PRODUCTION AND PROPERTIES OF WOOD-CEMENT BOARDS

FROM MACARANGA GIGANTEA

ABSTRACT

Wood-cement board (WCB) is a panel product that has the advantages of inorganic and

organic materials. However, the main problems affecting the manufacture and use of WCB are

the inhibitory effects of wood on the setting of cement and the high specific gravity of the final

product. This paper examines the potential and the use of additives that was use to facilitate

the production of a WCB from Macaranga gigantea. Wood cement boards (WCB) were

manufactured with wood/cement (w/w) ratio of 1:2.5, target density is 1300kg m -3 and Al2 (SO4)3

and Na2 SiO3 content as chemical additives is 1.5% and 3.0% . The WCB were tested for static

bending (MOR and MOE) properties in parallel (//) and perpendicular (┴) directions; internal

bond (IB), thickness swelling (TS) and water absorption (WA).

1. INTRODUCTION

Wood-cement boards (WCB) are already used thoroughly in Europe, United States, Russia

and S.E. Asia, mainly for roofs, floors and walls. They possess countless advantages compared

to panels produced with organic resins which are high durability, good dimensional stability,

acoustic and thermal insulation properties and low production cost. In recent years, several

research groups have been evaluating the suitability of different lignocellulosic materials for the

manufacture of WCB including cypress (Okino et al. 2005), rubberwood (Okino et al. 2004),

eucalyptus (Okino et al. 2004; Evans et al. 2000; Del Menezzi and Souza, 2000; Latorraca,

2000), pines (Cabagon et al. 2002; Teixeira and Pereira, 1987), acacia (Eusebio et al. 2002;

Teixeira and Guimarães, 1989), agricultural residues (Almeida et al. 2002) and fiber (Del

Menezzi etal. 2001). In spite of these studies there is no industrial plant in Brazil yet.

There are obstacles to the utilization of these materials for WCB. The main problems are the

inhibitory effect caused by wood on the cure of cement and the high density of the final product.

Wood component, mainly extractives and polysaccharides, affects reactions between wood and

cement resulting in boards of low quality. Jorge et al. (2004) argued that the nature of the

extractives also has influence on this inhibitory effect.

To solve inhibition problems, it is common to add inorganic chemicals, known as

accelerators, to accelerate the cure of cement or use pretreatments such as aqueous extraction

to remove inhibitory substances from wood. Cement chemicals accelerators usually improve the

properties of WCB (Jorge et al. 2004).

The objective of this project was to assess whether it is possible to manufacture a WCB

with suitable mechanical properties. Three factors were varied during the manufacture of boards

to produce composites with desired properties: low wood cement ratio to reduce board density

and distribution to improve board strength/stiffness and off sett the effect of low board density.

2. MATERIAL AND METHOD

2.1 Wood Material

Species of wood that use in producing the WCB is Macaranga gigantea’s top part from forest

learning of UiTM Pahang were felt cause of lightning. The age of the tree is undefined. The first

logs were cut on the spot it felt which was cut into three section; top, middle and bottom

transported to the workshop by backhoe.

2.2 Particle Preparation and Board Production

Actually, manufacture of wood cement board (WCB) in early stage is a bit similar as

particleboard manufacture. The different will be take a look during mixing stage. Wood cement

board mix wood, cement that is Portland and chemical additives that is aluminum sulphate

[Al2(SO4)3]. Before proceed to the process of mixing WCB at Figure 1.6 the important thing that

to be know is the flow chart of wood cement board production.

Flow chart of wood cement board production

Wood chipper flaking wood particle mixing

Hardening chamber compressing Mat forming

Curing cement bounded particle board testing

Figure 1.6

Next step is to take the mixer for mat forming process. This process is to get the mixture to a

mould. Same with particleboard, this process is to reduce the thickness of the mould. The mould

then send to hardening chamber for hardening the board. It is stay inside hardening chamber

about 24 hours. Figure 1.7 shows the process during WCB in hardening chamber.

