38

=

CHAPTER III

RESULT AND DISCUSSION

This chapter presents the result and the discussion of the data collected. All data

are presented and analyzed based on objectives stated.

Physical Properties of Coarse Aggregate

The study determined the physical properties of coarse aggregate in terms of

specific gravity, absorption, unit weight, soundness, abrasion loss, moisture content,

wash loss on No. 200 and clay lumps.

Specific gravity. Aggregate specific gravity is used in a number of applications including

Superpave mix design, deleterious particle indentification and separation, and material

property change identification.

Coarse Aggregates (Mainit River)

1.) wt. in air saturated surface dry (SSD) 3052.0

2.) wt. in air oven dry sample (OD) 2994.0

3.) wt. of sample in water (H2O) 1674.0

A. Specific Gravity, (DRY) = 2

2994 = 2.173

1-3 1378

B. Specific Gravity, (SSD) = 1 3052

= 2.215 1-3 1378

C. Specific Gravity, (Apparent) = 2 2994

= 2.268 2-3 1320

D. Absorption, % = 1-2

x 100 58 X 100 = 1.937 2 2994

Coarse Aggregates (Kalambis river)

1.) wt. in air saturated surface dry (SSD) 2843.0

2.) wt. in air oven dry sample (OD) 2797.0 3.) wt. of sample in water (H2O) 1495.0

=

=

=

39

=

A. Specific Gravity, (DRY) =

2 2797

= 2.075

1-3 1348

B. Specific Gravity, (SSD) = 1

2843

= 2.109

1-3 1348

D. Specific Gravity, (Apparent) =

2 2797

= 2.148

2-3 1302

E. Absorption, % =

1-2 x 100

46 X 100 = 1.645

2 2797

Table 14 Test result on specific gravity of coase aggregates

Source of aggregate Specific gavity (DRY)

Specific gavity (SSD)

Specific gavity (Apparent)

Mainit river 2.173% 2.215% 2.268%

Kalambis river 2.075% 2.109% 2.148%

As shown in table 14, the values of specific gravity of coarse aggregate from Mainit

river is 2.173% (DRY), 2.215% (SSD) and 2.268% (Apparent). And the values of specific

gravity of coarse aggregate from Kalambis river is 2.075% (DRY), 2.109% (SSD) and

2.148% (Apparent). The typical value for specific gravity of natural coarse aggregate is

2.6%. There are no minimum or maximum specific gravity or absorption values in

Superpave mix design. Rather, specific gravity is an aggregate quality needed to make

required volume calculations.

Absorption:

Table 15 Test result on absorption of coarse aggregates

Source of aggregate Absorption

Mainit river 1.937%

Kalambis river 1.645%

As shown table 15, the values of absorption of coarse aggregate from Mainit river

is 1.937%. And the values of absorption of coarse aggregate from Kalambis river is

1.645%. Therefore, both of the sample of coarse aggregate is not highly absorptive (less

=

=

=

40

than 5% absorption) and does not require more asphalt binder making the resulting hot

mix asphalt less expensive. Absorption requirements are of concern only regarding

aggregates used in hot mix asphalt and portland cement concrete. The intent is to avoid

using highly porous, absorptive aggregates because extra water and cement or asphalt

is needed to make a good mix.

Unit weight.The unit weight of aggregate affects the density of concrete and dead load of

structure.

Unit Weight (Mainit River)

Loose

A. Trial no. 1 2 3

B. Wt. of Mold + Sample 5.091 4.962 5.042

C. Wt. of Mold 1.125 1.125 1.125

D. Vol. of Mold 0.00296 0.00296 0.00296

E. Wt. of Sample 3.966 3.837 3.917

Ave : 3.907

Unit wt.=

wt. of sample

vol. of mold

3.907 = 1320 kg/m3

0.00296

Rooded

A. Trial no. 1 2 3

B. Wt. of Mold + Sample 5.563 5.539 5.465

C. Wt. of Mold 1.125 1.125 1.125

D. Vol. of Mold 0.00296 0.00296 0.00296

E. Wt. of Sample 4.438 4.414 4.34

Ave : 4.397

Unit wt.=

wt. of sample

vol. of mold

4.397 = 1486 kg/m3

0.00296

41

Unit Weight (Kalambis river)

