Highway Engineering

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 0

LABORATORY MANUAL

ON

HIGHWAY ENGINEERING

PREPARED BY

M.L. RATHORE

LAB ENGINEER

DEPARTMENT OF CIVIL ENGINEERING

JAYPEE UNIVERSITY OF

ENGINEERING & TECHNOLOGY

A.B. ROAD RAGHOGARH-GUNA (M.P.)-473226 (INDIA)

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 1

DEPARTMENT OF CIVIL ENGINEERING, JUET

HIGHWAY ENGINEERING LABORATORY

(COURSE CODE - 14B17CE572)

CONTENTS

EXP. NO.

NAME OF EXPERIMENTS TO BE PERFORMED

PAGE NO

--

Report writing

2 – 3

1.

Los Angeles Abrasion Test

4 – 6

2.

Aggregate Impact Test

7 – 9

3.

Aggregate Crushing Value Test

10 – 12

4.

Flakiness and Elongation Index (Shape Test)

13 – 16

5.

Flash and fire point test of bitumen

17 – 19

6.

Ductility Test of bitumen

20 – 22

7.

Bitumen Penetration Test

23 – 25

8.

Softening Point Test of Bitumen

26 – 28

9.

Bitumen content test by centrifuge extractor

29 – 30

10.

Marshall Stability Test

31 – 38

11.

Benkelman Beam Test

39 – 43

ADDITIONAL / DEMONSTRATION TYPE EXPERIMENTS

12.

Viscosity of tar/bitumen

44 – 45

13.

Specific gravity of tar/bitumen

46 – 47

14.

Stripping value of road aggregate

48 – 49

15.

Soundness of road aggregates

50 – 52

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 2

INSTRUCTIONS FOR LABORATORY REPORT WRITING

A full report is an extensive account of experiment, such as may be required for external readers. It should be a stand alone document and so is likely to include a description of the apparatus and a summery of the experimental procedure.

A full report is not to exceed 1500 words (excluding Tables and Diagrams). It is to be organized under the following headings:

OBJECTIVE/OBJECTIVES

EXPERIMENTAL SETUP WITH DIAGRAM THEORY TO BE USED FOR EXPERIMENT EXPERIMENTAL METHOD

OBSERVATIONS/DATA COLLECTED SAMPLE CALCULATIONS

EXPERIMENTAL RESULTS

DISCUSSION/CONCLUSIONS (Including that of errors) ERROR ANALYSIS

COMMENTS

OBJECTIVES

It contains the aim of the experiment and how the author is going to achieve his aim. EXPERIMENTAL SETUP WITH DIAGRAM

Write every experimental setup and instruments you used with their dimensions. Draw a neat sketch of experimental setup.

EXPERIMENTAL METHOD

It should contain a brief description of experimental method, a neat sketch of experimental setup.

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 3 THEORY TO BE USED FOR EXPERIMENT

Write theory behind your experiment briefly. OBSERVATIONS/DATA COLLECTED

Write down all data collected by you and also attached the signed lab data sheet. SAMPLE CALCULATIONS

Give the sample calculations. EXPERIMENTAL RESULTS

Represent experimental results in tabulated form and diagrams. DISCUSSIONS/ CONCLUSIONS

Compare your results with available reported results from standard literature. Give the reason of departure of your results from reported results.

The conclusions contains a summary (what has been done and what are the main results) and in addition to that some future prospective.

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 4 Experiment No-1

LOS ANGELES ABRASION TEST

1. To determine the Los Angeles abrasion value of aggregates.

2. To find out the suitability of aggregates for its use in road construction. APPARATUS/EQUIPMENTS REQUIRED:

1. It consists of a hollow cylindrical machine closed at both ends having 70 cm internal

diameter and 50 cm long, mounted on supports so that it may rotate about its horizontal

axis.

2. Steel spherical balls 48 mm in diameter and weighing 390 grams to 445 grams. The weight and number of balls per charge of aggregate depends upon the grading of aggregate sample.

3. Sieves of size 80 mm to 4.75 mm and 1.70 mm 4. Balance of capacity 10 kg.

5. Drying Oven 6. Steel Tray

SET OF SIEVES LOS ANGELES ABRASION TESTING MACHINE THEORY:

The aggregate used in surface course of the highway pavements are subjected to wearing due to movement of traffic. When vehicles move on the road, the soil particles present between the pneumatic tyres and road surface cause abrasion of road aggregates. The steel reamed wheels of animal driven vehicles also cause considerable abrasion of the road surface. Therefore, the road

aggregates should be hard enough to resist abrasion. Resistance to abrasion of aggregate is

determined in laboratory by Los Angeles test machine. The principle of Los Angeles abrasion test is to produce abrasive action by use of standard steel balls which when mixed with aggregates and rotated in a drum for specific number of revolutions also causes impact on aggregates. The

percentage wear of the aggregates due to rubbing with steel balls is determined and is known as Los Angeles Abrasion Value.

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 5 PROCEDURE:

1. Aggregate sample weighing 5 kg (for Grade A, B, C & D) and 10 kg (for Grade E, F & G) is put in the machine along with the abrasive charge as per given in table.

2. The machine is rotated at a speed of 30 to 33 R.P.M. for the specified number of revolutions (500 for grade A, B, C, D and 1000 for E, F, G)

3. Now the sample is taken out of the machine and sieved through 1.7 mm I.S. Sieve and the weight of aggregate passing through 1.7 mm sieve is determined.

Grading No. of spheres No of Revolutions Weight of sample (g) Wt. of charges (g)

A 12 500 5000 5000±25 B 11 500 5000 4584±25 C 8 500 5000 3330±20 D 6 500 5000 2500±15 E 12 1000 10000 5000±25 F 12 1000 10000 5000±25 G 12 1000 10000 5000±25

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 6 OBSERVATIONS & CALCULATIONS:

Type of aggregate

1. Grading = 2. Number of spheres used = 3. Weight of charge = 4. Number of revolution =

S. No Description Sample 1 Sample 2

1. Let the original weight of aggregate = W1 g

2. Weight of aggregate retained on 1.7 mm IS sieve after the test = W2 g

3. Loss in weight due to wear & tear = W1- W2 g

4. Percentage wear =





Los Angeles Abrasion Value = ………% PRECAUTIONS:

1. The cover should be fixed tightly before rotating the machine

2. All material should be discharged from the cylinder after the conduct of test. INTERPRETATION OF RESULTS

Los Angeles abrasion test is commonly used to evaluate the hardness of the aggregates. The test has more acceptability because the resistance to abrasion and impact is determined simultaneously. Depending upon the numerical; value, the suitability of aggregates for different road constructions can be judged as per the Indian Road Congress specifications given below;

Sr. No Type of Pavement Layer Max Permissible Abrasion Value in %

1 WBM Sub Base & Base Course 40

2 WBM Surfacing course 40

3 Dense Graded Bituminous Macadam (DBM) 35

4 Semi Dense Bituminous Concrete 35

5 Bituminous Concrete 30

6 Cement Concrete Surface Course 30

DISCUSSION:

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 7 Experiment No-2

AGGREGATE IMPACT TEST

(i) To determine the impact value of the road aggregates.