Figure 1.7

After the board is taken out of hardening chamber, it will be dried for about three month for the

board to completely hardening. Lastly, the board will be test to know it strength properties.

Figure 1.8 shows the testing of WCB.

Figure 1.8

Figure 1.9 shows that WCB is prepared for testing

Figure 1.9

WOOD CEMENT BOARD

Cement calculation

Target density = 1300kg m-3

Ƿ = mass (m)volume (v)

Volume of mould =[450mm × 450mm× 10mm3]

M = Ƿ. volume ¿

= 1300×2.025×10-3

M = 2.6325kg/2632.5g

Total weight of dry cement board

Example : to calculate cement board of ratio

Let χ = oven dry wood

= 1χ + 2.5 (cement)χ + (0.015 × 2.5)χ + (0.03 × 2.5)χ

= m(2632.5g)

χ + 2.5χ + 0.0375χ + 0.075χ = 2632.5

3.6125χ = 2632.5

Oven dry wood→ χ = 728.72g

Cement is = 2.5χ

= 2.5× 728.72

= 1821.8g

Chemical additives

Al2 (SO4)3 = 1.5% × 2.5χ

= 27.327g

Na2 SiO3 = 3.0%× 2.5χ

= 54.654g

*note : all chemical additives concentration was prepared@10% let MC of wood = 16%

Material Dry weight/g H2O weight/g Air dry

weight/g

Additional/g Total

Wood 728.72 +@16%

=116.595

845.315 + 42.266 887.581

Cement 1821.8 + 0 1821.8 + 91.09 1912.89

Al2 (SO4)3 10%

27.327

90%

+245.943

100%

273.27

+ 13.674 286.934

Na2 SiO3 10%

54.654

90%

+491.886

100%

546.54

+ 27.327 573.867

Total 2632.501 854.424

Based on MC = 45% ← assume that the MC of wood cement board

Raw cement board = 1184.626 – 854.424

Total weight

H2O in system

2632.501 ×45100

=330.202g←actual quantity of water that will be added in the system

Wood cement ratio

1:2.0

1:2.25

1:2.5

1:2.75

1:3.0

Type of cement is Portland cement

Standard use to test =MS 544 (200)

MOR MOE WA TS IB

≥9.0mp ≥3000mpa ≤30% ≤2% ≥0.5 in pa

Cutting plan for testing

BENDING

←B1,B2,B3,B4,B5

Length= 175mm

Total quantity of water in wood cement

B1

B3

B2

B4

B5

TS1 IB

TS2

TS3

IB3

IB

IB

B

Width = 100mm

←TS1,TS2,TS3

Length= 100mm

Width = 100mm

Length =50mm

Width =50mm

Mould of wood cement board

Length= 450mm

Height= 450mm

Thickness= 10mm

1 board, m = 2632.5g

Wood + cement + H2O + additives = 2632.5g

*note : additive must be below than 5%,if it is above 5% instability molecule would happen and

5% taxable exaggerating of wood,cement,H2O and additives to prevent error during mixing.

Result

Wood cement board : Size particle that use to produce wood cement board is 2.0, 1.0 and 0.5

Bending test

Particle size 2.0

Width Thickness Length Weight Density Maximum MOR MOE

TS

IB

MOR & MOE = 175mm × 100mm

Density & TS/Wa = 100mm × 100mm

IB = 40mm × 40mm

P=1300

Aluminium sulphite[ Al2 (SO4)]

- For harden the mixture

Sodium silicate[ Na2 SiO3]

- For improve bonding

(mm) (mm) (mm) (g) (kg/m3) load

(kN)

(MPa) (MPa)