Loose

A. Trial no. 1 2 3

B. Wt. of Mold + Sample 4.912 4.923 4.916

C. Wt. of Mold 1.125 1.125 1.125

D. Vol. of Mold 0.00296 0.00296 0.00296

E. Wt. of Sample 3.787 3.798 3.791

Ave : 3.792

Unit wt.=

wt. of sample

vol. of mold

3.792 = 1281 kg/m3

0.00296

Rodded

A. Trial no. 1 2 3

B. Wt. of Mold + Sample 5.245 5.289 5.397

C. Wt. of Mold 1.125 1.125 1.125

D. Vol. of Mold 0.00296 0.00296 0.00296

E. Wt. of Sample 4.12 4.164 4.272

Ave : 4.185

Unit wt.=

wt. of sample

vol. of mold

4.185 = 1414 kg/m3

0.00296 Table 16 Test result on unit weight of coarse aggregate

Source of aggregate Unit weight (Loose) Unit weight (Rodded)

Mainit river 1320 kg/m3 1486 kg/m3

Kalambis river 1281 kg/m3 1414 kg/m3

As shown in table 16 the values of unit weight of coarse aggregate from Mainit

river is 1320 kg/m3 (loose) and 1486 kg/m3 (rodded). And the values of unit weight of

coarse aggregate from Kalambis river is 1281 kg/m3 (loose) and 1414 kg/m3 (rodded).

42

Determining the value for unit weight is necessary for use for many methods of selecting

proportions for concrete mixtures.

Soundness: The soundness determines the aggregates resistance to disintegration by

weathering.

Table 17 Soundness test of coarse aggregate(Mainit river)

Sieve Size

Original Grading

of Sample %

Weight of Test Fractions

Before Test, g

Weight of Test

Fractions After Test, g

Percentage Passing

Designated Sieve After

Test

Weighted Percentage Loss

SOUNDNESS TEST OF COARSE AGGREGATES

2½ in to 2 in

20 4783 4105 14.18 2.84 2 in to 1½in

1½ in to 1 in

45 1525 1467 3.80 1.71 1 in to ¾ in

¾ in to ½ in

13 1008 906 10.12 1.34 ½ in to 3/8

3/8 in to NO. 4 12 298 274 8.05 0.97

Totals 90 7614 6752 36.15 6.85

Table 18 Soundness Test of coarse aggregate (Kalambis river)

Sieve Size

Original Grading

of Sample %

Weight of Test Fractions

Before Test, g

Weight of Test

Fractions After Test, g

Percentage Passing

Designated Sieve After

Test

Weighted Percentage Loss

SOUNDNESS TEST OF COARSE AGGREGATES

2½ in to 2 in

20 4783 4101 14.26 2.85 2 in to 1½in

1½ in to 1 in

45 1525 1461 4.20 1.89 1 in to ¾ in

¾ in to ½ in

13 1008 901 10.62 1.41 ½ in to 3/8

3/8 in to NO. 4 12 298 270 9.40 1.13

Totals 90 7614 6733 38.47 7.27

43

Table 19 Test result on soundness of coarse aggregate

Source of aggregate Soundness Specification

Mainit river 6.85% 12.0%max

Kalambis river 7.27%

As shown in table 19, the value of soundness of coarse aggregate in Mainit river

is 6.85%. And the value of soundness of coarse aggregate in Kalambis river is 7.27%.

Therefore, both of the sample of coarse aggregate had complied to the standard

specification for soundness which is 12.0% max. The quality of soundness of aggregate

or its resistance to the forces of weathering is one of the most important considerations

in the selection of a material for highway construction.

Abrasion. Abrasion resistance of aggregate often use as general indicator of qualtiy. It is

used to indicate aggregate toughness and abrasion chararacteristics.

Abrasion Test (Mainit river)

A. Grading Used A

B. No. of Spheres 12

C. Grading of Samples

Passing Sieve

Size Retained Sieve

Size Weight ( Gms.)

1 1/2" 1" 1250

1" 3/4" 1250

3/4" 1/2' 1250

1/2" 3/8" 1250

Total Weight 5000

D. Dry Weight Retained on Sieve No. 10 (After washing) 3514

E. Dry Weight Passing Sieve No. 10 1234

Table 20 Grading of samples for abrasion test (Mainit river)

44

F. Abrasion Loss ( % ) 29.72

G. Specification ( % ) 40.0 Max

Abrasion Test (Kalambis river)

A. Grading Used A

B. No. of Spheres 12

C. Grading of Samples

Passing Sieve

Size Retained Sieve

Size Weight (Gms.)

