Concrete Construction Inspection Flashcards
6 cards from real ACI Certification practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Concrete Construction Inspection flashcards as text
During pre-pour inspection of formwork, what critical dimension must the inspector verify to ensure structural integrity of the formed element?
Answer: Form dimensions match the structural drawings within specified tolerances
The inspector must verify that form dimensions — width, depth, length, and location — match the structural drawings within ACI 117 tolerances; dimensional errors affect structural capacity and rebar cover.
What is the primary purpose of a pre-concrete placement inspection checklist for a reinforced concrete slab?
Answer: To verify that all reinforcement, embedments, and form conditions are correct before concrete is ordered
A pre-placement inspection ensures all conditions — rebar size, spacing, lap splices, cover, dowels, blockouts, and form integrity — are correct before concrete is irreversibly placed.
According to ACI 318, what is the minimum required compressive strength (f'c) for concrete exposed to deicing chemicals?
Answer: 4,500 psi (31 MPa)
ACI 318 Table 19.3.3.1 requires a minimum f'c of 4,500 psi (31 MPa) for concrete in contact with deicing chemicals, to provide adequate durability against freeze-thaw and chemical attack.
When sampling fresh concrete for test cylinders per ASTM C172, how many increments must be taken, and what portion of the load is excluded from sampling?
Answer: At least three increments; the first and last 10% of the load are excluded
ASTM C172 requires at least three increments sampled at regularly spaced intervals during the middle portion of the discharge, excluding the first and last 10% to avoid segregated concrete at the extremes.
What action should an inspector take when a set of concrete test cylinders from a critical structural element fails to meet specified compressive strength at 28 days?
Answer: Notify the engineer of record and follow the provisions of ACI 318 Section 26.12 for evaluating the structural adequacy of the in-place concrete
ACI 318 Section 26.12 provides a structured process: investigate causes, consider testing cores, and evaluate structural adequacy before deciding on remediation or demolition.
What is the maximum water-cementitious material ratio (w/cm) permitted by ACI 318 for concrete exposed to freezing and thawing in a moist condition or to deicing chemicals (Exposure Class F2)?
Answer: 0.45
ACI 318 Table 19.3.3.1 specifies a maximum w/cm of 0.45 for Exposure Class F2 to limit permeability and enhance freeze-thaw resistance.