How do you calculate hook length?

How do you calculate hook length?

The below standards are most important in calculating the hook length and bend lengths at corners while finding cutting length of stirrups.

1. 1 Hook length = 9d or 75mm.
2. 45° Bend length = 1d.
3. 90° Bend length = 2d.
4. 135° Bend length = 3d.

How do you determine the length of rectangular stirrups?

Cutting Length of rectangular stirrup = Perimeter + Hook Length – Bend length.

What is hook length in reinforcement?

1. Hook Length or Cutting length of Stirrups:- The hook length is commonly provided for stirrups in beams and ties in columns. In general, Hooks are added at the two ends of the rebar in stirrups or ties. Hook Length = 9d (d is dia of the bar)

What is the hook length?

Hook Length: The hook is the extra length left at the 4th corner of a stirrup so that the stirrup retains its shape. Generally, hook length is taken as 9d for one side. Where L = length of the bar for stirrup.

How do you calculate the length of a steel bar?

If we put 1 meter length for each diameter of steel bar in the formula then we will get the unit weight.

1. 6 mm ø bar = 6² x 1/162 = 0.222 kg/m.
2. 8 mm ø bar = 8² x 1/162 = 0.395 kg/m.
3. 10mm ø bar = 10² x 1/162 = 0.617 kg/m.
4. 12mm ø bar = 12² x 1/162 = 0.888 kg/m.
5. 16mm ø bar = 16² x 1/162 = 1.580 kg/m.

How do you calculate the length of a beam?

Example of Beam Reinforcement Calculation:

1. Length of B1 = clear distance between walls + 2 x width of walls – 2 x bar cover + 2 x bend length.
2. Length of bar B2: A + B + C = 4000 + 2 x 230 – 2 x 40 + (1.414xH – H)
3. B2 = 4000 + 2 x 230 – 2 x 40 + (1.414×334 – 334) = 4518.3 = 4520mm.

How do you measure rebar stirrups?

Steps involved in finding the cutting length of stirrups

1. Look at the size of column or beam from drawings.
2. Adopt Dia of the bar (generally 8mm Dia is used for stirrups)
3. Deduct the concrete cover or clear cover.
4. Find the total outer length of stirrup after deducting concrete cover.

How do you measure the length of a rebar?

Measure the entire length of the concrete slab. This is your slab length, or “SL.” As an example, assume your SL is 50 feet. Calculate rebar length for the slab — “RL” — using the formula: RL = SL – 0.5 units.

What is hook in rebar?

After placing rebar in a host, you can modify rebar properties to assign hooks. Rebar hooks have a matrix relationship between the hook angle and rebar size. The rebar hook type comprises a defined hook angle and initial hook length. If the existing hooks are appropriate, you can start this procedure at step 7.

What is hook length and why it is provided?

Hook is provided in stirrups for the following reasons: To prevent from buckling of column. provide a sufficient extension of the length of the bar beyond the point where the steel is required to develop its yield stress and this length must be at least equal to its development length.

What is the hook formula in stirrups?

Now we have everything to calculate the cutting length of our example diamond stirrup. And the formula is, = (4 × arm length) + (2 × hook length) — bend deduction.

How long is a length of rebar?

​Typical lengths are 20, 30, 40 and 60 foot, but custom lengths are available. ASTM A615 is produced in grades 40, 60, 75, 80, 100. ASTM A706 is produced in grades 60, 80.

How to calculate the length of hooks of a rebar?

In general, Hooks are added at the two ends of the rebar in stirrups or ties. Hook Length = 9d (d is dia of the bar) Below image makes you clear why the Hook length = 9d. From above fig, length of hook = [(Curved Portion) + 4d] = [(4d+d)+4d] = 9d. Hook Length = 9d [d is Diameter of the Bar] Example Calculation considering stirrup with the hooks

How to calculate the bend length of a bent bar?

To calculate the bend length the below procedure is followed. From the above figure as the bar is bent at an angle θ 0 the additional length (l a) is introduced. Where, l a = l 1 – l 2 – (i) Tanθ = D/l 2 ; Sinθ = D/l 1

How to calculate the total length of crank bar?

To keep the crank bar in position, an extra bar of length (L/4) is provided below the crank bar as shown in the below figure. Therefore, the total length of bar = L+0.42D+0.42D+ (L/4)+ (L/4) = 1.5L+0.84D Below table represents the total length of bar calculation for different types of bar shapes.

What is overlap length in reinforcement (bar bending schedule)?

Overlap Length / Lap Length in Reinforcement (Bar Bending Schedule) :- Suppose the length of building is 20 m. The standard length of Rebar is 12m. We have to join two Re-bars for the total length of building. In order to Join the two bars (overlap). Overlap length is adopted.