(ii) To assess their suitability in road construction on the basis of impact value. APPARATUS/EQUIPMENTS REQUIRED:

1. Impact testing machine weighing 45 to 60 kg and having a metal base plate with a plane lower surface of not less than 30 cm in diameter.

2. A cylindrical steel cup of internal diameter 102 mm, depth 50 mm and minimum thickness 6.3 mm.

3. A metal hammer or tup weighing 13.5 to 14 kg the lower end is cylindrical in shape, is 50 mm long, 100.0 mm in diameter, with a 2 mm chamber at the lower edge and case hardened. The hammer should slide freely between vertical guides and be concentric with the cup. The free fall of the hammer should be within 380±5 mm.

4. A cylindrical metal measure having internal diameter 75 mm and depth 50 mm for measuring aggregates.

5. Tamping rod 10 mm in diameter and 230 mm long, rounded at one end. 6. Sieve 12.5, 10, and 2.36 mm. 7. Balance of capacity 500 g x 0.1 g 8. Oven (thermostatically)

IMPACT TESTING MACHINE THEORY:

The property of a material to resist impact is known as toughness. Due to movement of vehicles on the road the aggregates are subjected to impact resulting in their breaking down into smaller pieces. The aggregates should therefore have sufficient toughness to resist their disintegration due to impact. This characteristic is measured by impact value test. The

aggregate impact value is a measure of resistance to sudden impact or shock, which may differ from its resistance to gradually applied compressive load.

In other words, Resistance of the aggregates to impact is termed as toughness. Aggregates used in the pavement should be able to resist the effect caused by the jumping of the steel tyred wheels from one particle to another at different levels causes severe impact on the aggregates.

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 8 PROCEDURE:

1. Oven dried aggregate specimen passing 12.5 mm sieve and retained on 10 mm sieve is filled in measuring cup in three equal layers by 25 blows with the help of tamping rod and weighed.

2. The sample is now transferred to the cup of the impact test apparatus and compacted by tamping rod 25 times again in 3 equal layers.

3. Now the hammer is raised to a height of 38 (±0.5) cm above the surface of the aggregate in the cup and is allowed to fall freely in the specimen. In this 15 blows are given to the aggregate specimen at an interval of not less than one second between successive falls.

4. Now the tested aggregate sample is sieved through 2.36 mm I.S. Sieve and the fraction passing or retained through this sieve is weighed.

OBSERVATION & CALCULATIONS

RESULT

Aggregate Impact Mean Value = ………% INTERPRETATION OF RESULTS

Aggregate impact value is used to classify the stones in respect of their toughness property as indicated below;

S No Aggregate impact value Classification

1 < 10 % Exceptionally Strong

2 10 – 20 % Strong

3 20 – 30 % Satisfactory for road surfacing 4 >35 % Weak for road surfacing

The Indian Road Congress has recommended the following values for different types of road construction.

S No Type of pavement Max. Permissible Aggregate Impact Value %

1 WBM Sub base/base course 30

2 WBM wearing course 30

3 Dense Bituminous Macadam & SDBC 27

4 Bituminous Concrete (BC) 24

S.No. Determinations 1 2

1. Weight of measuring cylinder, W1 gm

2. Weight of measuring cylinder + aggregates, W2 gm

3. Weight of aggregate sample filling the cylindrical measure, Wa= W2-W1 gm

4. Weight of aggregate retained on 2.36 mm sieve after the test = W3 g

5. Weight of aggregate passing through 2.36 mm sieve after the test = Wa-W3 g

6. _{Aggregate impact value = percent fines =} 3 ₁₀₀

  a a W W W

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 9 DISCUSSION:

Write the discussion/suitability of aggregate according to your result obtained. PRECAUTIONS

1. Place the plunger centrally so that it falls directly on the aggregate sample and does not touch the walls of the cylinder in order o ensure that the entire load is transmitted on o the aggregates.

2. In the operation of sieving the aggregates through 2.36 mm sieve the sum of weights of fractions retained and passing the sieve should not differ from the original weight of the specimen by more than 1 gm.

3. The tamping is to be done properly by gently dropping the tamping rod and not by hammering action. Also the tamping should be uniform over the surface of the aggregate taking care that the tamping rod does not frequently strike against the walls of the mould.

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 10 Experiment No-3

AGGREGATE CRUSHING VALUE TEST

OBJECTIVE:

1. To determine the crushing value of given road aggregates;

2. To assess suitability of aggregates for use in different types of road pavements. APPARATUS/EQUIPMENTS REQUIRED:

1. Steel cylinder/test mould of 15.2 cm internal diameter with base plate and plunger. The height of the cylinder may vary from 13 to 14 cm. The thickness of cylinder walls may be 1.6 cm.

2. Cylindrical measure of internal diameter 11.5 cm. and height 18 cm.

3. A straight steel/metal tamping rod 45 to 60 cm. long and 1.6 cm diameter having a pointed/rounded end.

4. Compression testing machine capable of applying load of 40 tones, at a uniform rate of loading of 4 tons per minute.

5. Balance of cap. 5.0 kg with accuracy up to 1 g 6. IS Sieves of 12.5 mm, 10 mm and 2.36 mm.

7. A Compression Testing Machine capable of applying load upto 40 tones at a uniform rate of 4 tones per minute.

Compression Testing Machine-Cap 2000 kN Steel Cylinder, Cylindrical Measure, Tamping Rod and Plunger

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 11 THEORY:

One of the model in which pavement material can fail is by crushing under compressive stress. This test is used to determine the crushing strength of aggregates. The aggregate crushing value provides a relative measure of resistance to crushing under gradually applied crushing load. The principal mechanical properties required in road stones are (i) satisfactory resistance to crushing under the roller during construction and (ii) adequate resistance to surface abrasion under traffic. Also surface stresses under rigid tyre rims of heavily loaded and drawn vehicle are high enough to consider the crushing strength of road aggregates as essential requirements in India.

PROCEDURE:

1. Aggregate passing 12.5 mm I.S. sieve and retained on 10 mm sieve is taken and dried. 2. This aggregate filled in the cylindrical measure in three equal layers and each layer

tamped 25 times by the tamping rod.

3. Now the test sample is weighed and filled in the test cylinder in three equal layers and tamped each layer 25 times. Let the weight of aggregate be W1 Kg.

4. Now the plunger is placed on the top of the test specimen and whole apparatus is put in the compression testing machine.

5. Now the specimen is loaded to a total load of 40 tones at the rate of 4 tons per minute i.e., the total load s reached in 10 minutes in the compression machine.

6. Now the test cylinder is removed from the compression machine and aggregate sieved through 2.36 mm sieve. The material passed through the 2.36 mm sieve is weighed. Let the weight be W2 Kg.

