EGB273 Final Exam UPDATED ACTUAL
QUESTIONS AND CORRECT ANSWERS
Phases Of Road Construction - CORRECT ANSWER -The earthworks (Cut and Fill &
preparation of soil)
-The construction of the pavement
Haul Distances For Mobile Systems - CORRECT ANSWER Dozer 150m
Wheel Loaders 200m
Scraper 3000m
Articulated Truck 4500m
Rear Dump Truck 9000m
Wagon 11000m
Other Kinds of Plant and Equipment - CORRECT ANSWER Water distributor, drill &
blast equipment, paving machines, bitumen sprayers & equipment, dewatering systems
Subgrade Strength - CORRECT ANSWER -Determines the thickness of the pavement
needed
-Can be achieved by 3 ways
-California Bearing Ration (C.B.R)
CBR for all soils except lean clays, sandy clay below 10 - CORRECT ANSWER CBR
= 292/(DPI^1.12)
CBR for soils with CBR less than 10 - CORRECT ANSWER CBR =
(1/(0.0170019*DPI)^2
CBR for fat clays soils - CORRECT ANSWER CBR = (1/(0.002871*DPI)
, Subgrade Strength - Good quality material, just rip and re-compact - CORRECT
ANSWER >15
Subgrade Strength - moderate quality, needs 150 mm of CBR>15 above - CORRECT
ANSWER 7 to 15
Subgrade strength - fair quality needs 150 mm of CBR>15 + 150mm of CBR>7 above -
CORRECT ANSWER 3 to 7
Subgrade Strength - poor material, special treatment - CORRECT ANSWER <3
Why do we need subsoil drainage? - CORRECT ANSWER Capillary action and
seepage
Soil Stabilisation - CORRECT ANSWER -Treatment of the soil that increases the
strength, means include cement or bitumen
Pavement Material - Flexible Pavement - CORRECT ANSWER Unbound granular or
stabilised materials or asphalt
Pavement Material - Rigid Pavement - CORRECT ANSWER -Concrete pavement with
joints or steel reinforcements
-Relatively high strength concrete (30)
-Range of subbase materials (lean mix concrete, cement stabilised crushed rock, unbound
granular materials)
What are contraction joints? - CORRECT ANSWER Control cracking in rigid
pavements from shrinkage, contraction, temperature and moisture changes.
They allow and control movements.
Dowel bars are used to transfer loads across the joints
QUESTIONS AND CORRECT ANSWERS
Phases Of Road Construction - CORRECT ANSWER -The earthworks (Cut and Fill &
preparation of soil)
-The construction of the pavement
Haul Distances For Mobile Systems - CORRECT ANSWER Dozer 150m
Wheel Loaders 200m
Scraper 3000m
Articulated Truck 4500m
Rear Dump Truck 9000m
Wagon 11000m
Other Kinds of Plant and Equipment - CORRECT ANSWER Water distributor, drill &
blast equipment, paving machines, bitumen sprayers & equipment, dewatering systems
Subgrade Strength - CORRECT ANSWER -Determines the thickness of the pavement
needed
-Can be achieved by 3 ways
-California Bearing Ration (C.B.R)
CBR for all soils except lean clays, sandy clay below 10 - CORRECT ANSWER CBR
= 292/(DPI^1.12)
CBR for soils with CBR less than 10 - CORRECT ANSWER CBR =
(1/(0.0170019*DPI)^2
CBR for fat clays soils - CORRECT ANSWER CBR = (1/(0.002871*DPI)
, Subgrade Strength - Good quality material, just rip and re-compact - CORRECT
ANSWER >15
Subgrade Strength - moderate quality, needs 150 mm of CBR>15 above - CORRECT
ANSWER 7 to 15
Subgrade strength - fair quality needs 150 mm of CBR>15 + 150mm of CBR>7 above -
CORRECT ANSWER 3 to 7
Subgrade Strength - poor material, special treatment - CORRECT ANSWER <3
Why do we need subsoil drainage? - CORRECT ANSWER Capillary action and
seepage
Soil Stabilisation - CORRECT ANSWER -Treatment of the soil that increases the
strength, means include cement or bitumen
Pavement Material - Flexible Pavement - CORRECT ANSWER Unbound granular or
stabilised materials or asphalt
Pavement Material - Rigid Pavement - CORRECT ANSWER -Concrete pavement with
joints or steel reinforcements
-Relatively high strength concrete (30)
-Range of subbase materials (lean mix concrete, cement stabilised crushed rock, unbound
granular materials)
What are contraction joints? - CORRECT ANSWER Control cracking in rigid
pavements from shrinkage, contraction, temperature and moisture changes.
They allow and control movements.
Dowel bars are used to transfer loads across the joints
