Before back-propping/loading a young slab, the most common shoring/loading safeguard threshold is (generic practice):
Choices
- (A) 24 hours
- (B) 75% of 28-d f꜀′ on day 0
- (C) Reach ~50% of 28-d strength (often ~7d) or project rule
- (D) Rely on dead load estimate only
Correct answer: (C)
Reach ~50% of 28-d strength (often ~7d) or project rule
Explanation
Reshore/shoring release rules site-specific; many specs target ~50% f꜀′ (often ~7d) or similar.