娇妻借朋友高h繁交h,公交车伦流澡到高潮hnp,六月婷婷网视频在线观看,天堂√最新版中文在线

Structural design knowledge: What are the advantages and disadvantages of steel structures?

Structural design knowledge: What are the advantages and disadvantages of steel structures?

What are the advantages and disadvantages of steel structures?
Steel features:
(1) high intensity, high weight ratio; good ductility, toughness;
(2) Material uniform, consistent mechanics assumptions, security high reliability;
(3) industrial production, a high degree of industrialization, the construction speed;
Cons: not fire-resistant steel heat; easy to rust, corrosion resistance is poor.