DM G+1 EXAM | 157 QUESTIONS | WITH ACTUAL SOLUTIONS 2026!!!/NEWEST UPDATE
Question 1
The shutters and bottom support of a non-cantilever slab can be removed within a minimum of
how many days?
A) 3 days
B) 7 days
C) 10 days
D) 14 days
E) 21 days
Correct Answer: D) 14 days
Rationale: For standard non-cantilever slabs, the concrete needs sufficient time to gain
roughly 70-80% of its characteristic strength to support its own weight and any
construction loads. While vertical formwork can be removed earlier, the soffit (bottom)
supports must remain for at least 14 days under standard conditions.
Question 2
Shotcrete is primarily used in which of the following construction scenarios?
A) Repairing damaged concrete surfaces
B) Sealing dam surfaces or reservoirs
C) Constructing curved or irregular surfaces
D) Stabilizing soil in excavations
E) All of the above
Correct Answer: E) All of the above
Rationale: Shotcrete is a method of applying concrete projected at high velocity onto a
surface. Because it does not require traditional formwork and provides excellent adhesion,
it is ideal for repairs, curved architecture, tunneling, and waterproofing dam faces.
Question 3
The shutters and bottom support of a non-cantilever beam should be removed within a minimum
of how many days?
A) 7 days
B) 10 days
C) 14 days
D) 21 days
E) 28 days
Correct Answer: C) 14 days
Rationale: Beams, like slabs, are flexural members. For spans up to 4.5 meters, 14 days is
the standard minimum for removing bottom props. For spans exceeding 4.5 meters, props
are often kept until 21 days, but the standard exam answer for G+1 residential beams is 14
days.
, 2
Question 4
In building construction, bitumen is applied to surfaces primarily to provide:
A) Structural reinforcement
B) A decorative finish
C) A protective waterproof surface
D) Increased compressive strength
E) Improved fire resistance
Correct Answer: C) A protective waterproof surface
Rationale: Bitumen is a hydrocarbon-based substance known for its water-repellent
properties. It is extensively used in foundations (tanking) and roofs to prevent moisture
ingress and protect the concrete from chemical attacks in the soil.
Question 5
The first formal strength test on concrete cubes is typically conducted after how many days of
curing?
A) 3 days
B) 7 days
C) 14 days
D) 21 days
E) 28 days
Correct Answer: B) 7 days
Rationale: Concrete is tested at 7 days to provide an early indication of its potential 28-day
strength. Usually, concrete should reach approximately 65-70% of its design strength by
the 7th day.
Question 6
What is the primary reason for taking concrete core samples from a structure?
A) To determine the water-cement ratio
B) To check the surface hardness only
C) To find the actual in-situ compressive strength
D) To measure the thickness of the reinforcement
E) To identify the type of cement used
Correct Answer: C) To find the actual in-situ compressive strength
Rationale: Core samples are a "destructive" test used when standard cube test results are
suspected of being inaccurate or when cubes fail to meet the required strength. It provides
the most accurate measurement of the concrete's strength as it exists in the actual
structural member.
Question 7
The Rebound Schmidt Hammer test is classified as which type of test?
A) Destructive test
, 3
B) Non-destructive test (NDT)
C) Chemical analysis test
D) Permeability test
E) Tension test
Correct Answer: B) Non-destructive test (NDT)
Rationale: The Schmidt Hammer measures the surface hardness of concrete by recording
the rebound of a spring-loaded mass. It does not damage the structure, making it a "non-
destructive" method to estimate compressive strength and uniformity.
Question 8
If core samples are required to verify concrete strength, they are typically taken after the concrete
has cured for at least:
A) 7 days
B) 14 days
C) 21 days
D) 28 days
E) 56 days
Correct Answer: D) 28 days
Rationale: 28 days is the benchmark age for concrete design strength (fc'). Testing cores at
this age allows for a direct comparison with the design specifications and the initial cube
test results.
Question 9
What is the approximate density of Aluminum at normal temperatures?
A) 1200 Kg/m³
B) 2500 Kg/m³
C) 2700 Kg/m³
D) 7800 Kg/m³
E) 8500 Kg/m³
Correct Answer: C) 2700 Kg/m³
Rationale: Aluminum is a lightweight metal with a density of approximately 2700 Kg/m³.
