Steel bar is a common building material, among which threaded steel is more commonly used in the building. Its scientific name is called cold-rolled ribbed steel. It is a bar that rolls round steel on the cold rolling mill and passes the cold roller to form a regular section shape, which can improve its strength and adhesion with concrete.
The economic benefit is increased after the reinforcement is strengthened by cold working. But the yield strength of cold processed steel bar is relatively large, and the safety reserve is small. So what grade of steel is a cold-rolled ribbed steel bar, and what are its advantages?
Cold rolled ribbed steel bar has many advantages in our use. Its steel strength is high, which can save construction steel and reduce project cost. It can save about 40% steel when used in the cast-in-place structure; It can eliminate the phenomenon of the anchorage zone cracking and steel wire sliding, and improve the bearing capacity and crack resistance of the end of the component; The cold-rolled ribbed steel bar is elastic and not easy to bend when pouring concrete, which provides convenience for construction
Advantages of cold rolled ribbed bar:
Cold rolled ribbed steel bar is a new type of cold rolled ribbed steel bar developed in recent years. Its production process increases the process of tempering heat treatment, has obvious yield point, and the strength and elongation indexes are significantly improved.
The steel has high strength, which can save construction steel and reduce project cost. Compared with hot-rolled plain round bar, LL550 cold-rolled ribbed bar can save 35% – 40% steel when used in cast-in-place structure (especially in roof).
The bond anchorage performance between cold-rolled ribbed bar and concrete is good. Therefore, when it is used in the component, the phenomenon of cracking in the anchorage zone and steel wire sliding is fundamentally eliminated, and the bearing capacity and crack resistance of the end of the component are improved; In reinforced concrete structure, the crack width is smaller than that of plain round steel bar, even than that of hot rolled thread steel bar.
The elongation of cold-rolled ribbed bar is higher than that of the same kind of cold-rolled steel.