OBSERVATION & CALCULATIONS:

S. No. Details Trial No.

1 2

1. Empty weight of measuring cylinder, W1

2. Wt of measuring cylinder with aggregate, W2

3. Weight of aggregate sample filling the cylindrical measure = Wa =

2

W - W1 g

4. Weight of aggregate retained on 2.36 mm sieve after the test, W3g

5. Weight of aggregate passing 2.36 mm sieve after the test ,W4 =

a

W - W3 g

6. _{Aggregate crushing value (%fines) =} 4 ₁₀₀



a

W W

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 12 RESULT:

Aggregate Crushing Value = ………% PRECAUTIONS:

1. The plunger should be placed centrally and rest directly on the aggregates. Care should be taken that it does not touch the walls of the cylinder so as to ensure that the entire load is transferred onto the aggregates.

2. In the operation of sieving the aggregates through 2.36 mm sieve and weighing care should be taken to avoid loss of fines. The sum of weights of fractions retained and passing the sieve should not differ from the original weight of the specimen by more than 1 gm.

3. The tamping should be done properly by gently dropping the tamping rod and not by hammering action. Also the tamping should be uniform over thy surface of the aggregates taking care that the tamping rod does not frequently strike against the walls of the mould.

INTERPRETATION OF RESULTS:

The suitability of aggregate is adjudged, dependent upon its proposed use in the pavement layers. The table given below lays down specified limits of percent aggregate crushing value, for different types of road construction.

S No Type of Pavement Max. permissible aggregate crushing value %

1 WBM Sub base/base course 40

2 WBM wearing course 30

3 DBM/BC/SDBC 30

4 Cement Concrete 30

DISCUSSION:

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 13 Experiment No-4

FLAKINESS & ELONGATION INDEX (SHAPE TEST) OF AGGREGATE

OBJECTIVE:

1. To determine the flakiness index and,

2. To determine the elongation index of given aggregates sample.

3. To assess suitability of aggregates for use in different types of road pavements INTRODUCTION:

The particle shape of aggregates is determined by the percentages of flaky and elongated particle contained in it. In the case of gravel it is determined by its angularity number. For base

course and construction of bituminous and cement concrete types, the presence of flaky and elongated particles are considered undesirable as they may cause inherent weakness with

possibilities of breaking down under heavy loads.

Rounded aggregates are preferred in cement concrete road construction as the work ability concrete improves. Angular shapes of particles are desirable for granular base course due to

increase stability divided from the better interlocking. When the shape of aggregates deviates more from the spherical shape, as in the case of angular, flaky and elongated aggregate, the void content in aggregate of any specified size increases and hence the grain size distribution of a graded aggregate has to be suitable altered in order to obtain minimum voids in the dry mix of the highest dry density.

The angularity number denotes the void content of single sized aggregates in excess of that obtained with spherical aggregates of the same size. Thus angularity number has considerable importance in the gradation requirements of various types of mixes such as bituminous concrete and soil-aggregate mixes.

The evaluation of shape of the particles, particularly with reference to flakiness, elongation an

angularity is necessary.

APPARATUS:

The apparatus consists of;

1. A standard Thickness & Length Gauge

2. I.S. Sieves of sizes 63, 50, 40, 31.5,25, 20, 16, 12.5, 10 and 6.3 mm. 3. A balance of cap 5 kg to weigh the samples.

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 14 THICKNESS GAUGE SET OF SIEVES

THEORY:

The flakiness index of an aggregates is the percentage by weight of particles whose least dimension (thickness) is less than three-fifths (0.6) of their mean dimension. The test is not applicable to sizes smaller than 6.3 mm.

The elongation index of an aggregate is the percentage by weight of particles whose greatest dimension (Length) is greater than 1.8 times of their mean dimension .The elongation index is not applicable to sizes smaller than 6.3 mm

THICKNESS AND LENGTH GAUGES DIMENSIONS (IS: 2386 (Part 1) -1963)

Size of Aggregate Thickness gauge (0.6 times the mean sieve) mm

Length gauge (1.8 times the mean sieve), mm Passing Through IS sieve mm Retained on IS sieve mm 63.0 mm 50 mm 33.90 --- 50.0 mm 40 mm 27.00 81.0 40.0 mm 25 mm 19.50 58.5 31.5 mm 25 mm 16.95 --- 25.0 mm 20 mm 13.50 40.5 20.0 mm 16 mm 10.80 32.4 16.0 mm 12.5mm 8.55 25.6 12.5 mm 10.0 mm 6.75 20.2 10.0 mm 6.3 mm 4.89 14.7

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 15 PROCEDURE:

Determination of Flakiness Index;

1. A sufficient quantity of aggregate is taken such that a minimum number of 200 pieces of any fraction can be tested.

2. Each fraction is gauged in turn for thickness on the meal gauge.

3. The total amount passing in the gauge is weighed to an accuracy of 0.1 per cent of the weight of the samples taken.

4. The flakiness index is taken as the total weight of the material passing the various thickness gauges expressed as a percentage of the total weight of the sample taken.

Determination of elongation Index

1. This test is conducted by using metal length gauge of the description. A sufficient quantity of aggregate is taken to provide minimum number of 200 pieces of any fraction to be tested.

2. Each fraction shall be gauged individually for length on the metal gauge.

3. The total amount retained by the gauge length shall be weighed to an accuracy of at least 0.1 per cent of the weight to the test samples taken.

4. The elongation index is the total eight of the material retained on the various length gauges expressed as a percentage of the total weight of the sample gauged.

OBSERVATION SHEET

Size of aggregate Weight of the fraction consisting of at least 200 pieces, gm Thickness gauge size mm Weight of aggregates in each fraction passing thickness gauge, gm Length gauge size mm Weight of aggregates in each fraction retained on length gauge, gm Passing through is sieve, mm Retained on IS sieve, mm 1 2 3 4 5 6 7 63 50 W1 = 23.90 w1 = -- -- 50 40 W2 = 27.00 w2 = 81.0 x1 = 40 25 W3 = 19.50 w3 = 58.5 x2 = 31.5 25 W4 = 16.95 w4 = -- -- 25 20 W5 = 13.50 w5 = 40.5 x3 = 20 16 W6 = 10.80 w6 = 32.4 x4 = 16 12.5 W7 = 8.55 w7 = 25.6 x5 = 12.5 10.0 W8 = 6.75 w8 = 20.2 x6 = 10.0 6.3 W9 = 4.89 w9 = 14.7 x7 = Total ∑W = ∑w = ∑x =

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 16 CALCULATIONS: Flakiness Index =

















1. Use safety shoes, mask & aprons at the time of test.

2. Special care should be taken that no outer air enters when using the balance. 3. All parts of the equipment should always be kept clean.

