CM2112 EXAM 1 QUESTIONS WITH VERIFIED
ANSWERS
During the slump flow test (ASTM C1611) the stability (segregation resistance) of SCC
can also be evaluated by visual inspection. - Answers - True
Flexural strength of plain concrete is usually around .... of its compressive strength,
while tensile strength is only about .... of its compressive strength. - Answers - 15%-
10%
In normal conditions, the hydration reactions during the first 0.5 hour (after the initial
water-cement contact) are not significant, and the resulting slump loss is negligible. -
Answers - True
Plastic shrinkage cracking occurs when water evaporates from the surface of fresh
concrete faster than it can travel to the surface during the bleeding process. - Answers -
True
Portland cement production is an energy-intensive AND carbon-intensive process. -
Answers - True
SCC formwork pressure is lower than conventional concrete, due to its workability. -
Answers - False
The chemical reactions between Portland cement and water are called: - Answers -
Hydration reactions
The main disadvantages of concrete as a construction material include all of the
followings, EXCEPT: - Answers - flammability
This is the most universally used measure for concrete quality: - Answers - compressive
strength
Traditional specifications and tests for concrete strength are based on ... - Answers -
Specimens cured under standard temperature-humidity conditions for 28 days
Two types of concrete pumps are piston pumps and peristaltic pumps. In the piston
pumps, the concrete in the hopper is fed into the pump by gravity aided by suction,
while in peristaltic pumps, the concrete is fed by rotating blades in the hopper. -
Answers - True
, Type IV (four) Portland cement is... - Answers - A special cement with a low heat of
hydration
When designing a concrete mixture, a higher W/CM ratio leads to higher shrinkage and
mechanical strength. - Answers - False
Which of the following statements on concrete proportions and properties is NOT
accurate? - Answers - The more aggregate used, the higher the cost of the concrete.
Which of the following statements on concrete workability is correct? - Answers -
Consistency is a close indication of workability.
Which of the following statements on fiber reinforced concrete (FRC) is NOT accurate?
- Answers - FRC specimens usually break immediately after initiation of the first crack
Which of the following statements on plastic shrinkage is NOT accurate? - Answers -
Plastic shrinkage is just another term for "drying shrinkage"
Which of the following statements on Portland cement and concrete is NOT accurate? -
Answers - Concrete structures are commonly recycled and reused at the end of their
service life
Wood as a construction material is known to have all of the following properties,
EXCEPT: - Answers - No shrinkage and swelling
Workability of SCC is described in terms of: - Answers - Stability, passing ability, and
filling ability
... is the main hydration product which is stable and helps the concrete gain mechanical
strength over time, while calcium hydroxide is not an ideal hydration product (water
soluble). - Answers - Calcium Silicate Hydrate (C-S-H)
A better mixture homogeneity can be achieved by using twin-shaft mixers, due to the
high degree of turbulence developed in the intersection zone of the two mixing circles. -
Answers - True
All of the followings are advantages of using Fly Ash as an SCM, EXCEPT: - Answers -
Faster hydration
Cements that not only harden by reacting with water, but also form a water-resistant
product are called: - Answers - Hydraulic cement
During Portland cement production, approximately 8% gypsum is added to clinker
(during grinding) to control early setting and hardening of cement. - Answers - False
ANSWERS
During the slump flow test (ASTM C1611) the stability (segregation resistance) of SCC
can also be evaluated by visual inspection. - Answers - True
Flexural strength of plain concrete is usually around .... of its compressive strength,
while tensile strength is only about .... of its compressive strength. - Answers - 15%-
10%
In normal conditions, the hydration reactions during the first 0.5 hour (after the initial
water-cement contact) are not significant, and the resulting slump loss is negligible. -
Answers - True
Plastic shrinkage cracking occurs when water evaporates from the surface of fresh
concrete faster than it can travel to the surface during the bleeding process. - Answers -
True
Portland cement production is an energy-intensive AND carbon-intensive process. -
Answers - True
SCC formwork pressure is lower than conventional concrete, due to its workability. -
Answers - False
The chemical reactions between Portland cement and water are called: - Answers -
Hydration reactions
The main disadvantages of concrete as a construction material include all of the
followings, EXCEPT: - Answers - flammability
This is the most universally used measure for concrete quality: - Answers - compressive
strength
Traditional specifications and tests for concrete strength are based on ... - Answers -
Specimens cured under standard temperature-humidity conditions for 28 days
Two types of concrete pumps are piston pumps and peristaltic pumps. In the piston
pumps, the concrete in the hopper is fed into the pump by gravity aided by suction,
while in peristaltic pumps, the concrete is fed by rotating blades in the hopper. -
Answers - True
, Type IV (four) Portland cement is... - Answers - A special cement with a low heat of
hydration
When designing a concrete mixture, a higher W/CM ratio leads to higher shrinkage and
mechanical strength. - Answers - False
Which of the following statements on concrete proportions and properties is NOT
accurate? - Answers - The more aggregate used, the higher the cost of the concrete.
Which of the following statements on concrete workability is correct? - Answers -
Consistency is a close indication of workability.
Which of the following statements on fiber reinforced concrete (FRC) is NOT accurate?
- Answers - FRC specimens usually break immediately after initiation of the first crack
Which of the following statements on plastic shrinkage is NOT accurate? - Answers -
Plastic shrinkage is just another term for "drying shrinkage"
Which of the following statements on Portland cement and concrete is NOT accurate? -
Answers - Concrete structures are commonly recycled and reused at the end of their
service life
Wood as a construction material is known to have all of the following properties,
EXCEPT: - Answers - No shrinkage and swelling
Workability of SCC is described in terms of: - Answers - Stability, passing ability, and
filling ability
... is the main hydration product which is stable and helps the concrete gain mechanical
strength over time, while calcium hydroxide is not an ideal hydration product (water
soluble). - Answers - Calcium Silicate Hydrate (C-S-H)
A better mixture homogeneity can be achieved by using twin-shaft mixers, due to the
high degree of turbulence developed in the intersection zone of the two mixing circles. -
Answers - True
All of the followings are advantages of using Fly Ash as an SCM, EXCEPT: - Answers -
Faster hydration
Cements that not only harden by reacting with water, but also form a water-resistant
product are called: - Answers - Hydraulic cement
During Portland cement production, approximately 8% gypsum is added to clinker
(during grinding) to control early setting and hardening of cement. - Answers - False
