Asphalt Test

ASPHALT TECHNOLOGY

IMPORTANCE OF ASPHALT

ASPHALT A dark brown to black cementitious material, solid to semi-solid in consistency in which the predominating constituents are called bitumen, which are found in nature, or as residue in petroleum refining.

Properties of Asphalt •  Physical a. Consistency – ranges from a very thin liquid to a stiff semisolid state.

b. Temperature Susceptibility – thermoplastic substance. c. Adhesion – ability to stick to the agg. d. Cohesion – ability to hold the agg. particle firmly e. Durability– resistance of asphalt to changes in properties due to weathering or aging.

f. Hardening – asphalt hardens when heated to higher temperature.

Chemical Composition of Asphalt 1. Asphaltenes a. Gives Color

Black

b. Hardness 2. Maltenes a. Resin – provides stickiness (adhesiveness) b. Oil – influences viscosity of asphalt & imparts softness

Uses of Asphalt 1.

Binder

2.

Water proofing material

3.

Joint and crack filler

4.

Roofing

5.

Prime Coat

6.

Tack Coat

7.

Sealing (PCCP)

8.

Pipe Coating

Kinds of Asphalt 1. Natural Asphalt a. Rock Asphalt b. Lake Asphalt or Pure Deposit 2. Manufactured Asphalt a. Asphalt Cement – Penetration grade 40 to 300 b. Blown Asphalt – Penetration grade 0 to 30 c. Liquid Asphalt – Cutback asphalt & emulsified asphalt

Refining Process of Petroleum Asphalt Asphalt is a natural component of petroleum crude oil taken from the hundred of thousand of oil wells throughout the world today

CLASSIFICATION OF PAVING ASPHALT A.  Asphalt Cement or Hot Asphalt, 99% (bitumen) pure, 1% impurities Characteristics 1. Solid to semi-solid in consistency 2. Odorless 3. Black in Color - Penetration Grades: 40-50, 60-70, 85-100, 120-150, 200-300

CLASSIFICATION OF PAVING ASPHALT B. Liquid Asphalt Cutback Asphalt – blend of Asphalt Cement + Solvent Classification: 1. Slow Curing (SC) – Asphalt Cement + Non-volatile or slowly volatile roads oils - liquid at room temperature - SC – 70 - SC – 250 - SC – 800 - SC – 3000

CLASSIFICATION OF PAVING ASPHALT B. Liquid Asphalt Cutback Asphalt – blend of Asphalt Cement + Solvent Classification: 2. Medium Curing (MC) – Asphalt Cement + Kerosene - characteristic smell of kerosene - liquid at room temperature - MC – 30 - MC – 70 - MC – 250 - MC – 800 - MC – 3000

CLASSIFICATION OF PAVING ASPHALT B. Liquid Asphalt Cutback Asphalt – blend of Asphalt Cement + Solvent Classification: 3. Rapid Curing (RC) – Asphalt Cement + Gasoline - characteristic smell of gasoline - liquid at room temperature - RC – 70 - RC – 250 - RC – 800 - RC – 3000

CLASSIFICATION OF PAVING ASPHALT B. Liquid Asphalt Emulsified Asphalt – blend of Asphalt Cement + Water + Emulsifier - usually 60% asphalt and 40% water Characteristics: - liquid at room temperature - Pungent Odor - Chocolate brown in color

CLASSIFICATION OF PAVING ASPHALT Emulsified Asphalt á Anionic Emulsified Asphalt - Negatively Charged globules Classifications: - Rapid Setting (RS-1, RS-2) - Medium Setting (MS-1, MS-2) - Slow Setting (SS-1, SS-1h)

CLASSIFICATION OF PAVING ASPHALT Emulsified Asphalt á Cationic Emulsified Asphalt - Positively Charged globules Classifications: - Rapid Setting (CRS-1, CRS-2) - Medium Setting (CMS-1, CMS-2) - Slow Setting (CSS-1, CSS-1h)

á Asphalt/Concrete Joint Sealer/Filler - Hot poured elastic type - Preformed/Pre-molded

Asphalt Cement QUALITY/PHYSICAL TESTS:

1. Specific Gravity 2. Penetration 3. Loss on Heating 4. Penetration after Loss 5. Spot test 6. Flash Point 7. Ductility 8. Solubility

Emulsified Asphalt QUALITY/PHYSICAL TESTS: 1. Viscosity 2. Distillation 3. Cement Mixing 4. Sieve Test 5. Storage Stability 6. Test on Residue a.

Penetration

b.

Ductility

c.

