ICC Post-Tensioned Concrete Special
Inspector Examination Questions And
Correct Answers (Verified Answers) Plus
Rationales 2026 Q&A | Instant
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Question 1
What is the minimum required concrete compressive strength at the time of post-
tensioning, unless otherwise specified by the engineer of record?
A. 2,500 psi
B. 3,000 psi
C. 3,500 psi
D. 4,000 psi
Answer: B. 3,000 psi
Rationale: The ICC Post-Tensioned Concrete Special Inspector Examination
references the requirements that post-tensioning shall not be applied until the
concrete has attained a minimum compressive strength of 3,000 psi, unless the
licensed design professional specifies a different value. This ensures the concrete
can adequately resist the forces imposed during tensioning without cracking or
excessive deformation.
Question 2
Which of the following is the maximum allowable chloride ion content in
prestressed concrete by weight of cement?
A. 0.06%
B. 0.10%
,C. 0.15%
D. 0.20%
Answer: A. 0.06%
Rationale: For prestressed concrete, the maximum water-soluble chloride ion
content is strictly limited to 0.06% by weight of cement to prevent corrosion of
the high-strength steel strands. This limit is more stringent than for reinforced
concrete due to the higher stress levels and susceptibility to stress corrosion
cracking in prestressing tendons.
Question 3
What is the primary purpose of the stressing end anchorage in a post-tensioned
system?
A. To guide the tendon during installation
B. To transfer the prestressing force to the concrete
C. To protect the tendon from corrosion
D. To allow for tendon elongation measurement
Answer: B. To transfer the prestressing force to the concrete
Rationale: The stressing end anchorage is specifically designed to transfer the
prestressing force from the tendon to the concrete through bearing. The anchor
bears against the concrete at the end of the member, and the wedge system
locks the strand, maintaining the applied tension and transferring it into the
structural element.
Question 4
When inspecting grout for bonded post-tensioning, what is the maximum
allowable water-to-cementitious materials ratio?
A. 0.35
B. 0.40
C. 0.45
D. 0.50
,Answer: C. 0.45
Rationale: The maximum water-to-cementitious materials ratio for grout in
bonded post-tensioning is 0.45 by weight. This limit ensures adequate strength,
durability, and reduces bleeding and shrinkage. Lower water content also
minimizes the risk of voids and ensures complete encapsulation of the tendon for
corrosion protection.
Question 5
Which type of strand is most commonly used in post-tensioned concrete
construction?
A. 7-wire strand
B. 19-wire strand
C. Monostrand
D. Bar tendon
Answer: A. 7-wire strand
Rationale: The 7-wire strand, consisting of six outer wires helically wound
around a center wire, is the most common type used in post-tensioning. It
provides an excellent balance of strength, flexibility, and bond characteristics.
Monostrand refers to a single 7-wire strand within a duct, and bar tendons are
used less frequently for specialized applications.
Question 6
What is the minimum concrete cover requirement for post-tensioned tendons in
slabs cast against earth?
A. 1 inch
B. 1.5 inches
C. 2 inches
D. 3 inches
Answer: D. 3 inches
Rationale: According to building codes, tendons in post-tensioned slabs cast
, against earth require a minimum concrete cover of 3 inches to protect against
corrosion from ground moisture and chemicals. This increased cover is necessary
because the soil side is more susceptible to moisture intrusion and potential
contaminants.
Question 7
During the stressing operation, which of the following must be continuously
monitored?
A. Concrete temperature
B. Tendon elongation and jack pressure
C. Ambient humidity
D. Formwork vibration
Answer: B. Tendon elongation and jack pressure
Rationale: The inspector must continuously monitor both tendon elongation and
jack pressure (or hydraulic gauge readings) during stressing. These two
measurements provide the primary means of verifying that the applied force is
correct and that the tendon is behaving as expected. Discrepancies between
measured and calculated elongation indicate potential issues such as blockage,
friction, or anchor set.
Question 8
What is the typical minimum yield strength of Grade 270 prestressing strand?