4. After the end of the test sieve should be clean by smooth brush.

DISCUSSIONS:

The presence of elongated particles in excess of 10 to 15 per cent is generally considered undesirable, but no recognized limits are laid down. Indian standard explain only the method of calculating both flakiness index and elongation index. But the specifications do not specify the limits. British standard BS 882 of 1992 limits the flakiness index of the coarse aggregate to 50 for natural gravel and to 40 for rushed coarse aggregate. However, for wearing surfaces lower

values of flakiness index are required.

INTERPRETATION OF RESULTS:

Indian Road Congress (IRC: 111-2009), NRRDA (2007) and MORTH (2000) have recommended the values of flakiness & elongation index as follows;

S No Type of Pavement Maximum Permissible Value %

Flakiness Index Elongation Index

1 WBM Sub base course 30 30

2 WBM base course 25 25

3 WBM wearing course 20 20

4 DBM/BC/SDBC 35 35

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 17 Experiment No-5

FLASH AND FIRE POINT TEST OF BITUMEN

OBJECTIVE:

To determine the flash and fire point of given bitumen sample. APPARATUS/EQUIPMENTS REQUIRED:

1. Pensky-Martens closed tester consists of cup, lid, stirring device, cover, shutter, flame, exposure device etc.

2. Pensky-Martens open tester as above with the modification, that the cover of the cup is replaced by a clip which encircles the upper rim of the cup and carries thermometer and test flame.

3. Thermometer : 90 to 370oC, Graduation 2oC 4. Heater

Pensky-Martens Open Tester Pensky-Martens Closed Tester

THEORY:

This test is done to determine the flash point and the fire point of asphaltic bitumen and fluxed native asphalt, cutback bitumen and blown type bitumen as per IS: 1209 – 1978. The principle behind this test is given below:

Flash Point – The flash point of a material is the lowest temperature at which the application of

test flame causes the vapours from the material to momentarily catch fire in the form of a flash under specified conditions of the test.

Fire Point – The fire point is the lowest temperature at which the application of test flame

causes the material to ignite and burn at least for 5 seconds under specified conditions of the test.

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 18 PROCEDURE:

A) Flash Point

1. Soften the bitumen between 75 and 100oC. Stir it thoroughly to remove air bubbles and

water.

2. Fill the cup with the material to be tested upto the filling mark. Place it on the bath. Fix the open clip. Insert the thermometer of high or low range as per requirement and also the stirrer at a rate of approx 60 revolutions per minute, to stir it.

3. Light the test flame, adjust it. Supply heat at such a rate that the temperature increase, recorded by the thermometer is neither less than 5oC nor more than 6oC per minute.

4. Open flash point is taken as that temperature when a flash first appears at any point on the surface of the material in the cup.

5. Take care that the bluish halo that sometimes surrounds the test flame is not confused with the true flash.

6. Discontinue the stirring during the application of the test flame.

7. Flash point should be taken as the temperature read on the thermometer at the time the flash occurs.

B) Fire Point

1. After flash point, heating should be continued at such a rate that the increase in temperature recorded by the thermometer is neither less than 5oC nor more than 6oC per minute

2. The test flame should be lighted and adjusted so that it is of the size of a bead 4mm in dia.

OBSERVATION

1. Bitumen grade /cutback type and grade: ……… 2. Type of equipment: Closed cup/Open cup: ………

Rate of heating

Time in minutes 1 2 3 4 5 6 7 8 9 10 11 12

Temperature, °C

Test property Test Number Mean value

1 2 3

1. Flash point 2. Fire point

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 19 RESULT

1. Flash Point = …………..°C 2. Fire Point = ……….°C

PREACAUTIONS:

1. The test flame should neither be larger than stipulated nor be applied more frequently than specified as the surface layer may get super heated.

2. The bluish halo that sometimes surrounds the test flame should not be confused with the true flash.

INTERPRETATION OF RESULTS

The determination of flash point is helpful in assessing the safe limits of heating the bitumen. The heating temperature of bitumen should be limited well below the flash point. IS: 73-1992 & 2006 have recommended the value of flash point as follows;

Reference: - IS: 73-1992 Reference:- IS: 73-2006 Cleveland Open Cup, °C, Min Cleveland Open Cup, °C, Min

Requirements for Paving Bitumen Type-1 Requirements for P.B. Type-2 Requirements for Paving Bitumen S-35 S-45 S-55 S-65 S-90 S-200 A-35 A-55 A-65 A-90 VG-10 VG-20 VG-30 VG-40

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 20 Experiment No-6

DUCTILITY TEST OF BITUMEN

OBJECTIVE:

1. To measure the ductility value of bitumen.

2. To determine the suitability of bitumen for its use in road construction. THEORY:

Ductility is a measure of elasticity of adhesiveness of bitumen. It is expressed as the distance in centimeters to which a standard briquette of bitumen can be stretched before the thread breaks. As per I.S. 1208-1958, the test should be conducted at 27±0.5° C and the pull should be

applied at the rate of 50±2.5 mm per minute. The minimum width of cross-section should be 10×10 mm.

APPARATUS /EQUIPMENTS REQUIRED:

The apparatus for the standard ductility test as per IS: 1208-1978 consists of the following; 1. Briquette mould of following dimensions

Total length = 75.0±0.5 mm Distance between clips=30±0.3 mm Width at mouth of clip = 20±0.2 mm Width at min cross section = 10±0.1 mm Thickness throughout = 10±0.1 mm

2. Pulling device with distance measuring dial. 3. Water bath arrangement.

4. Knife. 5. Heater. 6. Thermometer. 7. Glycerin.

Briquette Mould Ductility Test Apparatus PROCEDURE:

1. The bitumen sample is heated at the temperature between 75 to 100 deg C to bring it in fluid state.

2. In order to prevent the material under test from sticking, coat the surface of the plate and interior surface of the sides of the mould with a mixture of glycerin and dextrin. 3. Pour the heated bitumen in the briquette assembly and placed on a brass plate.

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 21 4. The whole assembly including bitumen briquette along with brass plate is allowed to

cool in air for about 30 to 40 minutes.

5. The excess bitumen is cut and surface is leveled with the help of a hot knife.

6. The whole assembly now is kept in a water bath maintained at 27±0.5°C for about 85 to 95 minutes.

7. The side of the mould removed, the clips hooked on the machine and the pointer adjusted to zero value or initial reading noted.

8. Now the clips are pulled apart horizontally at the rate of 50.0 ± 2.5 mm per min. and the distance up to the point of breaking of thread is noted. This distance in centimeter gives the value of ductility of bitumen.

9. The ductility of bitumen may vary from 5 to 100 for different bitumen grades, but for satisfactory performance it should not be less than 50.

OBSERVATION:

1. Weight of sample (same for all samples) = ………. 2. Test temperature (same for all samples) = ………. 3. Grade of bitumen (same for all samples) =……….. 4. Ductility in cm.

Sample No. Ductility in cm 1

2 3

RESULT

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 22 PRECAUTIONS:

1. The plate assembly upon which the mould is placed shall be perfectly flat and level so that the bottom surface of the mould touches it throughout.