This is significantly lower than steel, which is around 7800-7850 Kg/m³.
Question 10
Which type of cement is most commonly used for casting normal residential slabs?
A) Sulfate Resisting Cement (SRC)
B) High Alumina Cement
C) Rapid Hardening Cement
D) Ordinary Portland Cement (OPC)
E) White Cement
Correct Answer: D) Ordinary Portland Cement (OPC)
, 4
Rationale: OPC (ASTM Type I) is the standard cement for general construction where there
is no significant risk of sulfate attack from soil or groundwater, such as in suspended slabs
and superstructures.
Question 11
The standard density of structural steel used in engineering calculations is:
A) 2400 Kg/m³
B) 5500 Kg/m³
C) 7200 Kg/m³
D) 7800 Kg/m³
E) 10000 Kg/m³
Correct Answer: D) 7800 Kg/m³
Rationale: Engineering standards (like BS and ACI) use 7800 to 7850 Kg/m³ as the standard
density for steel. This is essential for calculating the "Dead Load" of reinforcement and
steel structures.
Question 12
Why do contractors place wet blankets or plastic sheets over fresh concrete?
A) To speed up the setting time
B) To reduce water evaporation (curing)
C) To increase the concrete temperature
D) To prevent insects from landing on it
E) To hide the surface finish
Correct Answer: B) Reduce evaporation
Rationale: Curing is the process of maintaining moisture in concrete to ensure proper
hydration. Covering fresh concrete reduces the loss of mixing water due to sun and wind,
preventing shrinkage cracks and ensuring strength gain.
Question 13
The density of lightweight concrete, used for screeds or insulation, is approximately:
A) 500 Kg/m³
B) 1300 Kg/m³
C) 2400 Kg/m³
D) 3000 Kg/m³
E) 1000 Kg/m³
Correct Answer: B) 1300 Kg/m³
Rationale: Lightweight concrete typically ranges from 300 to 1800 Kg/m³ depending on the
aggregate. 1300 Kg/m³ is a common standard used in G+1 exams to distinguish it from
normal-weight concrete (~2400 Kg/m³).
Question 1
The shutters and bottom support of a non-cantilever slab can be removed within a minimum of
how many days?
A) 3 days
B) 7 days
C) 10 days
D) 14 days
E) 21 days
Correct Answer: D) 14 days
Rationale: For standard non-cantilever slabs, the concrete needs sufficient time to gain
roughly 70-80% of its characteristic strength to support its own weight and any
construction loads. While vertical formwork can be removed earlier, the soffit (bottom)
supports must remain for at least 14 days under standard conditions.
Question 2
Shotcrete is primarily used in which of the following construction scenarios?
A) Repairing damaged concrete surfaces
B) Sealing dam surfaces or reservoirs
C) Constructing curved or irregular surfaces
D) Stabilizing soil in excavations
E) All of the above
Correct Answer: E) All of the above
Rationale: Shotcrete is a method of applying concrete projected at high velocity onto a
surface. Because it does not require traditional formwork and provides excellent adhesion,
it is ideal for repairs, curved architecture, tunneling, and waterproofing dam faces.
Question 3
The shutters and bottom support of a non-cantilever beam should be removed within a minimum
of how many days?
A) 7 days
B) 10 days
C) 14 days
D) 21 days
E) 28 days
Correct Answer: C) 14 days
Rationale: Beams, like slabs, are flexural members. For spans up to 4.5 meters, 14 days is
the standard minimum for removing bottom props. For spans exceeding 4.5 meters, props
are often kept until 21 days, but the standard exam answer for G+1 residential beams is 14
days.
, 2
Question 4
In building construction, bitumen is applied to surfaces primarily to provide:
A) Structural reinforcement
B) A decorative finish
C) A protective waterproof surface
D) Increased compressive strength
E) Improved fire resistance
Correct Answer: C) A protective waterproof surface
Rationale: Bitumen is a hydrocarbon-based substance known for its water-repellent
properties. It is extensively used in foundations (tanking) and roofs to prevent moisture
ingress and protect the concrete from chemical attacks in the soil.