A. 240 ksi
B. 250 ksi
C. 260 ksi
D. 270 ksi
Answer: D. 270 ksi
Rationale: Grade 270 prestressing strand has a specified minimum yield strength
of 270 ksi (1860 MPa). This high-strength steel is specifically manufactured for
Inspector Examination Questions And
Correct Answers (Verified Answers) Plus
Rationales 2026 Q&A | Instant
Download Pdf
Question 1
What is the minimum required concrete compressive strength at the time of post-
tensioning, unless otherwise specified by the engineer of record?
A. 2,500 psi
B. 3,000 psi
C. 3,500 psi
D. 4,000 psi
Answer: B. 3,000 psi
Rationale: The ICC Post-Tensioned Concrete Special Inspector Examination
references the requirements that post-tensioning shall not be applied until the
concrete has attained a minimum compressive strength of 3,000 psi, unless the
licensed design professional specifies a different value. This ensures the concrete
can adequately resist the forces imposed during tensioning without cracking or
excessive deformation.
Question 2
Which of the following is the maximum allowable chloride ion content in
prestressed concrete by weight of cement?
A. 0.06%
B. 0.10%
,C. 0.15%
D. 0.20%
Answer: A. 0.06%
Rationale: For prestressed concrete, the maximum water-soluble chloride ion
content is strictly limited to 0.06% by weight of cement to prevent corrosion of
the high-strength steel strands. This limit is more stringent than for reinforced
concrete due to the higher stress levels and susceptibility to stress corrosion
cracking in prestressing tendons.
Question 3
What is the primary purpose of the stressing end anchorage in a post-tensioned
system?
A. To guide the tendon during installation
B. To transfer the prestressing force to the concrete
C. To protect the tendon from corrosion
D. To allow for tendon elongation measurement
Answer: B. To transfer the prestressing force to the concrete
Rationale: The stressing end anchorage is specifically designed to transfer the
prestressing force from the tendon to the concrete through bearing. The anchor
bears against the concrete at the end of the member, and the wedge system
locks the strand, maintaining the applied tension and transferring it into the
structural element.
Question 4
When inspecting grout for bonded post-tensioning, what is the maximum
allowable water-to-cementitious materials ratio?
A. 0.35
B. 0.40
C. 0.45
D. 0.50
,Answer: C. 0.45
Rationale: The maximum water-to-cementitious materials ratio for grout in
bonded post-tensioning is 0.45 by weight. This limit ensures adequate strength,
durability, and reduces bleeding and shrinkage. Lower water content also
minimizes the risk of voids and ensures complete encapsulation of the tendon for
corrosion protection.
Question 5
Which type of strand is most commonly used in post-tensioned concrete
construction?
A. 7-wire strand
B. 19-wire strand
C. Monostrand
D. Bar tendon
Answer: A. 7-wire strand
Rationale: The 7-wire strand, consisting of six outer wires helically wound
around a center wire, is the most common type used in post-tensioning. It
provides an excellent balance of strength, flexibility, and bond characteristics.
Monostrand refers to a single 7-wire strand within a duct, and bar tendons are
used less frequently for specialized applications.
Question 6
What is the minimum concrete cover requirement for post-tensioned tendons in
slabs cast against earth?
A. 1 inch
B. 1.5 inches
C. 2 inches
D. 3 inches
Answer: D. 3 inches
Rationale: According to building codes, tendons in post-tensioned slabs cast
, against earth require a minimum concrete cover of 3 inches to protect against
corrosion from ground moisture and chemicals. This increased cover is necessary
because the soil side is more susceptible to moisture intrusion and potential
contaminants.
Question 7
During the stressing operation, which of the following must be continuously
monitored?
A. Concrete temperature
B. Tendon elongation and jack pressure
C. Ambient humidity
D. Formwork vibration
Answer: B. Tendon elongation and jack pressure
Rationale: The inspector must continuously monitor both tendon elongation and
jack pressure (or hydraulic gauge readings) during stressing. These two
measurements provide the primary means of verifying that the applied force is
correct and that the tendon is behaving as expected. Discrepancies between
measured and calculated elongation indicate potential issues such as blockage,
friction, or anchor set.
Question 8
What is the typical minimum yield strength of Grade 270 prestressing strand?
A. 240 ksi
B. 250 ksi
C. 260 ksi
D. 270 ksi
Answer: D. 270 ksi
Rationale: Grade 270 prestressing strand has a specified minimum yield strength
of 270 ksi (1860 MPa). This high-strength steel is specifically manufactured for