Stability

Cutback Asphalt QUALITY/PHYSICAL TESTS:

1. Viscosity 2. Flash Point 3. Distillation 4. Test on Residue a. Penetration b. Ductility c. Solubility d. Spot test

QUALITY/PHYSICAL TEST OF ASPHALT CEMENT 1. SPECIFIC GRAVITY – indicates the uniformity of the product/supply APPARATUS: Fisher pycnometer, heating device, balance

a. Weigh pycnometer empty

QUALITY/PHYSICAL TEST OF ASPHALT CEMENT 1. SPECIFIC GRAVITY – indicates the uniformity of the product/supply

Fill the pycnometer with water


b. Then weigh the pycnometer


Pour the heated asphalt sample into the pycnometer to about three fourths of its capacity.


c. Cool the pycnometer and sample, then weigh with the cover.


Fill the pycnometer with sample plus water


d. Then weigh Formula: Specific Gravity = (c - a) ÷ [(b - a) - (d - c)]

QUALITY/PHYSICAL TEST OF ASPHALT CEMENT 2. PENETRATION – determines the hardness of asphalt Apparatus: Penetrometer, timer, mc can, water bath, thermometer

a. Pour heated sample in MC can then cool

QUALITY/PHYSICAL TEST OF ASPHALT CEMENT 2. PENETRATION – determines the hardness of asphalt

b. Immerse in a water bath for 1-1/2 to 2 hours at a temperature of 250C

QUALITY/PHYSICAL TEST OF ASPHALT CEMENT 2. PENETRATION – determines the hardness of asphalt

c. Immediately after the curing period, perform the test. Take at least three (3) penetration trials/readings, report the penetration as the average of the three

QUALITY/PHYSICAL TEST OF ASPHALT CEMENT 3. LOSS ON HEATING – determines the rate of loss of volatile oil on asphalt when heated and the change in penetration caused by excessive heating Apparatus: Oven with revolving shelf, mc cans, balance

a. Weigh MC cans empty (take at least two trials)

QUALITY/PHYSICAL TEST OF ASPHALT CEMENT 3. LOSS ON HEATING – determines the rate of loss of volatile oil on asphalt when heated and the change in penetration caused by excessive heating

b. Pour 50 grams each of the heated sample in the two MC cans.


c. Cool and weigh

QUALITY/PHYSICAL TEST OF ASPHALT CEMENT 3. LOSS ON HEATING – determines the weigh of loss of volatile oil on asphalt when heated and the change in penetration caused by excessive heating

d. Place the samples in the rotating shelf of the oven maintained at a temperature of 1630C for five (5) hours


d. Cool and weigh

Computation/Formula: % loss = weight loss after heating x 100 mass of original sample

QUALITY/PHYSICAL TEST OF ASPHALT CEMENT 4. SPOT TEST – determines if asphalt is over heated during production Apparatus: Florence flask, filter paper, pipette or buret, balance, 25% xylene-heptane solution

a. Weigh 2 grams of the heated sample in a florence flask

QUALITY/PHYSICAL TEST OF ASPHALT CEMENT 4. SPOT TEST – determines if asphalt is over heated during production

b. Pour 10 ml of the solvent (25 % xylene – heptane solution) in the florence flask


c.

Swirl the flask to dissolve the sample with the aid of a boiling water bath. The process is repeated until complete dispersion has taken place. Cool the asphalt solvent mixture to room temperature for 30 min. then warm again for 15 min in a water bath at 320C


c.

A drop of warm mixture shall be placed on the filter paper. Examine the drop after 5 min. if the drop forms a brown or yellowish brown circular stain, with a darker solid or annular nucleus in the center, the tests shall be reported as positive. But if the drop forms a uniformly brown circular stain, repeat placing the drop on another filter paper the following day. And if it forms the same uniformly brown circular stain, then report it as negative, but if the drop forms a solid or annular nucleus report it as positive.

QUALITY/PHYSICAL TEST OF ASPHALT CEMENT 5. FLASH POINT – indicates the safe heating temperature of asphalt Apparatus: Cleveland Open Cup, thermometer

a. Fill the cup with the heated sample

QUALITY/PHYSICAL TEST OF ASPHALT CEMENT 5. FLASH POINT – indicates the safe heating temperature of asphalt

b. Place the cup in the heater. Apply heat until the temperature of the sample reaches at least 280C below the flash point

QUALITY/PHYSICAL TEST OF ASPHALT CEMENT 5. FLASH POINT – indicates the safe heating temperature of asphalt

Test flame

c. Pass the test flame across the center of the cup. Record as the observed flash point the temp. when a flash appears at any point on the surface of the sample.

