Core TradesCâu 122 / 700
What is the MINIMUM concrete cover required to protect reinforcing steel in concrete that is cast against and permanently exposed to earth?
a.3/4 inch
b.1-1/2 inches
c.2 inches
d.3 inches
Giải thích
Concrete cast directly against earth requires 3 inches of cover because the rough soil interface offers the least protection against moisture and corrosion. 1-1/2 inches applies to formed surfaces exposed to weather (smaller bars), 2 inches to larger formed bars exposed to weather, and 3/4 inch to interior surfaces not exposed to weather or ground.
Trích dẫn luật: 2025 CA Building Code, Chapter 19 (per ACI 318 §20.5.1)Luyện miễn phí toàn bộ 700 câu hỏi — không cần đăng ký.
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