2. In filling the mould, care should be taken not to disarrange the parts and thus distort the briquette and to see that no air pocket shall be within the mould.

INTERPRETATION OF RESULTS

A normal test is one in which the material between the two clips pulls out to a point or to a thread and rupture occurs where the cross-sectional area is minimum. Report the average of three normal tests as the ductility of the sample, provided the three determinations be within ± 0.5 percent of their mean value.

If the values of the three determinations do not lie within ± 0.5 percent of their mean, but the two higher values are within ± 0.5 percent of their mean, then record the mean of the two higher values as the test result.

Reference: - IS: 73-1992 Reference:- IS: 73-2006 Ductility at 27°C, cm, Min Ductility at 25°C, cm, Min

Requirements for Paving Bitumen Type-1 Requirements for P.B. Type-2 Requirements for Paving Bitumen S-35 S-45 S-55 S-65 S-90 S-200 A-35 A-55 A-65 A-90 VG-10 VG-20 VG-30 VG-40

50 75 75 75 75 _--- 10 15 15 15 75 50 40 25

DISCUSSION:

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 23 Experiment No-7

PENETRATION TEST OF BITUMEN

OBJECTIVE:

1. To determine the Penetration value of the Bitumen.

2. To determine the suitability of bitumen for its use under different climatic condition and type of construction

APPARATUS/EQUIPMENTS REQUIRED: 1. Container: a flat bottomed cylindrical

metallic dish

For penetration below 225

Diameter in mm = 55 Internal depth in mm = 35

For penetration above 225

Diameter in mm = 70 Internal depth in mm = 45

2. Water bath: maintained at 25±0.1°C 3. Penetrometer as shown in figure 4. Transfer dish or tray

5. Therometer, Range 0-45 Deg C

6. Needle: A straight, highly polished, cylindrical hard steel, as per following dimension

THEORY:

This test is applied almost exclusive bitumen. For tars, cutback and emulsions other consistency are used. This test determines the hardness or softness of bitumen by measuring the depth in millimeter to which a standard loaded needle will penetrate vertically in 5 seconds while the temperature of the bitumen sample is maintained at 25°C.

This test is widely used world over for classifying the bitumen into different grades. 80/100

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 24 PROCEDURE:

1. The bitumen is softening to a pouring consistency at a temperature not more than 60°C for tars and 90°C for bitumen and Stir it thoroughly to remove air bubbles and water.

2. Pour it into a container to a depth of at least 15mm in excess of the expected penetration.

3. Cool it at an atmospheric temperature of 15 to 30°C for 1 to 1.5 hours for 35 mm depth container and 1.5 to 2 hrs for 45 mm deep container. Then place it in a transfer dish in the water bath at 25.0 + 0.1°C and allow it to remain for 1 to 1.5

hours for 35 mm deep container and 1.5 to 2 hrs for 45 mm deep container.

4. At the end of one hour, the sample is taken out of water bath and needle is brought in contact with the surface of bitumen sample and the reading of dial is set at zero or the reading of dial noted, when the needle is in contact with the surface of the sample.

5. Now the needle is released and allowed to penetrate for 5 seconds and the final reading is recorded on the same sample at least three penetration observations should be taken at distances at least 10 mm apart. After each test, the sample needle is disengaged, wiped wit benzene or petrol and dried.

6. The mean value of three measurements is reported as penetration test.

7. The accuracy of the test depends upon pouring temperature, size of needle, weight placed on needle, and test temperature.

OBSERVATION:

1. Pouring temperature, °C = ……… 2. Period of cooling in atmosphere, minutes = ………. 3. Room temperature, °C = ……….. 4. Period of cooling in water bath, minutes = ……….. 5. Actual test temperature, °C = ………..

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 25

Readings Trial Numbers

1 2 3 4 5

Penetrometer dial reading initial Penetrometer dial reading final Penetration value

Average penetration value RESULT

Avg. Penetration of the given bitumen sample = ………..

PRECAUTIONS:

1. There should be no movement of the container while needle is penetrating into the sample.

2. The sample should be free from any extraneous matter.

3. The needle should be cleaned with benzene or petrol and dried before each penetration.

INTERPRETATION OF RESULT

The grade of bitumen is specified in terms of penetration value. 30/40 grade bitumen indicates the penetration value of the bitumen in the range of 30 to 40 at standard test conditions. Penetration test is applied exclusively to bitumen. Tars being soft, penetration test on these materials cannot be carried out.

Reference: - IS: 73-1992 Reference:- IS: 73-2006 Ductility at 27°C, cm, Min Penetration at 25°C, 100 g, 5 sec

Requirements for Paving Bitumen Type-1 Requirements for P.B. Type-2 Requirements for Paving Bitumen S-35 S-45 S-55 S-65 S-90 S-200 A-35 A-55 A-65 A-90 VG-10 VG-20 VG-30 VG-40

30-40 40-50 50-60 60-70 80-100 175-225 30-40 50-60 60-70 80-100 80-100 60-80 50-70 40-60

DISCUSSION:

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 26 Experiment No-8

SOFTENING POINT TEST

To determine the softening point of bitumen by ring & ball apparatus. APPARATUS/EQUIPMENTS REQUIRED:

1. Brass Ring- 2 nos of following size Depth : 6.4±0.1 mm Inside dia at bottom : 15.9±0.1 mm Inside dia at top : 17.5±0.1 mm Outside dia : 20.6±0.1 mm

2. Steel ball-2 nos of 9.5 mm dia & weighing 3.50±0.05 g 3. Water bath-a heat resistance glass vessel 85 mm dia and

120 mm depth 4. Mechanical Stirrer. 5. Thermometer upto 100° C 6. Metallic support CONCEPT AND SIGNIFICANCE:

Softening point is defined as the temperature at which a substance attains a particular degree of softening under specified conditions of test. As per IS:334-1982, it is the temperature in deg C at which a standard ball passes through a sample of bitumen in a mould and falls through a height of 25 mm, when heated under water or glycerin at specified conditions of test. The binder should have sufficient fluidity before its applications in road uses. The determination of softening point helps to know the temperature upto which a bituminous binder should be heated for various road use applications. Softening point is determined by ring and ball apparatus. Usually softening point for different grades of bitumen used for pavements varies

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 27 PROCEDURE:

1. Sample material is heated to a temperature between 75 and 100°C above the approximate softening point until it is completely fluid.

2. Place the rings on a metal plate and coat its surface with mixture of glycerin and dextrin. 3. Fill the molten bitumen in the rings in sufficient quantity to give an excess above the

level of the ring.

4. Cool the specimen in air for about 30 minutes.

5. After cooling in air level the material in the ring by removing the excess with a warmed sharp knife.

6. The bitumen test sample placed in the brass ring is suspended in distilled water at a given temperature.

7. A steel ball is put on the bitumen and the water bath is heated such that the temperature of water bath rises by 5°C per minute.