1 1/2" 1" 1250

1" 3/4" 1250

3/4" 1/2' 1250

1/2" 3/8" 1250

Total Weight 5000

D. Dry Weight Retained on Sieve No. 10 (After washing) 3574

E. Dry Weight Passing Sieve No. 10 1234

F. Abrasion Loss ( % ) 28.52

G. Specification ( % ) 40.0 Max

Table 22 Test result on abrasion of coarse aggregate

Source of aggregate Abrasion loss Specification

Mainit river 29.72% 40.0% max.

Kalambis river 28.52%

As shown in table 22, the value of abrasion loss of coarse aggregate from Mainit

river is 29.72% and from Kalambis river is 28.52%.Therefore, both of the sample of coarse

aggregatre had complied to the standard specification for abrasion which is 40.0 % max.

Table 21 Grading of sample for abrasion test (Kalambis river)

45

The percentage is a measure of the degradation or loss of material as a result of impact

and abrasive actions.

Clay lumps:

Table 23 Clay lump test of coarse aggregate (Mainit river)

Size of Particles Mass of Mass of Mass of Clay Lumps

Making Up Test Test Test Test %

Sample Retained Sample, Sample, Sample, ( 1 -2 / 1 ) x 100

before after

mm ~ inches min, g soak,g wash,g

No. 4 to 3⁄8-in.) 1000 min 0.0 0 0

3⁄8 to 3⁄4-in.) 2000 min 0.0 0 0

(3⁄4 to 11⁄2-in 3000 min 3005.2 2999.2 0.200

over 11⁄2-in. 5000 min 0.0 0 0

%Average Clay Lumps = 0.200

Table 24 Clay lump test of coarse aggregate (Kalambis river)

Size of Particles Mass of Mass of Mass of Clay Lumps

Making Up Test Test Test Test %

Sample Retained Sample, Sample, Sample, ( 1 -2 / 1 ) x 100

before after

mm ~ inches min, g soak,g wash,g

No. 4 to 3⁄8-in.) 1000 min 0.0 0 0

3⁄8 to 3⁄4-in.) 2000 min 0.0 0 0

(3⁄4 to 11⁄2-in 3000 min 3002.5 2997.4 0.170

over 11⁄2-in. 5000 min 0.0 0 0

%Average Clay Lumps = 0.170

46

Table 25 Test result on clay lumps of coarse aggregate

Source of aggregate Clay lumps Specification

Mainit river 0.200% 1.0% max.

Kalambis river 0.170%

As shown in table 25, the clay lumps of coarse aggregate from Mainit river is 0.2

%. And the clay lumps of coarse aggregate from Kalambis river is 0.17%. Therefore both

of the sample of coarse aggregate had complied to the standard specification for clay

lumps which is 1.0 % max. Clay lumps are materials that are easily crumbled or mashed

with the fingers. So an aggregate for concrete should not have a clay lumps more than

0.1%. The aggregate from Mainit river complies the requirement for clay lumps, therefore

it is safe to use for concrete.

Moisture Content:

Table 26 Sieve analysis of coarse aggregate (Mainit river)

Sieve Size Wt. Retained % Retained % Passing Specification

(inc.) (gms)

3" 0.0 0.0 100 100

2 1/2" 0.0 0.0 100 90 - 100

2" 0.0 0.0 100 -

1 1/2" 1368.0 45.8 54 25 - 60

1" 1522.0 51.0 3 -

3/4" 0.0 0.0 3 0 - 10

1/2" 0.0 0.0 3 0 - 5

3/8" 0.0 0.0 3 -

#4 0.0 0.0 3 -

#8 0.0 0.0 3 -

#16 0.0 0.0 3 -

#200 0.0 0.0 3 -

Pan - - - -

Total : 2890.0 Over Dry:

2,984.00 Original Wt. : 3,199.00

Mass of original sample: 3199 g.

47

Mass of dried sample: 2984 g.

Dry mass of sample after washing: 2890 g.