QUALITY/PHYSICAL TEST OF ASPHALT CEMENT 6. DUCTILITY – measures the ability of the asphalt to stretch without breaking

Equipment/Apparatus: 1. Ductility machine


2. Ductility molds/base plate (brass plate)


Procedure: a. Pour the heated sample into the prepared mold until it is level full


b. Cool the sample and the mold for at least 30 mins. and then place the mold in the water bath maintained at a temperature of 250C for 85 to 95 mins.


c. Remove the briquette from the plate, detach the side pieces and attach the clips to the pins/hooks of the testing machine with a bath of the machine maintained at 250C. Pull the clips apart at a rate of 5 cm/min. Measure and record the distance through which the clips have been pulled to produce rupture

JOB MIX FORMULA The job-mix formula is the primary quality control mechanism for the production of asphalt mixture, mixture, which shall conform with following ranges of tolerance:

Passing No. 4 and larger sieves Passing No. 8 to No. 100 sieves Passing No. 200 sieves Bituminous material Temperature of mixture

+/-7% +/-4% +/-2% +/-0.4% +/-10°C

a. mixture shall have a minimum dry comprehensive strength of 1.4Mpa (200psi) b. The mixture shall have a mass percent air voids with the range of 3 to 5. c. The mixture shall have an index of retained strength of nor less than 70%

The Marshall Stability Method is the most commonly used method in the design and evaluation of bituminous concrete mixes.

QUALITY CONTROL TEST FOR ASPHALT MIX A. The immersion/Compression test determines the index of Retained Strength of the mix. Which is the ratio of wet to dry stability of the mix (compressive strength).

QUALITY CONTROL TEST FOR ASPHALT MIX B.  Extraction and Grading tests determines asphalt content and practice size distribution of coarse and fine aggregates, respectively. C.  The laboratory density test determines the degree of compaction.

Gradation Ranges – Hot Plant Mix Bituminous Pavements (Mass percent passing square sieves, AASHTO T 11 and T 27) Sieve Designation, mm

A

B

C

D

E

F

G

37.5 (1 ½ inch.)

100

-

-

-

-

-

-

25 (1 inch.)

95-100

100

100

-

-

-

-

19 (3/4 inch)

75-95

95-100

95-100

100

-

100

-

12.5 (1/2 inch.)

68-86

68-86

95-100

100

-

100

9.5 (3/8 inch.)

54-75

56-78

56-78

74-92

95-100

-

95-100

4.75 (No.4)

36-58

36-60

36-60

48-70

75-90

45-85

30-50

2.36 (No. 8)

25-45

27-47

27-47

33-53

62-82

33-53

5-15

1.18 (No. 16)

-

18-37

18-37

22-40

38-58

-

-

0.600 (No. 30)

11-28

11-28

13-28

15-30

22-42

-

-

0.300 (No. 50)

-

6-20

9-20

10-20

11-28

10-20

-

0.075 (No. 200)

0-8

0-8

4-8

4-9

2-10

3-8

2-5

ITEM 310 – BITUMINOUS CONCRETE SUREFACE COURSE 1995 STANDARD SPECIFICATION, GRADING E JOB-MIXING FORMULA ITEM 310-B I.  Gradation Sieve Sizes Inch mm

Job Mix Gradation

Job Mix Specifications Min. Max.

General Specifications Min. Max.

1

25.4

100

100

100

100

100

¾

19

99

95

100

95

100

½

12.5

81

74

86

68

86

3/8

9.5

68

61

75

56

78

#4

4.75

50

43

57

38

60

#8

2.36

38

34

42

27

47

#16

1.18

28

24

32

18

37

#30

0.600

18

14

22

11

28

#50

0.300

11

7

15

6

20

#200

0.075

5

3

7

0

8

ITEM 310 – BITUMINOUS CONCRETE SUREFACE COURSE 1995 STANDARD SPECIFICATION, GRADING E JOB-MIXING FORMULA

II. Asphalt Content a. Asphalt Cement b. % be Weight of Aggregates c. % Weight of Mix

Penetration 60/70 5.52 5.23

III. Filler Fly Ash IV.  Additives Hydrated Lime V. Temperature Asphalt Cement Aggregates Mixing Compaction

135oC 150oC 145oC

140oC 160oC 175oC 107oC minimum


B. BLENDING COMPOSITION OF AGGREGATES Bin No. 1 -- Sand Bin No. 2 -- 3/8” Agg. Filler Bin -- Cement

-

83.5% 16.0% 0.5%


C. GRADATION OF AGGREGATES Sieve Designation

Result

General Specification

Job-Mix Specification

(12.5)

100

100

100

3/8”

(9.5)

89

95-100

95-100

No.4

(4.75)

82

75-90

75-89

No.8

(2.36)

64

62-82

62-68

No.16

(1.18)

40

38-58

38-44

No.30

(0.60)

26

22-42

22-30

No.50

(0.30)

15

11-28

11-19

No.200

(0.075)

5

2-10

3-7

(inch)

(mm)

½”


D. SPECIFIC GRAVITY Specific Gravity of Asphalt Cement = Effective Sp. Gr. of Aggregates =

1.03 2.79


E. TEST ITEM Specifications

Items

Result

1.  Optimum Asphalt Content (%) by. wt. of mix 2. Stability (lbf) 3. Number of blows each face 4. Flow (0.01 in.) 5. Air Voids 6. Compacted Pavement Density (%) 7. Mixing Temperature, °C 8. Compaction Temperature, °C 9. Laying Temperature, °C

5.50 2700 75 13 3.75 90 150 130 130

Min. 5.10

Max. 5.90

1800

+

8 3 90 130 120 120

16 3 + 165

MARSHALL TEST Procedure: 1. Segregate the aggregates in different size according to their grading. 2. Batch wt. 3. Heating of aggregates. A. Heating temperature of Aggregates - 177°C-191°C B. Heating temperature of Asphalt 121°C-138°C 4. Mix – mixing temperature 5. Mold the specimens

-

163°C Compaction Temp. 124°C

Mold it by compaction 25 times with a heated Spatula fifteen times around & remaining with at random over the mixture. The remaining half of the mixture similar spading action repeated. No. of blows depends on traffic you are designing.