8. The temperature at which the softened bitumen touches the metal plate placed at a specified distance (25 mm) below the ring is noted. This temperature is called the softening point of the bitumen. Higher the softening point, harder the grade of the bitumen.

OBSERVATION:

1. Bitumen grade: ………. 2. Approximate softening point: ………... 3. Liquid used in the bath: ……….. 4. Period of air cooling, minutes: ……….…. 5. Period of cooling in water bath, minutes = ……….….

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 28 RATE OF HEATING:

Time ( minutes) Temperature (°C) Time (minutes) Temperature (°C)

1 9 2 10 3 11 4 12 5 13 6 14 7 15 8 16 OBSERVATION TABLE:

Test property Trial-1 Trial-2 Mean value

softening point Ball Number Ball Number

(i) (ii) (i) (ii) Temperature(°C) at which

sample touches bottom plate RESULTS:

Avg. Value of Softening point = ………….Deg C

PRECAUTIONS:

1. Distilled water should be used as the heating medium

2. During the conduct of test the apparatus should not be subjected to vibrations. 3. The bulb of the thermometer should be at about the same level as the rings. INTERPRETATION OF RESULTS:

Softening point indicates the temperature at which binders possess the same viscosity. Bituminous materials do not have a definite melting point. Rather the change of state from solid to liquid is gradual and over a wide range of temperature. Softening point has particular significance for materials that are to be used as joint and crack fillers. Higher softening point ensures that they will not flow during service. In general, the higher the softening the lesser the temperature susceptibility. Bitumen with higher softening point may be preferred in warmer places.

Reference: - IS: 73-1992 Reference:- IS: 73-2006

Requirements for Paving Bitumen Type-1 Requirements for P.B. Type-2 Requirements for Paving Bitumen S-35 S-45 S-55 S-65 S-90 S-200 A-35 A-55 A-65 A-90 VG-10 VG-20 VG-30 VG-40

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 29 Experiment No-9

CENTRIFUGE EXTRACTOR TEST

OBJECTIVE

To determine quantity of bitumen in hot mix paving mixtures and pavement samples. APPARATUS

1. Centrifuge extractor: consists of a revolving bowl inside housing. The bowl is provided with a cover plate and it is secured in position by tightening the nuts. 2. The Bowl housing: is provided with an outlet, the

housing is mounted on nuts. 3. Filter paper,

4. Balance

5. Commercial benzene or petrol 6. A sample of 500 gm.

CONCEPT AND SIGNIFICANCE

The Centrifuge Extractor is used for the quantitative determination of bitumen in hot-mixed paving mixtures and pavement samples, essentially as a field test to exercise quality control and ensure that the specified amount of bitumen has been used. The bitumen content is calculated by difference of the weight of the extract aggregate, moisture content and ash from the weight of the sample taken for the test.

PROCEDURE TO DETERMINE BITUMEN CONTENT 1. Weigh a 500 gm sample of asphalt/bitumen mix.

2. If the mixture is not soft enough to separate with a trowel, place 1000g of it in a large pan and warm upto 100oC to separate the particles of the mixture uniformly.

3. Place the sample in the bowl and weigh it.

4. Cover the sample in the bowl with benzene or tri-chloromethane or petrol and allow it to soak for half an hour.

5. Weigh filter paper, place it around the edge of the bowl and clamp a lid on the bowl. 6. Place a beaker or big jar under the outlet.

7. Place the bowl in a centrifuge extractor.

8. Start the centrifuge extractor, revolving slowly and gradually increase the speed until the solvent ceases to flow from the outlet.

9. Stop the centrifuge, add 200 ml of tri-chloromethane or benzene or petrol and rotate it again.

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 30 10. Repeat the procedure (not less than 3 washings) until the extract is no longer cloudy and

is fairly light in color.

11. Remove the filter paper from the bowl and dry in air. 12. Brush the loose particles from the filter into the bowl

13. Dry the filter to constant weight in an oven at 980 C to 105o C. 14. Obtain the weight of the filter and bowl with dry aggregates OBSERVATIONS & CALCULATIONS:

S.No Particulars Trial-1 Trial-2 Trial-3

BEFORE TEST

1. Weight of bowl + sample (W1), g

2. Weight of bowl (W2) g

3. Weight of filter (W3), g

AFTER TEST

4. Weight of bowl + sample (W4),g

5. Weight of filter (W5), g

6. Weight of sample (W1-W2), g

7. Weight of aggregates in bowl (W4-W2), g

8. Weight of aggregates in filter (W5-W3), g

9. Weight of aggregates WA = (W4-W2) + (W5-W3) 10. Weight of bitumen, WB = (W1-W2) - WA 11. _{Bitumen content =} 100% A B W W REPORTING OF RESULTS:

Bitumen Content in given sample = …………. % PRECAUTIONS

1. Separate the particles of the mixture as uniformly as possible taking care not to fracture the mineral particles.

2. The cover plate should be fixed tightly on the bowl.

INTERPRETATION OF RESULTS:

The results of the test are an indication regarding the quantity of bitumen that has been used in bituminous mix. By performing this field test a substantial saving in the cost of bitumen can be had by ensuring that the optimum quantity of bitumen has been provided. Also the performance of the road will be affected if lesser or more quantity of bitumen is used.

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 31 Experiment No-10

MARSHALL STABILITY TEST

OBJECTIVES

1. To determine the strength (Marshall Stability Value) and flexibility (flow value) for the given bitumen mixture.

2. To determine the density-voids analysis for the given bituminous mixture;

3. To determine the suitability of bituminous mixture to meet the specified criteria for the surface course.

INTRODUCTION

Bruce Marshall, formerly bituminous engineer with Mississippi State Highway Department, USA formulated Marshall Method for designing bituminous mixes.

This test is done to determine the Marshall stability of bituminous mixture. The

principle of this test is that Marshall Stability is the resistance to plastic flow of cylindrical specimens of a bituminous mixture loaded on the lateral surface at 5 cm per minute. It is the load carrying capacity of the mix at 60oC and is measured in kg.

The sample needed is From Marshall stability graph, select proportions of coarse aggregates, fine aggregates and filler in such a way, so as to fulfill the required specification. The total weight of the mix should be 1200 gm for one specimen.

CONCEPT AND SIGNIFICANCE

The test procedure is used in designing and evaluating bituminous paving mixes and is

widely applied in routine test programmes for the paving jobs. The major features of the Marshall Method of designing mixes are to determine the two important properties of

strength and flexibility.

Strength is measured in terms of the “Marshall’s Stability” of the mix which is defined as the maximum load carried by a compacted specimen at a standard test temperature of 600C. This temperature represents the weakest condition for a bituminous pavement in use.

