Table of Contents
What is the need for reinforcement?
Reinforcement for concrete is provided by embedding deformed steel bars or welded wire fabric within freshly made concrete at the time of casting. The purpose of reinforcement is to provide additional strength for concrete where it is needed.
What are reinforced concrete column used for?
Reinforced concrete (RC) is widely used for construction all over the world. Columns transfer the loads from beams and slabs to foundation. Columns support high compressive forces in mega structures such as long-span structures and tall buildings.
What are the two types of reinforcement used in a column?
These columns consist of structural steel or cast iron column enclosed with concrete, reinforced with longitudinal as well as spiral reinforcement.
What are column columns in reinforcements?
Columns are essentially required with the primary longitudinal reinforcement and lateral ties to avoid buckling of the primary bars. The details of minimum and maximum limits of reinforcements, minimum no. of bars, the size of bars, cover requirements, diameter, and spacing are given in the above picture.
What is the minimum area of longitudinal reinforcement required for columns?
According to ACI 318-19, section 10.6.1, the area of longitudinal reinforcement should not be less than (0.01*Ag), and not greater than (0.08*Ag). Where “Ag” is the gross cross-sectional area of the column. The minimum reinforcement ratio of (0.01*Ag) provides resistance against bending moments not accounted for in the analysis.
What are the advantages of reinforcement in RCC structures?
When designing RCC structures it is assumed that the members are rigidly tied at their ends. Providing reinforcement in columns effectively ties them with beams. Without reinforcement, the size of columns will increase to some extent. Reinforcement steel enhances the ductility of the member and the structure shall resist earthquakes better.
How much reinforcement do I need for a 400×400 steel column?
In a square 400×400 section with the stirrups placed in a rhombic layout (having 4+4 corners), 3000 mm2 total area of required reinforcing steel and use of longitudinal rebars up to Ø20, the usual reinforcement is 4Ø20+12Ø14 [*] NoteFrom table 1 derives that 4Ø20+12Ø14 correspond to 4*314.2+12*153.9=1257+1847=3104 mm².