MARSHALL TEST 6. The cool the specimen – extrude the mold after 24 hours. 7. Measure the specimen at four (4) angles and get the average. 8. Get Gmb (Bulk Specific Gravity) 9. Water Cure – 30-40 minutes at a temperature of 60°C. 10. Take the stability test by means of Marshall apparatus and flow test.

Table 5.2 MARSHALL MIX DESIGN CRITERIA Light Traffic Surface and Base

Marshall Method Mix Criteria 1

Min

Compaction, number of blows each end of specimen

Max

Medium Traffic Surface & Base Min

35

Max

Heavy Traffic Surface & Base Min

50

Max 75

Stability, N (lb.)

3336 (750)

-

5338 (1200)

-

8006 (1800)

-

Flow, 0.25 mm (0.01 in.)

8

18

8

16

8

14

Percent Air Voids

3

5

3

5

3

5

65

75

Percent Voids in Mineral Aggregate (VMA) Percent Voids Filled With Asphalt (VFA)

See Table 5.3

70

80

65

78

Common Distresses for Asphalt Concrete Pavements

QUALITY/PHYSICAL TEST OF CUTBACK ASPHALT 1. SPECIFIC GRAVITY Apparatus: same as in asphalt cement

a.  Weigh the pycnometer empty. b.  Weigh the pycnometer with water c.  Weigh the pycnometer filled with sample c - a Specific Gravity = ----------------b - a

QUALITY/PHYSICAL TEST OF CUTBACK ASPHALT 1. KINEMATIC VISCOSITY – measures the resistance of the asphalt to flow Equipment/Apparatus: Viscometer, water bath, thermometer,

a.

Mount the viscometer in the bath maintained at 600C

b. Mix the sample thoroughly and measure a 20 ml representative sample

QUALITY/PHYSICAL TEST OF CUTBACK ASPHALT 1. KINEMATIC VISCOSITY – measures the resistance of the asphalt to flow

c. Introduce sample through the big tube into the cross arm until the leading edge stands within 0.5ml of the fill mark


d. Allow the charged viscometer to remain in the bath for around ten(10) minutes to attain temperature equilibrium.


e. Start the flow of asphalt in the viscometer by applying pressure to the big tube or slight vacuum to the small tube, until gravity flow is initiated.


f. Record the time required for the leading edge of the meniscus to pass from the first timing mark to the second. Viscosity @ 600C, Cst = time in seconds x Calibration Constant of viscometer, Centistokes / Second

QUALITY/PHYSICAL TEST OF CUTBACK ASPHALT 2. DISTILLATION – determines the asphalt content of liquid asphalt Equipment/Apparatus: Distilling flask, condenser, adapter, shield, shield and flask support, heat source (bunsen burner), graduated cylinder, thermometer, balance

a. Weigh in a 500 ml flask the mass of a 200 ml of the sample calculated based from the specific gravity of the material

QUALITY/PHYSICAL TEST OF CUTBACK ASPHALT 2. DISTILLATION – determines the asphalt content of liquid asphalt

b. Place the flask in the shield supported by wire gauze in a ring/tripod

c. Assemble the distillation apparatus


d.

Pass cold water through the condenser jacket. Apply heat to the distilling flask

e. Record the volume of distillate starting from 225°C, 260° C , 3150C


f.

When the temperature reaches 3600C, extinguish the flame & remove the flask and thermometer. Immediately pour the contents of the flask in the residue container

g. Record the total volume of distillate collected at 3600C

Residue, % by volume vol.of orig sample-total vol.of distillatex100 vol of original sample TEST ON RESIDUE: 1.  Penetration 2.  Ductility 3.  Solubility 4.  Spot

QUALITY/PHYSICAL TEST OF CUTBACK ASPHALT 3. FLASH POINT – same significance as in asphalt cement The procedure is similar to asphalt cement, the difference is just in the method of heating the sample, since the flash point of cutback is lower than asphalt cement: heating of sample is through a water bath, not direct heating. Apparatus: Tag open cup, thermometer

a.

Pour sample into the glass container

b. Place the glass container in the water bath and attached the thermometer to the heater

QUALITY/PHYSICAL TEST OF CUTBACK ASPHALT 3. FLASH POINT

c. Start heating the water bath with the glass container filled with sample. Pass a test flame across the center of the cup. Record as the observed flash point the temperature reading on the thermometer when a flash appears at any point on the surface of the sample.

