CPII Construction Inspection Techniques 3 — Questions and Answers
Question 1: When performing a visual weld inspection, a linear discontinuity running parallel to the weld axis on the weld face is most likely which type of defect?
- Porosity
- Undercut
- Longitudinal crack (Correct answer)
- Overlap
Correct answer: Longitudinal crack
A linear discontinuity running parallel to the weld axis on the weld face is characteristic of a longitudinal crack, which is a serious structural defect requiring rejection and repair.
Question 2: An inspector is reviewing shop drawings for a precast concrete structure. What is the primary purpose of reviewing shop drawings during construction inspection?
- To redesign structural elements for cost savings
- To verify that the contractor's proposed fabrication details conform to the contract documents (Correct answer)
- To approve changes to the original design engineer's specifications
- To establish a new project schedule based on fabricator capabilities
Correct answer: To verify that the contractor's proposed fabrication details conform to the contract documents
Shop drawing review confirms that the contractor's interpretation and fabrication details comply with the engineer's design intent as expressed in the contract documents.
Question 3: Which ASTM standard governs the standard practice for sampling freshly mixed concrete?
- ASTM C172 (Correct answer)
- ASTM C31
- ASTM C143
- ASTM C39
Correct answer: ASTM C172
ASTM C172 covers the standard practice for sampling freshly mixed concrete to obtain representative samples for testing of properties such as slump, air content, and temperature.
Question 4: During earthwork inspection, a nuclear density gauge shows 91% relative compaction where 95% is specified. What action is required?
- Accept the work since 91% is within a reasonable tolerance
- Require the contractor to re-compact the failing area and retest until specification is met (Correct answer)
- Average the result with adjacent passing tests to qualify the area
- Proceed with work and address compaction at the final inspection
Correct answer: Require the contractor to re-compact the failing area and retest until specification is met
Failing compaction tests require the contractor to re-compact the deficient area and perform additional testing until the specified density is achieved before proceeding.
Question 5: What is the purpose of performing an air content test on fresh concrete intended for an exposed exterior application in a freeze-thaw environment?
- To reduce the water-cement ratio for higher strength
- To verify that adequate entrained air is present to resist freeze-thaw deterioration (Correct answer)
- To increase workability for easier placement
- To confirm aggregate size meets gradation requirements
Correct answer: To verify that adequate entrained air is present to resist freeze-thaw deterioration
Entrained air creates microscopic bubbles that relieve hydraulic pressure from freezing water, protecting the concrete matrix from freeze-thaw deterioration and scaling.
Question 6: When inspecting the installation of a steel H-pile, the inspector notices the driving log shows a sudden drop in blow counts (easier driving) at depth. What does this most likely indicate?
- The pile has reached the required bearing capacity
- The pile tip may have encountered a soft layer or void (Correct answer)
- The hammer energy has increased to an appropriate level
- The pile set is within acceptable specification limits
Correct answer: The pile tip may have encountered a soft layer or void
A sudden decrease in blow count during driving typically indicates the pile tip has entered a soft soil layer or void, which may compromise bearing capacity and require further evaluation.
Question 7: Which document serves as the official record of all field observations, test results, contractor activities, and weather conditions maintained by the inspector?
- Request for Information (RFI)
- Daily Field Report (Inspector's Daily Report) (Correct answer)
- Submittal log
- Notice to Proceed
Correct answer: Daily Field Report (Inspector's Daily Report)
The Daily Field Report is the inspector's official contemporaneous record of site activities, test results, conditions, and observations that serves as a legal construction record.
CPII Construction Inspection Techniques 3
When performing a visual weld inspection, a linear discontinuity running parallel to the weld axis on the weld face is most likely which type of defect?