The flexibility is measured in terms of the “Flow Value” which is measured by the change in diameter of the sample in the direction of lad application between the start of loading and the time of maximum load. In this test an attempt is made to obtain

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 32 EQUIPMENT/APPARATUS

The apparatus for the Marshall Stability test consists of the following:

1. Specimen Mould Assembly comprising mould cylinders 10 cm diameter x 7.5 cm

height, base plate and extension collars. They are designed to be interchanged with

either end of cylindrical mould. Three mould cylinders are recommended.

2. Specimen extractor for extracting the compacted specimen from the mould. A suitable bar is required to transfer load from the extension collar to the upper proving ring attachment while extracting the specimen

3. Compaction Rammers having a flat circular tamping face 4.5kg sliding weight constructed to provide a free fall of 45.7cm. Two compaction rammers are recommended.

4. Compaction pedestal consisting of a 20 x 20 x 45 cm wooden block capped with a 30

x 30 x 2.5 cm MS plate to hold the mould assembly in position during compaction.

Mould holder is provided consisting of spring tension device designed to hold compaction mould in place on the compaction pedestal.

5. Breaking head. The Breaking head consist of upper and lower cylindrical segments or test heads having an inside radius curvature of 5 cm. The lower segment is mounted on a base having two perpendicular guide rods which facilitate insertion in the holes of upper test segments. assembly with provision to fix flow meter

6. Loading Machine motorized, loading machine is provided with a gear system to lift the upward direction. Recalibrated proving ring of 5 tone capacity is fixed on the upper end of the machine, specimen contained in the test head is placed in between the base and the proving ring. The loading jack produces uniform vertical movement of 5 cm/ min. Machine is capable of reversing its movement downward also. This facilitates adequate space for placing test head system. After one specimen has been tested.

7. Flow Meter. The flow meter consists of guide sieve and a gauge. The activating pin of the gauge slides inside the guide sleeve with a slide amount f fractional resistance. Least count of 0.025mm is adequate. The flow value refer top the total vertical upward movement form the initial position at zero load to value at maximum load. The dial; gauge at the flow meter should be able to measure accurately the total vertical movement upward.

In addition to the above the following general equipments are also required  Oven or hot plates

 Mixing Apparatus  Water Bath

 Thermometer of range up to 2000C with sensitively of 2.5 degree Celsius  Miscellaneous Equipments are like container, mixing and handling tools etc.

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 33 Bitumen Mixer, Digital & Manual Compactor, Moulds and Marshall Stability Test Apparatus PREPARATION OF TEST SPECIMEN

The coarse aggregates, fine aggregates, and the filler materials should be proportioned so as to fulfill the requirements of the relevant standards. The required quantity of the mix is taken so as to produce compacted bituminous mix specimens of thickness 63.5 mm approximately.

1. Take 1200 gm of coarse aggregates, fine aggregates and filler material (as per grading requirement given in table) to produce the desired thickness.

2. The aggregates are heated to a temperature of 175° to 190°C the compaction mould assembly and rammer are cleaned and kept pre-heated to a temperature of 100°C to 145°C.

3. The bitumen is heated to a temperature of 121°C to 138°C and the required amount of

first trial of bitumen is added to the heated aggregate and thoroughly mixed using a mechanical mixer or by hand mixing with trowel.

4. The mixing temperature for 110 grade bitumen may be around 154°C and that for 60/70 grade about 160°C.

5. The total quantity of mix is placed in a mould and compacted by rammer with 75 blows. Invert the sample, and compact the other face with the same number of blows.

6. The compacting temperature should be about 138°C for 80/100 grade bitumen and 149°C for 60/70 grade.

7. After compaction, invert the mould. With the collar of the bottom, remove the base and extract the sample by pushing it out the extractor.

8. The compacted specimen should have a thickness of 63.5 mm. 9. Allow the sample to stand for a few hours to cool.

10. Obtain the sample’s mass in air and submerged, to measure density of specimen, so as to allow, calculation of the voids properties.

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 34 NOTES:

1. At least 2 specimens (but preferably 3 or 4 specimen) for each combination of aggregate and bitumen should be prepared.

2. For surface course with 12 mm aggregate, the expected optimum bitumen

content may be about 6.5 %. Therefore specimen should be made at 5.5 %, 6.0

%, 6.5 %, 7.0 % and 7.5 % bitumen content.

---

TABLE-7 OF IRC: 111-2009

AGGREGATE GRADING AND BITUMEN CONTENT

Specification D.B.M. S.D.B.C. B.C.

Grading 1 2 1 2 1 2

Nominal max aggregate size 37.5 mm 26.5 mm 13.2 mm 9.5 mm 19 mm 13.2 mm Layer thickness 75-100 50-75 40 25 50 25/40 S.No IS Sieve Size Cumulative Percent Passing By Weight of Total Aggregate

1 45 mm 100 2 37.5 mm 95-100 100 3 26.5 mm 63-93 90-100 100 4 19 mm -- 71-95 100 90-100 100 5 13.2 mm 55-75 56-80 90-100 100 59-79 90-100 6 9.5 mm -- -- 70-90 90-100 52-72 70-88 7 4.75 mm 38-54 38-54 35-51 35-51 35-55 53-71 8 2.36 mm 28-42 28-42 24-39 24-39 28-44 42-58 9 1.18 mm -- -- 15-30 15-30 20-34 34-48 10 600 microns -- -- -- -- 15-27 26-38 11 300 microns 7-21 7-21 9-19 9-19 10-20 18-28 12 150 microns -- -- -- -- 5-13 12-20 13 75 microns 2-8 2-8 3-8 3-8 2-8 4-10

14 Binder Content (Min) 4.0 % 4.5 % 4.5 % 5.0 % 5.2 % 5.4 % TABLE-6 OF IRC: 111-2009: GRADING REQUIREMENT OF MINERAL FILLER S.No IS Sieve Cumulative Percent Passing By Weight Of Total Aggregate

1 600 microns 100

2 300 microns 95 - 100

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 35 TEST PROCEDURE

1. In conducting the stability test, the specimen are heated at a temperature of 60

±10 C (37.8 ± 10C for specimens in which tar has been used in place bitumen),

either in a water bath for 30-40 minutes or in an oven for a minimum of 2 hours. 2. Remove the specimens from the water bath (or oven) and place the lower

segment of the breaking head. Then place the upper segment of the breaking head on the specimen and place the complete assembly in position of the Marshall testing machine.

3. Place the flow meter (dial gauge) over one of the post and adjust into read zero. 4. Apply a load at a rate of 50 mm per minute until the maximum load reading is

obtained.

5. Record the maximum load in Newton (N). At the same instant obtain the flow as recorded on the flow meter in unit of mm.

