1) The study evaluated the effect of different levels of marble dust as cement replacement in concrete hollow blocks (CHB) on physical and mechanical properties. 2) Marble dust was collected from waste sites and used at levels of 0-20% cement replacement. Testing showed 10% replacement produced CHBs with optimal compressive strength and water absorption. 3) Compared to commercial CHBs, 10% marble dust CHBs met strength standards, had lower water absorption, and were estimated to provide annual net income of over $2,500 based on reduced production costs. 4) Using marble dust from waste as a partial cement replacement in CHBs was concluded to provide environmental and economic benefits.

1. EFFECT OF DIFFERENT LEVEL OF MARBLE
DUST AS CEMENT REPLACEMENT IN
THE PHYSICAL AND MECHANICAL
PROPERTIES OF CONCRETE
HOLLOW BLOCKS (CHB)
Kristine Mae G. Castillon, Shiermagne M. Gańo
Carol G. Macabasag, Mark Gil G. Mendoza
Kate Danielle G. Perez and, Rolando P. Javellonar

2. BACKGROUND OF THE STUDY
 Marble processing is gaining popularity due to increase
in its usage in construction industry.
 Today, almost all the modern architectural designs of
houses and plazas include the final touch of beautiful
shades of marble in exterior as well as interior portions.
 One of the major waste generating industries is the
marble quarry and production industry by which around
70% of this precious mineral resource is wasted in the
mining, processing, and polishing procedures.
 Around 40% of marble waste is generated worldwide
during quarrying operations in the form of rock
fragments
 Marble wastes are being dumped either in nearby pits,
roads, riverbeds, pasturelands, landfills and agricultural
fields leading to widespread environmental pollution
(Çelik, 1996; Akbulut and Gürer, 2003).

3. BACKGROUND OF THE STUDY
 Marble is the most significant mineral deposit of
Romblon and is the most renowned product of the
province.
 Based on statistics, Romblon is the second biggest
provincial marble producer of the country next to
Bulacan.
 Romblon marble is of very high quality and comes in
shades of white, green, pink, red and black.
 The Mines and Geosciences Bureau has estimated that
Romblon is endowed with about 150 million metric tons
of marble.
 At current rates of extraction, the supply may last for
three more centuries.
 Tablas Island is also believed to have vast reserves of
marble (PSA, 2013).

4. BACKGROUND OF THE STUDY
 While it is a promising industry, processing of marble
results in the formation of marble dust which is
suspended in the air and may then be inhaled by the
workers.
 Epidemiological studies indicates that workers exposed
to marble dust have higher risk of suffering from asthma,
chronic bronchitis, nasal inflammation and impairment
of lung function.
 In order to minimize health hazard as a result of
processing marble, marble dust should be collected and
recycled into value added product.
 The recycling of marble dust will not only prevent
pollution but also minimize if not totally eliminate hazard
to human health.
 It is in this context that this research study was
undertaken.

5. OBJECTIVES
Generally, the study aimed to determine the effect of
different levels of marble dust as cement replacement in the
physical and mechanical properties of concrete hollow
blocks (CHB).
Specifically, the study aimed to:
• Determine the effect of marble dust as cement
replacement in the compression strength of CHB
• Determine the effect of marble dust as cement
replacement in the water absorption capacity of the
developed CHB
• Compare the CHB with marble dust admixture to
commercial CHB in terms of physical and mechanical
properties.
• Determine simple cost analysis in the production of the
marble dust CHB

6. Significance of the Study
 Lessen pollution and waste produced by marble
industries, hence, advocating an eco-friendly
environment
 Serve as benchmark information and guide for further
research and development
 Source of additional income and livelihood project in
the community
Scope and Delimitation
 The study focused only in determining the effect of
different level of marble dust as cement replacement in
the physical and mechanical properties of 4”x8”x16”
CHB such as water absorption capacity and
compressive strength.
 Furthermore, mixing preparation and ratio of cement to
sand/gravel was based only on one CHB manufacturer
in the municipality of Odiongan, Romblon.

7. Conceptual Framework
INPUT
Marble Dust
Cement
Sand
Water
PROCESS
Collection of Marble Waste
Recovery of Marble Dust
through Colloidal
Suspension
Preparation of Mixture
Mixing, Molding, Curing
Physical and Mechanical
Property Test
OUTPUT
Concrete
Hollow blocks
with marble
dust
Figure 1: Conceptual Framework

8. METHODOLOGY
 Interview with marble processor was undertaken to
gather data and relevant information necessary in the
conduct of the study.
 Marble waste was collected from dumped sites and
landfills in Barangay Cajimos, Romblon, Romblon.
 Marble dust was recovered by means of colloidal
suspension.
 Hollow blocks was prepared following the procedure in
making commercial CHB in the locality using the
proportion specified in the treatment.
 Newly formed CHBs were cured for 14 and 28 days for
compressive strength test (based on the specimen’s
sensitivity to loading rate: ASAE Standard, 1997) and
 Water absorption test in accordance to ASTM C 642-82
after 28 days of curing.
 Comparison of CHB with marble dust against commercial
CHB in the locality was undertaken

9. COMPRESSIVE STRENGTH
The compressive strength was calculated using
equation (1).
𝒇𝒄 =
𝒑
𝒂
eq. (1)
where:
𝒇𝒄= compressive strength in MPa
p= compressive load causing failure in N
a= cross sectional area in 𝒎𝒎𝟐