Question 5
The first formal strength test on concrete cubes is typically conducted after how many days of
curing?
A) 3 days
B) 7 days
C) 14 days
D) 21 days
E) 28 days
Correct Answer: B) 7 days
Rationale: Concrete is tested at 7 days to provide an early indication of its potential 28-day
strength. Usually, concrete should reach approximately 65-70% of its design strength by
the 7th day.
Question 6
What is the primary reason for taking concrete core samples from a structure?
A) To determine the water-cement ratio
B) To check the surface hardness only
C) To find the actual in-situ compressive strength
D) To measure the thickness of the reinforcement
E) To identify the type of cement used
Correct Answer: C) To find the actual in-situ compressive strength
Rationale: Core samples are a "destructive" test used when standard cube test results are
suspected of being inaccurate or when cubes fail to meet the required strength. It provides
the most accurate measurement of the concrete's strength as it exists in the actual
structural member.
Question 7
The Rebound Schmidt Hammer test is classified as which type of test?
A) Destructive test
, 3
B) Non-destructive test (NDT)
C) Chemical analysis test
D) Permeability test
E) Tension test
Correct Answer: B) Non-destructive test (NDT)
Rationale: The Schmidt Hammer measures the surface hardness of concrete by recording
the rebound of a spring-loaded mass. It does not damage the structure, making it a "non-
destructive" method to estimate compressive strength and uniformity.
Question 8
If core samples are required to verify concrete strength, they are typically taken after the concrete
has cured for at least:
A) 7 days
B) 14 days
C) 21 days
D) 28 days
E) 56 days
Correct Answer: D) 28 days
Rationale: 28 days is the benchmark age for concrete design strength (fc'). Testing cores at
this age allows for a direct comparison with the design specifications and the initial cube
test results.
Question 9
What is the approximate density of Aluminum at normal temperatures?
A) 1200 Kg/m³
B) 2500 Kg/m³
C) 2700 Kg/m³
D) 7800 Kg/m³
E) 8500 Kg/m³
Correct Answer: C) 2700 Kg/m³
Rationale: Aluminum is a lightweight metal with a density of approximately 2700 Kg/m³.
This is significantly lower than steel, which is around 7800-7850 Kg/m³.
Question 10
Which type of cement is most commonly used for casting normal residential slabs?
A) Sulfate Resisting Cement (SRC)
B) High Alumina Cement
C) Rapid Hardening Cement
D) Ordinary Portland Cement (OPC)
E) White Cement
Correct Answer: D) Ordinary Portland Cement (OPC)
, 4
Rationale: OPC (ASTM Type I) is the standard cement for general construction where there
is no significant risk of sulfate attack from soil or groundwater, such as in suspended slabs
and superstructures.
Question 11
The standard density of structural steel used in engineering calculations is:
A) 2400 Kg/m³
B) 5500 Kg/m³
C) 7200 Kg/m³
D) 7800 Kg/m³
E) 10000 Kg/m³
Correct Answer: D) 7800 Kg/m³
Rationale: Engineering standards (like BS and ACI) use 7800 to 7850 Kg/m³ as the standard
density for steel. This is essential for calculating the "Dead Load" of reinforcement and
steel structures.
Question 12
Why do contractors place wet blankets or plastic sheets over fresh concrete?
A) To speed up the setting time
B) To reduce water evaporation (curing)
C) To increase the concrete temperature
D) To prevent insects from landing on it
E) To hide the surface finish
Correct Answer: B) Reduce evaporation
Rationale: Curing is the process of maintaining moisture in concrete to ensure proper
hydration. Covering fresh concrete reduces the loss of mixing water due to sun and wind,
preventing shrinkage cracks and ensuring strength gain.
Question 13
The density of lightweight concrete, used for screeds or insulation, is approximately:
A) 500 Kg/m³
B) 1300 Kg/m³
C) 2400 Kg/m³
D) 3000 Kg/m³
E) 1000 Kg/m³
Correct Answer: B) 1300 Kg/m³
Rationale: Lightweight concrete typically ranges from 300 to 1800 Kg/m³ depending on the
aggregate. 1300 Kg/m³ is a common standard used in G+1 exams to distinguish it from
normal-weight concrete (~2400 Kg/m³).