Moisture Content = (𝑚𝑎𝑠𝑠 𝑜𝑓 𝑜𝑟𝑖𝑔𝑖𝑛𝑎𝑙 𝑠𝑎𝑚𝑝𝑙𝑒−𝑚𝑎𝑠𝑠 𝑜𝑓 𝑑𝑟𝑖𝑒𝑑 𝑠𝑎𝑚𝑝𝑙𝑒)

𝑚𝑎𝑠𝑠 𝑜𝑓 𝑑𝑟𝑖𝑒𝑑 𝑠𝑎𝑚𝑝𝑙𝑒 × 100

𝑀𝑜𝑖𝑠𝑡𝑢𝑟𝑒 𝐶𝑜𝑛𝑡𝑒𝑛𝑡 = (3199−2984)

2984 × 100 = 7.21 %

Table 27 Sieve analysis of coarse aggregate (Kalambis river) Sieve Size Wt. Retained

% Retained % Passing Specification (inc.) (gms)

3" 0.0 0.0 100 100

2 1/2" 0.0 0.0 100 90 - 100

2" 0.0 0.0 100 -

1 1/2" 958.0 30.7 69 25 - 60

1" 1923.0 61.6 8 -

3/4" 0.0 0.0 8 0 - 10

1/2" 4.9 0.2 7 0 - 5

3/8" 0.0 0.0 7 -

#4 0.0 0.0 7 -

#8 0.0 0.0 7 -

#16 0.1 0.0 7 -

#200 1.3 0.0 7 -

Pan - - - -

Total : 2887.3 Over Dry:

3,119.50 Original Wt. : 3,272.00

Mass of original sample: 3272 g.

Mass of dried sample: 3119.5 g.

Dry mass of sample after washing: 2887.3 g.

𝑀𝑜𝑖𝑠𝑡𝑢𝑟𝑒 𝐶𝑜𝑛𝑡𝑒𝑛𝑡 = (3272−3119.5)

3119.5 × 100 = 4.89 %

Table 28 Test result on moisture content of coarse aggregate

Source of aggregate Moisture content

Mainit river 7.21%

Kalambis river 4.89%

48

As shown in table 28, the moisture content of coarse aggregate form Mainit river

is 7.21% and from Kalambis river is 4.89%. Obviously this aggregate has big amount of

moisture content because its from a river. This data can be used to adjust the ratio of

concrete mixture, so that it can’t affect to the concrete structure.

Wash Loss on No. 200:

(Mainit river)

Wash Loss = (𝑚𝑎𝑠𝑠 𝑜𝑓 𝑑𝑟𝑖𝑒𝑑 𝑠𝑎𝑚𝑝𝑙𝑒−𝑑𝑟𝑦 𝑚𝑎𝑠𝑠 𝑜𝑓 𝑠𝑎𝑚𝑝𝑙𝑒 𝑎𝑓𝑡𝑒𝑟 𝑤𝑎𝑠ℎ𝑖𝑛𝑔)

𝑚𝑎𝑠𝑠 𝑜𝑓 𝑑𝑟𝑖𝑒𝑑 𝑠𝑎𝑚𝑝𝑙𝑒 × 100

Wash Loss = (2984 −2890)

2984∗ 100 = 3.15%

(Kalambis river)

Wash Loss = (3119.5 −2887.3)

3119.5∗ 100 = 7.44%

Table 29 Test result on wash loss on no.200 of coarse aggregate

Source of aggregate Wash loss on no. 200 Specification

Mainit river 3.15% 1.0% max.

Kalambis river 7.44%

As shown in table 29, the wash loss on no. 200 sieve of coarse aggregate from

Mainiti river is 3.15% and from Kalamibis is 7.44%. Therefore, the target had not been

achieved for both sample of coarse aggregate, where the standard specification for wash

loss on no. 200 is 1.0 max.

49

Mechanical properties of coarse aggregate:

The study determined the mechanical properties of coarse aggregates in terms of

sieve analysis.

Figure 2 Graph showing the size distribution of aggregate (Mainit river)

Figure 3 Graph showing the size distribution of aggregate (Kalambis river)

0

10

20

30

40

50

60

70

80

90

100

PE

RC

EN

T P

AS

SIN

G

SIEVE SIZE

PARTICLES SIZE DISTRIBUTION

0

10

20

30

40

50

60

70

80

90

100

PE

RC

EN

T P

AS

SIN

G

SIEVE SIZE

PARTICLES SIZE DISTRIBUTION

50

According to the result, the coarse aggregate from Mainit river passing 3 inch

sieve size is 100%, passing 21

2 inch sieve size is 100%, passing 2 inch sieve size is 100%,

passing 11

2 inch sieve size is 54%, passing 1 inch sieve size is 3%, passing ¾ inch sieve

size is 3%, passing ½ inch sieve size is 3%, passing 3/8 inch sieve size is 3%, passing

no.4 sieve is 3%, passing no.8 sieve is 3%, passing no.16 sieve is 3%, passing no. 200

sieve is 3%. And the coarse aggregate from Kalambis river passing 3 inch sieve size is