QUALITY/PHYSICAL TEST OF EMULSIFIED ASPHALT 1. VISCOSITY SAYBOLT Equipment/Apparatus: Saybolt Viscometer and bath, 60 cc receiving flask, #100 sieve, thermometer

b. a.

Stir the sample thoroughly and pour into a 100 ml. flask. Place the flask in the water bath at 250C for 30 mins.

Place the cork stopper in position and pour the sample into the viscometer through the No. 20 sieve

QUALITY/PHYSICAL TEST OF EMULSIFIED ASPHALT 1. VISCOSITY, SAYBOLT

c.

Place a 60 cc receiving flask under the outlet tube. Snap the cork at the same time starting the timer

d. Stop the timer the moment the lower meniscus on the flask reaches the 60 cc mark. Record the effluent time in second.

QUALITY/PHYSICAL TEST OF EMULSIFIED ASPHALT 2. SIEVE TEST – determines the presence of larger globules of asphalt in the emulsion Equipment/Apparatus: Sieve #20, pan, sodium oleate solution/distilled water, balance

a.

Record the mass of the sieve + pan

b. Weigh 1000 gms of the emulsified asphalt into a suitable container

QUALITY/PHYSICAL TEST OF EMULSIFIED ASPHALT 2. SIEVE TEST – determines the presence of larger globules of asphalt in the emulsion

c.

Pour the sample through sieve No. 20.

d. Wash the container and residue until the washwater is clear

QUALITY/PHYSICAL TEST OF EMULSIFIED ASPHALT 2. SIEVE TEST – determines the presence of larger globules of asphalt in the emulsion

e. Place the pan under the sieve and f. Cool and weigh oven dry for two hours at 1100C Weight Residue Sample Retained,% = ----------------------------X 100 1000

QUALITY/PHYSICAL TEST OF EMULSIFIED ASPHALT 3. CEMENT MIXING – determines the resistance of the emulsion to breakdown on the job. It indicates the rate at which the emulsion will break when mixed with aggregates

Apparatus/Materials: Sieves(#80 &14), dish(watch glass), stirring rod, graduated cylinder, balance, cement, oven

a. Dilute the emulsion with distilled water to a residue of 55%, as determined by the distillation test Example: % residue = 58 55 ÷ 58 x 100 = 95 ml of sample For 100 ml solution: 100 - 95 = 5 ml of water for dilution


c. Sieve 50 grams of portland cement through No. 80 sieve

d. Measure a 100 ml solution with the computed proportion


e. Add the diluted solution to the 50 grams cement

f.

Stir the mixture at once with the steel rod using a circular motion at a rate of 60 rpm


g.

At the end of the one minute mixing period, add 150 ml of distilled water and continue the stirring for 3 mins.

h. Weigh the No. 14 sieve with a pan or watch glass


i.

Pour the mixture through a weighed No. 14 sieve. Use repeated washings to completely remove material from the mixing bowl

j. Pour the washings over the sieve


k.

Rinse the sieve using distilled w a t e r, h e l d a t a h e i g h t approximately 6 inches until the water is clear.

l.

Place the sieve in the weighed watch glass/shallow pan and oven dry at 1630C until constant weight

Amount of Residue Cement Mixing, % = -------------------------------- x 100 100

QUALITY/PHYSICAL TEST OF EMULSIFIED ASPHALT 4. STORAGE STABILITY – detect the tendency of the asphalt globules in the emulsion to settle during storage -- measures the permanence of the dispersion as related to time

Apparatus/Materials: two(2) 500 ml cylinders, glass pipet, balance, beakers(1000 ml cap), oven

a. Place a 500 ml sample to a glass cylinder

QUALITY/PHYSICAL TEST OF EMULSIFIED ASPHALT 4. STORAGE STABILITY – detect the tendency of the asphalt globules in the emulsion to settle during storage -- measures the permanence of the dispersion as related to time

b. Stopper the cylinder and allow to stand undisturbed at laboratory air temperature for 24 hours. c. Remove approximately 55 ml from the top of the emulsion by means of a pipet d. Weigh 50 gms into the previously weighed beaker with a 7 inches glass rod inside and a watch glass e. Take the total weight of the beaker f.

Siphon off the next 390 ml from the cylinder without any disturbance to the bottom sample

QUALITY/PHYSICAL TEST OF EMULSIFIED ASPHALT 4. STORAGE STABILITY – detect the tendency of the asphalt globules in the emulsion to settle during storage

g.

