Except:

1. Durability

2. Stability

3. Resistance to fatigue cracking

4. Resistance to thermal cracking

13. Short-term aging that occurs during production and placement of asphalt concrete is simulated by the following:

    1. Pressure Aging Vessel (PAV)

    2. Long-Term Oven Aging

    3. Dynamic Shear Rheometer (DSR)

    4. Rolling Thin Film Oven Test (RTFO)

14. If you achieved a degree of compaction of 98% and your bulk specific gravity is 2.67, you targeted a maximum theoretical specific gravity (G_mm) of:

a) 2.71

b) 2.72

c) 2.75

d) 2.80

15. If you need to make a specimen 10.16 cm in diameter and 7.62 cm high, and the target bulk specific gravity is 2.68, then the mass of the material used should be close to:

a) <1,400g b) 1,550g c) 1,650g d) >1,700g

16. Which of the following is NOT considered an aggregate property in asphalt concrete volumetric calculations?

    1. VMA

    2. G_sb

    3. G_mm

    4. G_se

17. In the aggregate, the effective volume (V_se) is generally the bulk volume (V_sb).

    1. Larger than

    2. The same as

    3. Smaller than

    4. 4 times as small as

    5. None of the above

18. The type of aging that occurs during mixing and compaction in the field is referred to as:

    1. Medium-term aging

    2. Long-term aging

    3. Short-term aging

    4. None of the above

19. The mixing and compaction temperatures of asphalt mixes are determined based on:

    1. Aggregate gradation

    2. Aggregate type

    3. Asphalt binder viscosity

    4. % air void

20. Select a correct match for the performances of asphalt concrete and test methods shown in the figure below:

    1. (B) Rutting; (C) Fatigue; (D) Thermal cracking

    2. (B) Fatigue; (C) Rutting; (D) Thermal cracking

    3. (B) Fatigue; (C) Thermal cracking; (D) Rutting

    4. (B) Thermal cracking; (C) Fatigue; (D) Rutting

21. As a materials engineer working for a highway department, what standard PG asphalt binder grade would you specify for each of the conditions shown in Table 1 (show all calculation and fill in the table)? (10 marks)

Table 1

Case	7-day pavement		Max. pavement temperature		Recommended PG grade
	Mean, oC	Std. Dev., oC	Mean, oC	Std. Dev., oC		50% Reliability	98% Reliability
1	43	1.5	-29	2.5		PG 46-34	PG 46-34
2	51	3	-18	4		PG 52-22	PG 58-28
3	62	2.5	10	2		PG 64-10	PG 70-10

1. Average 7-day Max Pavement Design Temperature ≥ 43+2*1.5 = 46 ºC

Minimum Pavement Design Temperature ≤ -29-2*2.5 = -34 ºC

2. Average 7-day Max Pavement Design Temperature ≥ 51+2*3 = 57 ºC

Minimum Pavement Design Temperature ≤ -18-2*4 = -26 ºC

3. Average 7-day Max Pavement Design Temperature ≥ 62+2*2.5 = 67 ºC

Minimum Pavement Design Temperature ≤ 10-2*2 = 6 ºC

22. Describe the component of emulsified asphalt (asphalt emulsion) and discuss how asphalt emulsions work as a binder in asphalt mixture. (5 marks)

Emulsion constituent: asphalt cement + water + emulsifying agent

Asphalt emulsion due to its viscosity and bending properties sticks aggregates in the asphalt mixture:

• Mixing – asphalt cement, water and emulsifying agent are mixed together

• Breaking – the process of separating the asphalt and water

• Curing – the process by which the asphalt expels water and dries to a film on the aggregate or surface

23. As discussed in the Class note, there are several ways to alter asphalt concrete (AC)’s moisture susceptibility to water damage. Describe how to improve moisture susceptibility resistance of AC in terms of AC components. (5 marks)

• Increase asphalt content

• Higher viscosity asphalt

• Clean aggregate of dust and clay

• Change aggregate gradation

• Add anti-stripping additives

• liquid

• portland cement or lime

24. What are the various grades [systems] of asphalt cement? (4 marks)

• Penetration Grading (PEN)

• Viscosity Grading (AC)

• Aged Residue Grading (AR)

• Performance Grading (PG)

25. Based on the data in Table 2, determine the design binder content for a Superpave mix design for a 15 million ESAL. Assume a 12.5 mm nominal maximum aggregate size. Use an Excel sheet and submit the file. (20 marks)

Table 2. Design Binder Content

Data	Binder Content (%)
	5.5	6.0	6.5	7.0
Gmb	2.351	2.441	2.455	2.469
Gmm	2.579	2.558	2.538	2.518
Gb	1.025	1.025	1.025	1.025
Ps	94.5	94.0	93.5	93.0
Pd	4.5	4.5	4.5	4.5
Gsb	2.705	2.705	2.705	2.705
hini	129	131	131	128
hdes	112	113	116	115

26. Component diagram of asphalt concrete and the relevant equations are shown below. Find the following volumetric parameters (specify the UNITs): (2x13 = 26 points) In order to get full mark, show all your work.

W = V × G × γ_w where, γ_w = 1.0 g/cm³