EGB273 Exam ACTUAL QUESTIONS AND
CORRECT ANSWERS
What is a Mass Haul diagram used for - CORRECT ANSWER Profile of road may be
different from profile of site, hence excavation/embankment may be needed, provides quick
and quantitive information about cut and fill volumes and movements
What is Haul - CORRECT ANSWER Haul is movement of earth materials from the
excavation site to a location
What are the two types of pavements and explain them - CORRECT
ANSWER Flexible: unbound/granular/stabilised materials/ ashpalt
Rigid: concrete pavements with joints/steel reinforcement, high strengtn concrete (30Mpa+)
What is subgrade - CORRECT ANSWER Strength of subgrae determines thicknes of
pavement and strength (CBR)
Explain CBR ratio - CORRECT ANSWER - ratio of test load to the standard load at a
specified penetration by a standard plunger under controlled density and moisture conditions
(mix with water at optimum water content, then compact with 3 layers, then apply pressure)
- The test is performed by measuring the pressure required to penetrate a soil sample with a
plunger of standard area
- The measured pressure is then divided by the pressure required to achieve an equal
penetration on a standard crushed rock material, using the values obtained from the test from
an empirical design chart, the pavement thickness is calculated
What is a foundation - CORRECT ANSWER - A foundation is an element of structure
in direct contact with the ground, and which transmits the load of the structure to the ground
What are the functions of a foundation - CORRECT ANSWER o Support for the
superstructures
o Prevent settlement
, o Prevent possible movement of structure due to periodic shrinkage and swelling of subsoil
o Allow building over water or water-logged ground
o Resist uplift or overturning forces due to wind
o Resist lateral forces due to soil movement
o Underpin existing or unstable structures
Reasons of selection foundations - CORRECT ANSWER o Nature of sub-soil
o Materials used for the foundation
o Economical consideration
o Construction program
o Layout of structure
o Site constraints
o Local availability of plant and equipment
o Acceptable settlement
What are the two types of foundation and briefly explain their functions - CORRECT
ANSWER Shallow (pad) - lighter than deap, cheaper, no specialist equipment, used ofr
loght loads or good ground conditions, ot good when ground conditions vvary across site
Deep (piled) -long slender columns driven into ground, used for high-rise buldings, bridges
or structures on weak soils, provides stability where shallow foundations would fail
Types of shallow pad foundation - CORRECT ANSWER Strip footing, Pad (or Spread)
footing,Raft (or Mat) footing, Strapped (orCombined) footing
Types of deep piled foundation (driven pile) - CORRECT ANSWER Timber: low cost,
renewable supply, lng history of success
H-section: expensive, higher load carrying capacity, high resistance to driving, prone to
corrosion
Precast concrete: conventionally reinforced, higher strength when prestresed, noisy,
vibrations can impact other buildings
CORRECT ANSWERS
What is a Mass Haul diagram used for - CORRECT ANSWER Profile of road may be
different from profile of site, hence excavation/embankment may be needed, provides quick
and quantitive information about cut and fill volumes and movements
What is Haul - CORRECT ANSWER Haul is movement of earth materials from the
excavation site to a location
What are the two types of pavements and explain them - CORRECT
ANSWER Flexible: unbound/granular/stabilised materials/ ashpalt
Rigid: concrete pavements with joints/steel reinforcement, high strengtn concrete (30Mpa+)
What is subgrade - CORRECT ANSWER Strength of subgrae determines thicknes of
pavement and strength (CBR)
Explain CBR ratio - CORRECT ANSWER - ratio of test load to the standard load at a
specified penetration by a standard plunger under controlled density and moisture conditions
(mix with water at optimum water content, then compact with 3 layers, then apply pressure)
- The test is performed by measuring the pressure required to penetrate a soil sample with a
plunger of standard area
- The measured pressure is then divided by the pressure required to achieve an equal
penetration on a standard crushed rock material, using the values obtained from the test from
an empirical design chart, the pavement thickness is calculated
What is a foundation - CORRECT ANSWER - A foundation is an element of structure
in direct contact with the ground, and which transmits the load of the structure to the ground
What are the functions of a foundation - CORRECT ANSWER o Support for the
superstructures
o Prevent settlement
, o Prevent possible movement of structure due to periodic shrinkage and swelling of subsoil
o Allow building over water or water-logged ground
o Resist uplift or overturning forces due to wind
o Resist lateral forces due to soil movement
o Underpin existing or unstable structures
Reasons of selection foundations - CORRECT ANSWER o Nature of sub-soil
o Materials used for the foundation
o Economical consideration
o Construction program
o Layout of structure
o Site constraints
o Local availability of plant and equipment
o Acceptable settlement
What are the two types of foundation and briefly explain their functions - CORRECT
ANSWER Shallow (pad) - lighter than deap, cheaper, no specialist equipment, used ofr
loght loads or good ground conditions, ot good when ground conditions vvary across site
Deep (piled) -long slender columns driven into ground, used for high-rise buldings, bridges
or structures on weak soils, provides stability where shallow foundations would fail
Types of shallow pad foundation - CORRECT ANSWER Strip footing, Pad (or Spread)
footing,Raft (or Mat) footing, Strapped (orCombined) footing
Types of deep piled foundation (driven pile) - CORRECT ANSWER Timber: low cost,
renewable supply, lng history of success
H-section: expensive, higher load carrying capacity, high resistance to driving, prone to
corrosion
Precast concrete: conventionally reinforced, higher strength when prestresed, noisy,
vibrations can impact other buildings