Mix the emulsion remaining in the cylinder and weigh 50 grams into the previously weighed beaker with glass rod and watch glass

h. Take the total weight of the beaker i. Heat the two beakers containing the top and bottom sample in a stove for an hour to remove water and then transfer in an oven at a temperature of 1630C for an hour. Cool and weigh j. The numerical difference in the asphalt contents of the top and bottom samples represents the storage stability of the emulsion

QUALITY/PHYSICAL TEST OF EMULSIFIED ASPHALT 5. DETERMINATION OF RESIDUE BY EVAPORATION – determines the asphalt content of liquid asphalt

Apparatus: Iron still, heat source, thermometer

a. Weigh iron still empty. Pour 200 grams sample in the iron still


b. Heat the iron still with sample until all water has evaporated, increase the temperature to 260 °C for 15 minutes. Extinguish the flame and weigh the iron still with residue


c. Immediately pour the contents of the iron still into a residue container d. Calculate the percent residue Formula: Weight Residue %, Residue = ------------------------------------ x 100 200

TESTS ON RESIDUE: 1.  Penetration 2.  Ductility 3.  Solubility Note: Same test procedures as in asphalt cement

BITUMINOUS MIXTURES Bituminous Mixture - is a combination of aggregate that are uniformly mixed and coated with bituminous/asphalt materials such as asphalt cement, cutback asphalt or emulsified asphalt Kinds of Bituminous Mixture - Bituminous/Asphalt Hot Mix - Bituminous/Asphalt Cold Mix

BITUMINOUS MIXTURES Composition of Bituminous Mixture - Bituminous Mix or Hot Mix Aggregate

+ Asphalt Cement

92% – 95%

5% - 8%

- Bituminous Cold Mix Aggregate + Cutback Asphalt 4.5% - 7% Aggregate + Emulsified Asphalt 6% - 10%

AGGREGATES Three kinds of aggregates for bituminous mix:

a. Coarse Aggregates – retained on No. 8 and larger sieve b. Fine Aggregates – passing # 8 and retained on # 200 c. Mineral Filler – passing # 200

Properties of Aggregates 1. Strength 2. Particle Shape 3. Surface Texture 4. Absorption and Specific Gravity 5. Gradation 6. Cleanliness 7. Affinity for asphalt

Properties of Bituminous Mixture 1.  Stability -- ability to resist deformation from imposed loads * ability to resist shoving and rutting under traffic Causes and Effects of Pavement Instability Causes

Effects

Excess asphalt in mix

Rutting and flushing or bleeding

Excess medium sand in mixture

Tenderness during rolling & for period after construction, difficulty in compacting

Rounded aggregate, little or no crushed surfaces

Rutting

Properties of Bituminous Mixture 2. Durability – ability to resist the detrimental effects of air, water, temperature and traffic

Causes and effects of lack of durability Causes

Effects

Low asphalt content High void content through design or lack of compaction Water susceptible (hydrophilic) aggregate in mixtures

Dryness or raveling Early hardening of asphalt followed by cracking or disintegration Asphalt film strips from aggregate leaving an abraded, raveled or mushy pavement

Properties of Bituminous Mixture 3. Flexibility – ability to bend slightly without cracking and to conform to gradual settlements and movements of the base and sub grade.

•  Factors affecting Flexibility - High asphalt content - Gradation (open graded)

Properties of Bituminous Mixture 4. Fatigue Resistance – ability to withstand repeated flexing caused by the passage of wheel loads Causes and effects of Poor Fatigue Resistance Causes Low asphalt content High design voids

Effects Fatigue cracking

Lack of compaction

Early aging of asphalt followed by fatigue cracking

Inadequate pavement thickness

Excessive bending followed by fatigue cracking

Early aging of asphalt followed by fatigue cracking

Properties of Bituminous Mixture 5. Skid Resistance – ability to offer resistance to slipping or skidding of the vehicle tires Causes and effects of Poor Skid Resistance Causes Excess asphalt

Effects Bleeding, low skid resistance Poorly textured or graded Smooth pavement, aggregate potential for hydroplaning Polishing aggregate in Low skid resistance mixture

Properties of Bituminous Mixture

6. Workability – ease with which paving mixture maybe placed and compacted Causes and effects of Workability Problems Causes

Effects

Large maximum-size particle

Rough surface, difficult to place

Excessive coarse aggregate

May be hard to compact

A mix temperature that is too low

Uncoated aggregate, not durable,rough surface hard to compact

Too much medium-size sand

Mix shoves under roller, remains tender

Low mineral filler content

Tender mix, high permeable

High mineral filler content

Mix may be dry or gummy hard to handle, not durable

Properties of Bituminous Mixture 7. Impermeability - prevents the passage of air and water into or through the asphalt pavement. Causes and effects of Permeability Causes

Effects

Low asphalt content

Thin asphalt films will cause early aging and raveling

High voids content in design mix

Water and air can easily enter pavement, causing oxidation and disintegration

Inadequate compaction

Will result in high voids in pavement, leading to water infiltration and low strength

