Concrete & Masonry Construction Flashcards
7 cards from real FCC practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Concrete & Masonry Construction flashcards as text
What is the minimum lap splice length for a #5 deformed rebar in a tension zone when f'c = 3,000 psi, per ACI 318?
Answer: 30 inches
A Class A tension lap splice for a #5 bar in 3,000 psi concrete typically requires approximately 30 inches to fully develop the bar's tensile capacity.
According to ASTM C94, ready-mixed concrete must be discharged within how many minutes or revolutions of the drum after the introduction of water?
Answer: 90 minutes or 300 revolutions
ASTM C94 requires that ready-mixed concrete be discharged before 90 minutes or 300 drum revolutions have elapsed to prevent excessive hydration and loss of workability.
In Florida masonry construction, which mortar type is most commonly used for load-bearing exterior walls?
Answer: Type S
Type S mortar has high compressive and tensile bond strength, making it the preferred choice for load-bearing exterior masonry walls and walls in contact with the ground.
What test is performed on fresh concrete to determine its consistency and workability on a job site?
Answer: Slump test
The slump test (ASTM C143) measures the consistency and workability of fresh concrete by determining how much a standard cone of concrete settles after the mold is removed.
When vibrating freshly placed concrete, the vibrator should be inserted at intervals not exceeding how far apart to ensure proper consolidation?
Answer: 18 inches
Vibrators should be inserted at intervals not exceeding 1.5 times the vibrator's radius of action, which typically results in maximum 18-inch spacing for standard internal vibrators.
Which condition most commonly causes map cracking (crazing) on a concrete slab surface in Florida's hot climate?
Answer: Rapid surface drying before finishing
Crazing or map cracking is caused by rapid drying and shrinkage of the concrete surface before the interior has set, which is exacerbated by Florida's heat and low humidity.
Per the Florida Building Code, what is the minimum specified grout strength for masonry construction using running-bond CMU?
Answer: 2,500 psi
The Florida Building Code requires masonry grout to have a minimum compressive strength of 2,000 psi at 28 days when tested per ASTM C1019.