10. WATER ABSORPTION TEST
Water absorption test was done to determine the
permeability characteristics of a certain material
commercial CHB and the CHB with marble dust. The
percentage absorption was calculated using Equation (2).
Absorption Percentage = (
𝑤2−𝑤1
𝑤1
) x 100 eq. (2)
where:
W1 = weight of the specimen after complete drying (kg)
W2 = weight of surface dry sample after immersion in
water (kg)

11. Absorption (%) Absorption
Rating
Concrete Quality
<3.0 Low Good
3.0 t0 5.0 Average Average
>5.0 High Poor
Table 1. Assessment Criteria for Absorption
Source: CEB, 1989

12. TREATMENT
The treatments were as follows:
Treatment (T1): 0 MD + 100% cement + 100% sand
Treatment (T2): 5% MD + 95% cement + 100% sand
Treatment (T3): 10% MD + 90% cement + 100% sand
Treatment (T4): 15% MD + 85% cement + 100% sand
Treatment (T5): 20% MD +80% cement +100% sand

13. STATISTICAL DESIGN
 Data gathered were statistically analyzed in Completely
Randomized Design (CRD) with three (3) trials or
replications.
 Analysis of variance (ANOVA) was used to test the
significance of the different treatment means.
 If found significant in the ANOVA, Duncan Multiple Range
Test (DMRT) at 1% and 5% levels of significance was
used to compare and determine which among the
treatment means were significantly different from each
other.

14. RESULTS AND DISCUSSION
Trial
Initial Wt.,
kg
Recovered MD,
kg Recovery %
1
2
3
109.25
87
92.5
16.25
13
18.5
14
14.94
20
Mean 96. 25 15.92 16.31
Percentage Recovery
Table 2 shows the amount of marble dust recovered by using the
process of colloidal suspension. It can be seen that 96.25 kg of
marble dust yielded only 15.92 kg or equivalent to 16.31%
recovery. The recovered marble dust has particle size of 75
microns.
Table 2. Percentage Recovery of Marble Dust

15. 0
100
200
300
400
500
600
0 1 2 3 4 5 6
Compressive
Strength
(KPa)
Treatment
14 days
28 days
Figure 2. Relationship of compressive strength to curing period
RESULTS AND DISCUSSION

16. Treatment
Compressive
Strength, KPa
(14 days)
Compressive
Strength, KPa
(28 days)
T1
T2
T3
T4
T5
453
513
523
500
500
290
500
530
480
490
Significance ns ns
Table 3. Compressive Strength of CHB at 14 and 28 days of curing
Standard compressive strength: 5,810 KPa (Fajardo, ___)
RESULTS AND DISCUSSION

17. RESULTS AND DISCUSSION
Table 4. Density, water absorption and absorption percentage
after 28 days of curing
Treatment Density
g/cm3
Water
Absorbed, g
Absorption
Percentage, %
T1
T2
T3
T4
T5
1.59
1.65
1.63
1.66
1.70
70b
150a
20b
40b
80ab
0.80
1.65
0.22
0.45
0.86
Significance - ** -
In a column, means marked with the same letter are not significantly different at 1% level (DMRT)

18. 0
200
400
600
800
1000
1200
T1 T2 T3 T4 T5 Commercial
CHB
Compressive
Strength,
KPa
Treatment
14 days
28 days
450
290
510
500
520
530
500
480
500
490
967
950
Figure 3. Comparison of CHB with marble dust to commercial
CHB in terms of compressive strength
RESULTS AND DISCUSSION

19. 0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
T1 T2 T3 T4 T5 Commercial
CHB
water
Absorption,
%
Treatment
water absorption
0.8
1.65
0.45
0.86
4.05
0.22
Figure 4. Comparison of CHB with marble dust to commercial CHB
in terms of water absorption
RESULTS AND DISCUSSION

20. Table 5: Simple cost and return analysis of Concrete Hollow
Blocks with 10 % marble dust as cement replacement
Particular Value
I Annual Fixed Cost (AFC)
1. Investment Cost
2. Life Span
3. Salvage Value (10% IC)
4. Depreciation (Straight Line)
5. Repair and Maintenance (2%IC)
AFC
Php300.00
5 years
Php30
Php54
Php6
Php60.00/yr
II Annual Variable Cost (AVC)
1. Labor
2. Water
3. Hauling Cost
4. Raw Materials
Cement (648 bags)*
Sand (5040 ft3)*
AVC
Php115 200.00
Php6000.00
Php6840.00
Php162,000.00
Php142,826.57
Php432,866.57/yr
III Capacity 46,080 CHB/yr
IV Production Cost Php9.40/CHB
V Selling price (30% mark-up price) Php12.22/CHB
VI Gross Income (GI) Php563,097.60/yr
VII Net Income [GI-(AFC+AVC )] Php130,171.03/yr
*Market price, Odiongan, Romblon (2017)

21. CONCLUSION
 In terms of compressive strength and water absorption,
CHB with 10% marble dust as cement replacement was
found to be optimum
 All CHBs with marble dust replacement passed the
assessment criteria for water absorption.
 The calculated break-even cost or cost of producing
one CHB was Php9.40.
 Selling price of one CHB with 10% marble dust was
estimated to be Php12.22 (at 30% mark-up) as
compared to the current price of commercial CHB in
the locality which is 14.00.
 Hence, by using the CHB with 10% marble dust, a
saving of Php1.78/CHB or a total income of
Php130,171.03/year can be realized.

22. RECOMMENDATION
Use CHB molding machine in the
preparation of hollow blocks for
better comparison.
Use mixer to attain uniformly in
the preparation of aggregates
Follow-up research on the
different type of cement to be
used is recommended.

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