QUALITY TESTS ON BITUMINOUS MIXES 1. EXTRACTION 2. GRADING/MECHANICAL ANALYSIS OF EXTRACTED AGGREGATES 3. BULK SPECIFIC GRAVITY 4. STABILITY TEST 1. Immersion – Compression test 2. Marshall Stability

QUALITY TESTS ON BITUMINOUS MIXES 1. EXTRACTION – determines the amount of asphalt present in the mix W1 - W2 % Extraction

= ------------------------- x 100

(% Asphalt, by wt. of mix)

W1

Where: W1 = weight of sample W2 = weight of sample after extraction

QUALITY TESTS ON BITUMINOUS MIXES 2. GRADING – determines the size distribution of aggregates whether it is in conformance with the approved design Sieve Size

Wt. Retained

Wt. Passing

¾” ½” 3/8” No. 4 No. 8 No. 16 No. 30 No. 50 No. 200 SPEC’S – refer to the approved job mix formula

% Passing

SPEC’S

QUALITY TESTS ON BITUMINOUS MIXES Example: Job-Mix Formula: READYCON Trading GRADING: Based on Grading E Item 310 =2004 DPWH SPEC’S Sieve Size

Cumulative, % Passing

½”

100

3/8”

98

No. 4

82

No. 8

64

No. 16

40

No. 30

26

No. 50

15

No. 200

5

Asphalt Content: % By Mass of Aggregates = 5.8

QUALITY TESTS ON BITUMINOUS MIXES Example: Evaluation of a Job-Mix Formula Sieve Size

%, Passing

Applying Tolerances

½”

100

-

100

3/8”

98

-

95 – 100

No. 4

83

-

75 – 90

No. 8

64

-

62 – 82

No. 16

40

-

38 – 58

No. 30

26

-

22 – 42

No. 50

15

-

11 – 28

No. 200 of Tolerances:5 Ranges Passing No. 4 and larger Sieves – ± 7% Passing No. 8 to No. 100 Sieves - ± 4% Passing No. 200 Sieve - ± 2% Bituminous Material - ± 0.4%

DPWH SPEC’S

2 - 10

Grading Spec’s to Adopt

QUALITY TESTS ON BITUMINOUS MIXES 3. BULK SPECIFIC GRAVITY - for unit weight determination - used in design computation - used in computation of the degree of compaction: Field Density/Specific Gravity % of compaction = -------------------------------------------- x 100 Laboratory Density/Specific Gravity Spec’s = 95%-97 %

QUALITY TESTS ON BITUMINOUS MIXES 4. STABILITY TEST 4.1 Immersion - Compression test (4 in dia. X 4 in ht) - measurement of the loss of cohesion or adhesion resulting from the action of water - Dry Stability - Wet Stability Wet Stability Index of retained strength, % = --------------------- x 100 Dry Stability Spec’s = 70% minimum

QUALITY TESTS ON BITUMINOUS MIXES 4. STABILITY TEST 4.2 Marshall Stability = (4 in dia. X 2-1/2 in ht) - intended for laboratory design and field control of asphalt paving mixtures Spec’s = refer to Marshall Design Criteria

TESTS ON BITUMINOUS MIXES

1. EXTRACTION

Apparatus/Material: Extraction machine, oven, pans,filter rings,graduated cylinder, solvent(gasoline)

a. Place the sample in a pan and heat/warm until it can be handled or mixed

a. Mix the sample thoroughly, quartering first before sampling

TESTS ON BITUMINOUS MIXES 1. EXTRACTION

c. Weigh an 850 grams sample

d. Place the sample in the bowl


e. Cover the sample with the solvent (gasoline)

f. Weigh the filter ring


g. Fit the filter ring around the edge of the bowl

h. Clamp the cover on the bowl tightly.


i. Place container under the drain to collect the solvent. Start the centrifuge revolving slowly and gradually increase the speed to a maximum of 3600 RPm until the solvent ceases to flow from the drains. Allow the machine to stop, add 200 ml (or more as appropriate for mass of sample) solvent and repeat the procedure at least three (3) times.


j. After the completion of the process transfer the aggregates from the bowl to the pan

k. Dry to constant mass together with the filter ring in an oven at 110 ± 50C. Cool and weigh


l. Cool the aggregates and the filter ring and weigh

TESTS ON BITUMINOUS MIXES 1. EXTRACTION Formula: W1 - (W2 + W3) Asphalt Content, % = ------------------------------- x 100 by mass of dry aggregates W2 + W3 where: W1 = mass of sample, grams W2 = mass of extracted aggregates, grams W3 = increase in mass of filter ring, grams

TESTS ON BITUMINOUS MIXES 2. GRADING/MECHANICAL ANALYSIS OF EXTRACTED AGGREGATES Apparatus/materials: set of sieves, pans,heating device,balance, disbursing agent

a. The test sample (aggregate from extraction test) after being dried & weighed shall be placed in a container & covered with water. Add a sufficient amount of wetting or disbursing agent such as calgon or soap which will promote the separation of fine material

b. The contents of the container shall be agitated vigorously

TESTS ON BITUMINOUS MIXES 2. GRADING/MECHANICAL ANALYSIS OF EXTRACTED AGGREGATES

c. The wash water shall be poured over a 0.075 mm wash sieve. The operation shall be repeated until the wash water is clear.