100%, passing 21

2 inch sieve size is 100%, passing 2 inch sieve size is 100%, passing 1

1

2

inch sieve size is 69%, passing 1 inch sieve size is 8%, passing ¾ inch sieve size is 8%,

passing ½ inch sieve size is 7%, passing 3/8 inch sieve size is 7%, passing no.4 sieve is

7%, passing no.8 sieve is 7%, passing no.16 sieve is 7%, passing no. 200 sieve is 7%..

Therefore, target grading for coarse aggregate of bothsample had been achieved, where

the range for 3” sieve size is 100%, for 2 ½ “ is 90-100%, for 1½” is 25-60%, for 3/4 “ is

0-10%, and for 1/2“ 0-5%. The aggregate in Mainit River and Kalambis river are coarse

aggregate. Aggregate size and gradation are the most important factors when selecting

aggregate. It is one of the most important characteristics regarding the utilization of

aggregates in concrete.

Comparison of mechanical and physical properties of coarse aggregates to

acceptable standards

The specification is use to define the quality of aggregate, the nominal maximum

size of the aggregate, and other specific grading requirements.

51

Abrasion. The standard specification for Abrasion is 40.0 max. The value of

abrasion of coarse aggregate from Mainit river is 29.72% and from Kalambis river is

28.52%. Therefore both samples of coarse aggregate complies to the specification.

Specific gravity. The value of Specific gravity of coarse aggregate from Mainit river

is 2.173%(OD), 2.215%(SSD), 2.268%(APP) and from Kalambis river is 2.075%(OD),

2.109%(SSD), 2.148%(APP). There are no standard specification for specific gravity, but

there is a typical value for specific gravity of natural coarse aggregate which is 2.6%.

Therefore the values of specific gravity of samples of coarse aggregate is acceptable

because its not that far and does not exceed from the typical value of specific gravity of

natural coarse aggregate.

Absorption. The value of absorption of coarse aggregate from Mainit river is

1.937% and from Kalambis river is 1.645%. Therefore the samples of aggregate is not

highly absorptive because its value of absorption is less than 5%. The absorption is

important in determining the net water-cement ratio in the concrete mix.

Unit weight. The value of unit weight of coarse aggregate from Mainit river is 1320

kg/m^3 (Loose) and 1496 kg/m^3 (Rodded) and from Kalambis river is 1281 kg/m^3

(Loose) and 1414 kg/m^3 (Rodded). The value of unit weight is necessary for use for

many methods of selecting proportions for concrete mixtures.

Soundness. The standard specification for Soundness is 12.0 max. The value of

soundness of coarse aggregate from Mainit river is 6.85% and from Kalambis river is

7.27%. Therefore both samples of coarse aggregate complies to the specification. The

52

durability of aggregates or their resistance to the forces of weathering is one of the most

important considerations in the selection of a material for highway construction.

Moisture Content. The value of moisture content of coarse aggregate from Mainit

river is 7.21% and from Kalambis river is 4.89%. Obviously, this aggregate has big amount

of moisture content because it's from a river. This data can be used to adjust the ratio of

concrete mixture, so that it can't affect to the concrete structure.

Wash loss on no.200. The standard specification for the wash loss on no. 200

sieve is 1.0 max. The value of wash loss on no. 200 sieve of coarse aggregate from Mainit

river is 3.15% and from Kalambis river is 7.44%. Therefore, both of the sample of coarse

aggregate had not complied to the specification.

Sieve Analysis. Coarse aggregate shall conform to the requirements prescribed in

table 29 for the size number specified.

53

Ta

ble

30

Gra

din

g r

eq

uir

em

en

t fo

r c

oars

e a

gg

reg

ate

54

According in table 14 (from ASTM c33), the aggregate is size numer 3. As a

general rule, the largest aggregate should be no greater in diameter than one-third the

depth of the slab, or one-fifth the smallest dimension of the form. Generally coarse

aggregate is blended with finer aggregates (such as sand) to fill in the spaces left between

the large pieces and to “lock” the larger pieces together. This reduces the amount of

cement paste required and decreases the amount of shrinkage that could occur.