1 103.50 13.60 175.90 251.820 1016.91 0.82 9.69 2243.77

2 101.42 14.83 176.07 271.650 1026.07 0.96 9.71 2796.47

3 102.76 11.82 175.68 254.286 1191.37 0.82 12.79 3478.86

4 101.21 12.81 174.78 276.036 1217.77 1.11 15.07 4172.01

5 100.88 13.59 177.36 256.839 1056.36 0.82 9.89 2106.25

Mean 101.95 13.33 0.00 0.00 1101.70 0.91 11.43 2959.47

S.D. 1.12 1.11 0.00 0.00 95.50 0.13 2.42 867.01

Minimum 100.88 11.82 0.00 0.00 1016.91 0.82 9.69 2106.25

Maximum 103.50 14.83 0.00 0.00 1217.77 1.11 15.07 4172.01

Range 2.62 3.00 0.00 0.00 200.86 0.30 5.38 2065.77

Particle size 1.0

Width

(mm)

Thickness

(mm)

Length

(mm)

Weight

(g)

Density

(kg/m3)

Maximum

load

(kN)

MOR

(MPa)

MOE

(MPa)

1 101.69 12.83 174.96 208.932 915.01 0.38 5.07 1138.57

2 98.18 14.08 175.22 218.375 901.69 0.42 4.80 1163.83

3 101.32 12.05 176.06 205.130 954.07 0.33 4.97 1606.26

4 97.99 12.27 174.52 207.423 988.20 0.41 6.19 1462.94

5 99.95 14.97 175.87 256.262 973.71 0.63 6.31 1301.47

Mean 99.83 13.24 0.00 0.00 946.53 0.43 5.47 1334.61

S.D. 1.72 1.25 0.00 0.00 37.20 0.12 0.72 199.34

Minimum 97.99 12.05 0.00 0.00 901.69 0.33 4.80 1138.57

Maximum 101.69 14.97 0.00 0.00 988.20 0.63 6.31 1606.26

Range 3.70 2.92 0.00 0.00 86.51 0.30 1.51 467.68

Particle size 0.5

Width

(mm)

Thickness

(mm)

Length

(mm)

Weight

(g)

Density

(kg/m3)

Maximum

load

(kN)

MOR

(MPa)

MOE

(MPa)

1 101.66 12.97 175.64 259.412 1119.98 0.65 8.56 2603.98

2 101.62 13.96 175.46 291.662 1171.76 0.87 9.87 3050.91

3 99.69 12.77 175.34 296.90 1329.90 0.48 6.57 2631.87

4 101.57 13.59 175.84 286.888 1182.41 0.81 9.76 3278.05

5 100.09 13.85 177.53 274.007 1113.80 0.69 8.13 2459.28

Mean 100.93 13.43 0.00 0.00 1183.57 0.70 8.58 2804.82

S.D. 0.96 0.53 0.00 0.00 87.57 0.15 1.35 344.29

Minimum 99.69 12.77 0.00 0.00 1113.80 0.48 6.57 2459.28

Maximum 101.66 13.96 0.00 0.00 1329.90 0.87 9.87 3278.05

Range 1.97 1.19 0.00 0.00 216.10 0.39 3.29 818.77

MOR mean for the particles

2.0 = 11.43 MPa

1.0 = 5.47 MPa

0.5 = 8.58 MPa

Graph shows mean for bending wood cement board

mean for bending wood cement board0

2

4

6

8

10

12

14

size 0.5size 1.0size 2.0

Internal bonding (IB) test

Particle size 2.0

Weight( g )

Length( mm )

Thickness( mm )

Width( mm )

Density(kg/m3)

Maximum load ( N )

IB( MPa )

1 28.561 13.92 40.55 39.67 1275.87 397.38 0.722 26.123 14.11 40.98 39.24 1151.48 683.35 1.233 29.909 15.11 42.44 41.55 1122.88 545.94 0.874 28.326 13.93 42.20 41.52 1160.30 408.73 0.71Mean 0.00 14.27 41.54 40.50 1177.63 508.85 0.88S.D. 0.00 0.57 0.92 1.21 67.41 134.50 0.25C.V. 0.00 3.97 2.21 3.00 5.72 26.43 27.86Range 0.00 1.19 1.89 2.31 152.98 285.97 0.53