d.. The washed aggregates in the container shall be dried to constant mass at a temperature of 110 ± 50C and weighed

TESTS ON BITUMINOUS MIXES 2. GRADING/MECHANICAL ANALYSIS OF EXTRACTED AGGREGATES

e. The aggregate shall be sieved over sieves of the various sizes required by the specification covering the mixture, including the 0.075 mm sieve

f.. The weight of material passing each sieve and retained on the next and the amount passing the 0.075 sieve shall be recorded. Compute & report percent (%) passing on each sieve

TESTS ON BITUMINOUS MIXES 3. BULK SPECIFIC GRAVITY

Apparatus: specific gravity balance, App App

a. Weigh the specimen in air

b. Immerse the specimen in water bath at 250C for 3 to 5 minutes. Weigh.


c. Surface dry the specimen by blotting with a damp towel/cloth. Weigh


Formula: mass of the dry specimen in air, in grams Bulk Specific Gravity, Gmb = ----------------------------------------------------------mass of the saturated surface-dry specimen in air, in grams -

mass of the specimen in water, in grams

TESTS ON BITUMINOUS MIXES 3. IMMERSION COMPRESSION TEST Apparatus: Testing machine, balance, molds, supports, heating device, oven, water bath, spatula

a. Weigh around 2000 grams of the sample. The weighed sample shall be brought to the molding temperature which is 124 ± 100C

b. Approximately one-half of the heated mixture shall be placed in the molding cylinder & spaded virgously 25 times with 15 of the blows being delivered around the inside of the mold & the remaining 10 at random over the mixture

TESTS ON BITUMINOUS MIXES 3. IMMERSION COMPRESSION TEST

c. The sample shall be spaded vigorously 25 times with 15 of the blows being delivered around the inside of the mold & the remaining 10 at random over the mixture. The remaining half of the mixture shall be quickly transferred to to the molding cylinder & the same spading action

d. The mixture shall be compressed between the top & bottom plungers under an initial load of 150 psi to set the mixture against the sides of the mold.


e. The mixture shall be compressed between the top & bottom plungers under an initial load of 150 psi to set the mixture against the side of the mold. The support bars shall then be removed an the entire molding load of 3000 psi shall be applied for 120 second.

f. The specimen shall be remove from the mold with an ejection device. Make at least four specimen


g. After removal from the mold specimen shall be oven cured for 24 hours at 600C

h. Allow the specimen to cool to room temperature for at least two hours then determine the bulk specific gravity


i. 

Air dry the two specimens for at least four hours prior to the determination of the dry stability

j. Immerse the other two specimens in a water bath with a temperature of 500C for four days


k. Transfer the two specimens to another water bath with a temperature of 250C & store them there for two hours

l. Determine the wet stability

Formula: Wet Stability Index of retained strength, % = ----------------------------- x 100 Dry Stability

Asphalt/Concrete Joint Sealer/Filler 1. Hot Poured Elastic Type

TESTS

AASHTO M – 173 Specification

a. Safe heating temperature,°C

-

b. Pour Point,°C

242 max

c. Flow at 60 °C,mm

5.0 max

Penetration at 25°C, d. 150grams, 5 sec

90 max

Asphalt/Concrete Joint Sealer/Filler 2. Preformed: S PE C I F I CAT I O N S AASHTO M-33

AASHTO M-153

AASHTO M-213

689 – 5171 KPa

0.34 – 10.35 Mpa

689 – 5171 Kpa

Recovery

-

90% (min.)

70% (min.)

Density

-

-

304 Kg/m3 (min)

Compression

Water Absorption

Depends on thickness

AASHTO M-153

-

Preformed Sponge Rubber and Cork Expansion Joint fillers for Concrete Paving and Structural Construction

AASHTO M-213

-

Preformed Expansion Joint Fillers for Concrete Paving & Structural Construction (Non extruding and Resilient Bituminous Type)

AASHTO M-33

-

Preformed Expansion Joint filler for Concrete (Bituminous Type)

MINIMUM TESTING REQUIREMENTS One quality test for every . . . . . . . . . .

Kind of Materials

Quantity Represented

Minimum Quantity of Sample

Asphaltic Material

40 tonnes or 200 drums

4 liters/1 gallon

130 tonnes

20 kilograms

a. Hot Poured Elastic Type

Per shipment/Delivery

400 grams

b. Premolded/Preformed

Per shipment/Delivery

1 (400 mm x 400 mm)

I.

II. Asphalt Mix III. Asphalt/Concrete Joint Filler/Sealer

THANK YOU… GOD BLESS YOU !!!

Asphalt Test

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