio.

Fluid mix, no tamping needed.


MM 7:



Blend Ash/Sand/MM

Ash, dry




(6%)





200 g



VMA Sand, dry



(25%)





800 g

Mag
-
ment




(69%)


MM dry

1500 g








MM wet


750 g

Mag
-
ment @ 2:1 dry/wet ratio.


MM8:



Blend damp Ash/Sand/MM

Ash



(6%)







200 g

VMA Sand


(24%)







800 g

Water



(3%)







100 g

Mag
-
ment


(67%)




MM dry

1500 g








MM wet


750 g

Mag
-
ment @ 2:1 dry/wet ratio.



MM9:



MM neat

Mag
-
Ment


(100%)




MM dry

2000 g








MM wet

1000 g


Mag
-
ment @ 2:1 d
ry/wet ratio.

Concave shrinkage noted in specimens with lesser degree of concavity in specimens fabricated
last



LBJV TEST MIXES

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W.G. Rooke & Associates Ltd.

SUPPLEMENTAL MAG
-
MENT MIXES


MM1b:



Enhanced workability of MM1 mix by addition of water.

Lagoon ash, dry

(15.7 %)






450 g

Water



( 4.
7 %)






135 g

Sludge, dry


(10.5 %)






300 g

Mag
-
ment


(78.5 %)




MM d

1500 g


MM w


750 g

Mag
-
ment @ 2:1 dry/wet ratio.


MM1c:


As above with additional MM w

Lagoon ash, dry

(12.8 %)






450 g

Water



( 3.8 %)






135 g

Sludge, dry


( 8.5 %
)






300 g

Mag
-
ment


(74.7 %)



MM d


1500 g


MM w


1125 g

Mag
-
ment @ 4:3 dry/wet ratio.


MM1d:


As above with MM ratio altered to 1:1 d/w:

Lagoon ash, dry

(31%)






1049 g

Sludge



(10%)







349 g

Mag
-
ment


(58%)




MM d


1000 g


MM w


1000 g

Mag
-
ment @ 1:1 dry/wet ratio.


MM4b:


MM4 modified with additional ash

Lagoon ash, dry

(30%)






1125 g

Water



( 9%)







338 g

Mag
-
ment


(61%)




MM d


1500 g


MM w



750 g

Mag
-
ment @ 2:1 dry/wet ratio.


MM4c:


Additional ash and modified MM ratio to

1:1

Lagoon ash, dry

(55%)






4000 g

Water



(17%)






1200 g

Mag
-
ment


(28%)




MM d


1000 g


MM w


1000 g

Mag
-
ment @ 1:1 dry/wet ratio.


MM6b:



MM 6 with additional VMA sand.

VMA Sand, dry

(41%)






1650 g

Water



( 2%)







83 g

Mag
-
ment


(57%
)




MM d


1500 g


Mm w



750 g

Mag
-
ment @ 2:1 dry/wet ratio.


MM6bb:


Additional sand to MM6b

VMA Sand, dry

(46%)






2020 g

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W.G. Rooke & Associates Ltd.

Water



( 2%)







101 g

Mag
-
ment


(51%)




MM d


1500 g


MM w



750 g

Mag
-
ment @ 2:1 dry/wet ratio.


MM6c:


Altered MM rat
io

VMA Sand, dry

(67%)






4468 g

Water



( 3%)







223 g

Mag
-
ment


(30%)




MM d


1000 g


MM w


1000 g

Mag
-
ment @ 1:1 dry/wet ratio.


MM8b:



Modified MM8 with additional ash and sand; (still soupy)

Lagoon ash, dry

(12%)







400 g

VMA Sand, dry

(4
7%)






1600 g

Water



( 3%)







100 g

Mag
-
ment


(38%)




MM d



750 g


MM w



563 g

Mag
-
ment @ 4:3 dry/wet ratio.


MM8c:


Modified above with additional sand and ash

Lagoon ash, dry

(23%)






1760 g

VMA Sand, dry

(46%)






3520 g

Water



( 5%)







400 g

Mag
-
ment


(26%)




MM d


1000 g


MM w


1000 g

Mag
-
ment @ 1:1 dry/wet ratio.


MM10:


Mix incorporating 14 mm aggregate blend (Cold feed, CF)

Cold Feed (CF) aggregates prepared for Borland Set 2 asphalt mix


CF (mc 3%)


(80%)






7961 g

Mag
-
m
ent


(20%)




MM d


1000 g


MM w


1000 g

Mag
-
ment @ 1:1 dry/wet ratio.


LBJV TEST MIXES

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W.G. Rooke & Associates Ltd.

MM11:


Cold Feed (CF) aggregates added to ash/sludge blend

100 mm cylinder and F/T slab cast.


CF(mc 3%)


(22%)






2100 g

Ash, dry


(22%)






2100 g

Sludge, dry


( 8%)







750
g

Mag
-
ment


(46%)




MM d


2200 g


MM w


2200 g

Water (added late to enhance workability and moulding of slab.)


300 g



Mag
-
ment @ 1:1 dry/wet ratio.


MM12



MM + ash;
[ash 50% powder]

dry components blended first


Ash




(36%)






460 g

Mag
-
ment



(55
%)



MMd



460 g


MMw



230 g

Water [23% of ash content]

(9%)






106 g


MM13



MM + ash;
[ash 65% powder]

dry components blended first.


Ash



(47%)







460 g

Mag
-
ment


(39%)




MMd



248 g

MMw



125 g

Water (30% of ash content) (14%)






13
8 g


These latter two mixes were batched such that the “% powder” for the ash was 50%
and 65% respectively; dry ingredients were blended first before liquids added. This mix
format was that used by the Argonne lab test program.





















LBJV TEST MIXES

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W.G. Rooke & Associates Ltd.


APPEND
IX A3




ASTM Designation:
C 936
-

96

Standard Specification for Solid Concrete Interlocking


Paving Units


ASTM Designation:
C 90
-

01

Standard Specification for Loadbearing Concrete



Masonry Units
1



ASTM Designation:
C 55
-

01

Standard Specification for Concrete Brick
1


ASTM Designation:
C 62
-

00

Standard Specification for Building Brick (Solid



Masonry Units Made From Clay or Shale)
1


ASTM Designation:
C 56
-

96

Standard Specification for Structural Clay


Non
-
Load
-
Bearing Tile
1


ASTM Designation:
C
73
-

99a

Standard Specification for Calcium Silicate Brick


(Sand
-
Lime Brick)
1





























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