Particle size 1.0

Weight( g )

Length( mm )

Thickness( mm )

Width( mm )

Density(kg/m3)

Maximum load ( N )

IB( MPa )

1 24.799 14.72 40.15 40.49 1036.11 318.79 0.532 29.668 15.52 41.14 41.17 1128.48 382.84 0.603 29.629 14.84 38.95 40.70 1259.62 468.24 0.784 29.441 14.39 40.50 40.04 1262.10 380.23 0.66Mean 0.00 14.87 40.19 40.60 1171.58 387.52 0.64S.D. 0.00 0.48 0.92 0.47 109.78 61.41 0.10C.V. 0.00 3.21 2.29 1.16 9.37 15.85 15.94Range 0.00 1.14 2.19 1.13 225.99 149.45 0.24

Particle size 0.5

Weight( g )

Length( mm )

Thickness( mm )

Width( mm )

Density(kg/m3)

Maximum load ( N )

IB( MPa )

1 22.759 14.27 41.18 33.57 1153.94 290.69 0.612 23.829 14.16 38.74 34.02 1277.24 778.75 1.623 19.851 14.44 41.06 39.11 856.07 624.48 1.114 16.724 14.23 40.72 41.37 697.76 559.38 0.95Mean 0.00 14.27 40.43 37.02 996.25 563.33 1.07S.D. 0.00 0.12 1.14 3.83 266.19 203.71 0.42C.V. 0.00 0.85 2.82 10.37 26.72 36.16 39.25Range 0.00 0.28 2.44 7.80 579.48 488.05 1.01

IB mean for the particles size:

2.0 = 0.88 MPa

1.0 = 0.64 MPa

0.5 = 1.07 MPa

Graph show mean for IB wood cement board

mean for internal bonding wood cement board0

0.2

0.4

0.6

0.8

1

1.2

size 0.5size 1.0size 20

Thickness swelling test

Average Tensile Strength for Wood Cement Board.

Weight Thickness

0.5mm 160.004 12.889

1.0mm 157.918 12.804

2.0mm 149.091 12.991

Graph for Tensile for WCB

weight thickness0

20

40

60

80

100

120

140

160

180

size 0.5size 1.0size 2.0

REFERENCES

www.scielo.cl/pdf/maderas/v9n2/art_01.pdf

www.mtc.com.my/info/index.php?option=com_content&view=article&id=511:plywood-

blockboard-clipboard-wood-cement-board-woodwool-slabs-and-other-

boards&catid=48:carpentry-joinery-and-iron-mongery-works&Itemid=89

zentechecoboard.com/documents/Installation%20manual%20of%20Wood%20Cement

%20Board.pdf

fr.wikipedia.org/wiki/Fichier:Macaranga_gigantea_-_mahang_gajah.JPG

www.slideshare.net/search/slideshow?

type=presentations&q=WOOD+CEMENT+BOARD+MANUFACTURE&searchfrom=bas

ic

Exterior Plaster Wall and Ceilings, Fire-Resistive & Drywall Assemblies:Presented by the Technical Services Information Bureau ;Darin Coats,Bryan Stanley and Michael M. Logue

Journal Of Electrical Engineering, Vol. 62, No. 1, 2011, 25–30 Microwave Electromagnetic Filed And Temperature Distribution In A Multilayered Wood{Cement Board by Jaroslav Franek

CMU. Journal (2006) Vol. 5(2) ,Sustainable Supply Chain of Construction Products and Materials: A Case Study of Natural - Fiber Cement Wall Products by Poon Thiengburanathum, Vitul Lieorungruang, Ampan Bhromsiri and Wassanai Wattanutchariya