The Marshall stability and flow test provides the performance prediction measure for the Marshall mix design method. The stability portion of the test measures the maximum load supported by the test specimen at a loading rate of 50.8 mm/minute. Load is applied to the specimen till failure, and the maximum load is designated as stability. During the loading, an attached dial gauge measures the specimen's plastic flow (deformation) due to the loading. The flow value is recorded in 0.25 mm (0.01 inch) increments at the same time when the maximum load is recorded.

1. MIX DESIGN OF BITUMEN USING
MARSHALL MIX DESIGN METHOD
Presented by :
Shailesh Sharma
Akhil Ahuja
Rajat Yadav

2. CONTENTS
1. Introduction.
2. Objectives.
3. Preparation of sample.
4. Marshall stability and flow test.
5. Results and Analysis.

3. INTRODUCTION
The basic concepts of the Marshall mix design method were originally developed by Bruce
Marshall of the Mississippi Highway Department around 1939 and then refined by the
U.S. Army.
The Marshall stability and flow test provides the performance prediction measure for the
Marshall mix design method. The stability portion of the test measures the maximum load
supported by the test specimen at a loading rate of 50.8 mm/minute. Load is applied to
the specimen till failure, and the maximum load is designated as stability. During the
loading, an attached dial gauge measures the specimen's plastic flow (deformation) due to
the loading. The flow value is recorded in 0.25 mm (0.01 inch) increments at the same time
when the maximum load is recorded.

4. OBJECTIVES
Determine the optimum bitumen content of a asphalt mix so that it gives maximum
stability.

5. DESIRABLE PROPERTIES
1. Stability
2. Durability
3. Flexibility
4. Skid resistance
5. Impervious layer

6. PREPARATION OF SPECIMEN
1. The coarse aggregates, fine aggregates and the filler
material should be proportioned and mixed as per
the dry mix design(1200gm).
2. he dry mix of aggregates and filler is heated to a
temperature of 150° to 170°C.
3. The compacted mould assembly and rammer are
cleaned and kept preheated to a temperature of 100°C
to 145°C.
4. The bitumen is heated to a temperature of 150°C to
165°C and the required quantity of the first trial
percentage of bitumen is added to the heated
aggregates and thoroughly mixed.
5. The mixing temperature of the 60/70 grade is about
165°C.

7. PREPARATION OF SPECIMEN
Marshall Mould
1. For preparing specimens of 10cm diameter and
6.35 cm height for Marshall testing.
2. Consists of base plate, forming mould and collar.
3. Interchangeable base plate and collar can be used
on either end of compaction mould.

8. PREPARATION OF SPECIMEN
Compaction of the Specimen
1. The mix is placed in the mould and compacted by a
rammer with about 75 blows on each side.
2. The weight of hammer is 4.54 kg and height of fall is
45.7 cm.
3. The compacting temperature may be about 135°C for
60/70 grade bitumen.
4. The compacted specimen should have a thickness of
63.5 ± 3.0mm.

9. PREPARATION OF SPECIMEN
Sample Extraction
Sample is being extracted after 24hr using Marshall machine.

10. MARSHALL STABILITY AND FLOW TEST
1. The specimens to be tested are kept immersed in water
in a thermostatically controlled water bath at 60 ± 1°C
for 30 to 40 minutes.
2. Take out the specimen from the water bath and place it
in the breaking head.
3. Place the breaking head in Marshall testing machine.

11. MARSHALL STABILITY AND FLOW TEST
4. Load is applied on the breaking head by the loading
machine at the rate of 5 cm per minute.
5. Stability value is the load taken by the specimen at
failure.
6. Flow value is the deformation of the specimen at
failure.
7. Apply correction factor to the stability value if the
height of specimen is different from 6.35 cm.

12. CORRECTION FACTORS

13. Result And Analysis
Specific Gravity
Coarse Aggregate (G1) = 2.42
Fine Aggregate (G2) = 2.8
Filler (G3) = 2.9
Bitumen (G4) = 0.99
Weight
Coarse Aggregate (w1) = 420gm
Fine Aggregate (w2) = 720gm
Filler (w3) = 60gm

14. Result And Analysis
Sample Bitume
n
Conten
t (%)
Weight
of
bitume
n (gm)
Volume
of
sample
(gm)
Gt Gm Vv Vb VMA VFB
1 3 36 524.9 2.53 2.35 7.11 6.91 14.02 49.28
2 3.4 40.8 522.4 2.52 2.37 5.95 7.87 13.8 56.95
3 3.8 45.6 514.56 2.50 2.41 3.7 8.9 12.6 70.63
4 4.2 50.4 525.5 2.49 2.37 2.62 9.73 13.34 77.8
*Gt = Theoretical Specific Gravity
* Gm = Unit Weight
*Vv = % Air Voids
* VMA = voids in mineral aggregate
* Vfb = Voids filled with bitumen
* Vb = % volume of bitumen

15. RESULT AND ANALYSIS
Sample no. Bitumen
content %
Stability value(Kg) Flow value
(mm)
Measured Corrected
1 3 1680 1612.8 2.22
2 3 2080 1996.8 3.15
Average 1804.8 2.68
3 3.4 1960 188106 3.09
4 3.4 2240 2240 3.53
Average 2060.8 3.31
5 3.8 2200 2200 3.81
6 3.8 2360 2454.4 2.51
Average 2327.2 3.16
7 4.2 2040 2040 4.01
8 4.2 1880 1880 4.34
Average 1960 4.175

16. STABILITY VS BITUMEN CONTENT
Bitumen
content (%)
stability
(Kg)
3 1804.8
3.4 2060.8
3.8 2327.2
4.2 1960

17. FLOW VALUE VS BITUMEN CONTENT
Bitumen
content (%)
Flow value
(mm)
3 2.98
3.4 3.31
3.8 3.67
4.2 4.175

18. VFB VS BITUMEN CONTENT
*VFB – Voids filled with bitumen
Bitumen
content (%)
VFB (%)
3 49.28
3.4 56.95
3.8 70.63
4.2 77.80

19. % AIR VOIDS IN MIX VS BITUMEN CONTENT
Bitumen
content (%)
Air voids
(%)
3 7.11
3.4 5.95
3.8 3.7
4.2 2.62

20. UNIT WEIGHT VS BITUMEN CONTENT
2.5 2.7 2.9 3.1 3.3 3.5 3.7 3.9 4.1 4.3
2.34
2.35
2.36
2.37
2.38
2.39
2.4
2.41
2.42
2.35
2.37
2.41
2.37
Bitumen content (%)
Unitweight
Bitumen
content (%)
Unit weight
3 2.35
3.4 2.37
3.8 2.41
4.2 2.37
*unit weight – Bulk specific gravity

21. OPTIMUM BITUMEN CONTENT
• Optimum Bitumen Content Bitumen content corresponding to maximum stability = 3.8 %
• Bitumen content corresponding to maximum bulk density = 3.8%
• Bitumen content corresponding to 4% air voids = 3.689%
• Optimum bitumen content of the mix (3.8+3.8+3.689)/3= 3.763% Flow Value corresponding
to 3.763 % bitumen content = 3.6637 mm.
• VFB at 3.763% = 70.47%

22. THANKYOU