How to calculate staircase steel quantity ?

Calculating the steel quantity required for a staircase involves several steps, including determining the number and size of rebars needed for each element of the staircase, such as the treads, risers, and strings.

Here is a general method for calculating the steel quantity for a typical reinforced concrete staircase:

• Determine the dimensions of the staircase, including the width, height, and length of each tread and riser.

• Calculate the volume of concrete required for the staircase. This can be done by multiplying the width, height, and length of each tread and riser, and then summing these volumes together.

• Determine the steel reinforcement required for each element of the staircase. This involves calculating the number and size of rebars needed for the treads, risers, and strings.

• Calculate the weight of the steel reinforcement required for each element of the staircase, based on the number and size of rebars needed.

• Total up the weight of steel reinforcement required for the entire staircase.

Here are some formulas that can be used to calculate the steel reinforcement required for each element of the staircase:

Treads: 

The number and size of rebars required for the treads depend on the dimensions of the tread and the required spacing of the rebars. One possible formula is:

No. of rebars = ((Tread width - clear cover) / spacing) + 1 Rebar size = diameter in mm

Risers: 

The number and size of rebars required for the risers also depend on the dimensions of the riser and the required spacing of the rebars. One possible formula is:

No. of rebars = ((Riser height - clear cover) / spacing) + 1 Rebar size = diameter in mm

Strings: 

The number and size of rebars required for the strings depend on the width and thickness of the strings. One possible formula is:

• No. of rebars = (Width of string * Thickness of string) / (Spacing * Spacing) Rebar size = diameter in mm

• Once the number and size of rebars required for each element of the staircase have been determined, the weight of the steel reinforcement can be calculated using the formula:

• Weight of steel reinforcement (in kg) = (No. of rebars * Length of each bar * Density of steel) / 1000

• Note that the density of steel is typically around 7850 kg/m3.

Overall, it's important to consult with a qualified structural engineer or construction professional to ensure that the calculations and design of the staircase are accurate and safe.