6. The total time between removing the specimen from the bath and completion of the test should not exceed 30 seconds.

RECORD OF OBSERVATIONS

1. Mass of aggregates in mixing pan = 1200 gm 2. Mass of bitumen added ……… gm 3. Bitumen content ……… % 4. Heating Temperature Aggregates ……… 0C Bitumen ………. 0C Mixing ……….0C

5. Compacting temperature ……… 0C 6. Number of blows with hammer per face ……… Nos 7. Mass of specimen in air ‘Wm” ………. gm

8. Mass submerged ‘Ww’ ……….. gm

9. Diameter of Specimen ………. cm 10. Thickness of specimen ………. cm 11. Volume of specimen ‘Vm’ ……….. cm3

NOTE:

1. The measured stability of a specimen multiplied by the ration for the thickness of specimen is equal to the corrected stability for a 63.5 mm specimen.

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 36 COMPUTATION OF RESULTS

S. No. Determinations Trial-1 Trial-2

1 Weight of Compacted Specimen , Wm in gm

2 Volume of Compacted Specimen, V_m .r2.h in cm3 3 Density of Compacted Specimen,

m m

V W

d  , g/cm3

4 Specific Gravity of Bitumen, Gb 0.99 0.99

5 Specific Gravity of Aggregate, Ga 2.70 2.70

6

Theoretical (Apparent) Specific Gravity of the Mix

b b agr agr b agr t b b b t G W G W W W G Or G W G W G W G W G W W W W W W G            







7 Bulk Specific Gravity of the Mix

w m m m W W W G   8 Percent Air Voids in Mix ,   100

t m t v G G G V

9 Percent Volume of Bitumen

m b b b b G W W W W W G W V      4 3 2 1

11 Percent Voids in Mineral Aggregates, VMAVvVb

12 Percent Voids Filled With Bitumen,  100 VMA

V

VFB b

13 Measured Stability in , kN or Newton (N) or Kg 14 Flow Value , mm

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 37

CORRECTION FACTOR

It is possible while making the specimen the thickness slightly vary from the standard specification of 63.5 mm. Therefore, measured stability values need to be corrected to those which would have been obtained if the specimens had been exactly 63.5 mm. This is done by

multiplying each measured stability value by an appropriated correlation factors as given in Table below.

Volume of Specimen in Cubic Centimeter Approximate Thickness of Specimen In mm Correction Factors 457 – 470 57.1 1.19 471 – 482 58.7 1.14 483 – 495 60.3 1.09 496 – 508 61.9 1.04 509 – 522 63.5 1.00 523 – 535 65.1 0.96 536 – 546 66.7 0.93 547 – 559 68.3 0.89 560 – 573 69.9 0.86

REQUIREMENTS OF DENSE GRADED BITUMINOUS MIX USING VG/MODIFIED BITUMEN REF: TABLE-8 OF IRC: 111-2009

Properties Viscosity Graded (VG)

Bitumen

Modified Bitumen Test Method Hot Climate Cold Climate

Compaction Level (No. of blows) 75 blows on each face of the specimen

Minimum Stability (kN at 60°C) 9.0 (900 Kg) 12.0 (1200 Kg) 10.0 (1000 Kg) AASHTO T245

Marshall flow (mm) 2 – 4 2.5 – 4 3.5 – 5 AASHTO T245 Marshall Quotient (Stability/flow) 2 – 5 2.5 – 5 2.5 – 5

% Air Voids 3 – 5 3 – 5 3 – 5 MS-2 & ASTM D2041 % Voids filled with bitumen (VFB) 65 – 75 65 – 75 65 – 75 MS – 2 Tensile strength ratio 80 % Minimum AASHTO T283 Coating of aggregate particle with

bitumen 95 % Minimum 95 % Minimum IS: 6241

% Voids in Mineral Aggregate, VMA

Nominal Max Particle Size (mm) Min % VMA related to designed % air voids

3 4 5 9.5 14 15 16 13.2 13 14 15 19.0 12 13 14 26.5 11 12 13 37.5 10 11 12

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 38 RELATIONSHIP BETWEEN BITUMEN CONTENT AND VARIOUS DESIGN PARAMETERS

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 39 Experiment No-11

BENKELMAN BEAM TEST

To determine the rebound deflection of a pavement under a standard wheel load and tyre pressure with or without temperature measurement by Benkelman Beam test.

INTRODUCTION

A.C. Benkelman devised the simple deflection beam in 1953 for measurement of pavement surface deflection on the WASHTO Test Road. It is widely used all over the world for evaluation of the requirements of strengthening of flexible pavements.

CONCEPT & SIGNIFICANCE:

Performance of flexible pavements is closely related to the elastic deflection of pavement under the wheel loads. The deformation or elastic deflection under a given load depends upon sub grade soil

type, its moisture content and compaction, the thickness and quality of the pavement courses, drainage conditions, pavement surface temperature etc.

The Benkelman Beam Deflection Method is thus widely used for Evaluation of Structural Capacity of Existing Flexible Pavements and also for Estimation and Design of Overlays for Strengthening of any

weak pavement for Highways.

DEFLECTION:

Pavement surface deflection measurements are the primary means of evaluating a flexible pavement structure and rigid pavement load transfer. Although other measurements can be made that reflect (to some degree) a pavement's structural condition, surface deflection is an important pavement

evaluation method because the magnitude and shape of pavement deflection is a function of traffic

(type and volume), pavement structural section, temperature affecting the pavement structure and moisture affecting the pavement structure.

Deflection measurements can be used in back calculation methods to determine pavement structural

layer stiffness and the sub grade resilient modulus. Thus, many characteristics of a flexible pavement can be determined by measuring its deflection in response to load. Furthermore, pavement deflection measurements are non-destructive.

EQUIPMENT/AAPARATUS:

Benkelman Beam consists of a slender beam 3.66 mtr long pivoted at a distance of 2.440 mtr from the tip as shown in fig below and a loaded truck (8 to 10 tons).

Prepared By: M.L. Rathore (Lab Engineer), Civil Engg Dept, JUET Guna (M.P.): 40 SALIENT FEATURES OF BENKELMAN BEAM:

 The equipment is light weight and made of aluminium for easy portability and

use at any test location.

 Length of the Benkelman beam is 250 cm and net weight is 15kg.

 The apparatus is compact, unique and possess a telescopic design for quick set up

and storage during transport to the test location.

 The equipment is supplied in two parts for assembling on site with easy hand

tools.

 One end of the beam rests at a point under investigation while the beam is

pivoted in the centre.

 The free end carries a dial gauge to record the deflections. The other end is kept

on a stable platform.

 Provided with anti-vibration system for accurate measurement of pavements.  Provided with dial indicator and accessories.

 The beam is put in contact with the pavement under test between the tires of

the vehicles.

 The measurement of the deflection is carried out when the vehicle passes over

the test area. UTILITY

 Direct reading of deflection dial indicators eliminates the need for conversions or

calculations during measurement.

 It is used to measure the deflection of the road surface when loaded by the

wheels of vehicles. ACCESSORIES

 Wooden carrying case for the Benkelman Beam  Benkelman indicator gauge, calibration unit, etc. APPLICATIONS

 Pavement structure analysis  Roadways construction

 Road surface deflection measurement  Plate test