Roof Slab Reinforcement Calculation

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Roof slab reinforcement calculation.

In the united states a run of 12 inches 1 foot is used and pitch is measured as the rise of the roof over 12 inches. For example if the slab is 10 x 10 and the clearance is 3 the size of the rebar grid will be 9 6 x 9 6. Evaluate the length of the distribution bar calculate the value of d depth of slab top cover bottom cover find out the no. Of bars compute the total wt of steel required for slab reinforcement.

Steps to calculate the reinforcement required for slab deduct the cover for finding length of bar. Department of civil engineering n w f p uet peshawar design of reinforced concrete components of a house. The slab should be provided steel bars to withheld tensile force so this slab is called the rcc slab. Technically in the slab we give two different names of these bars main and distribution bar.

Subtract the clearance from the length and width to find the dimensions of the grid. This is needed to determine both the lengths of the rebar and how many rows and columns are needed. Lb la 16 12 1 33 2 two way slab minimum depth of two way slab is given by formula hmin perimeter 180 2 16 12 12 180 3 73 in assume h 5. The amount of result 3 divided by 20.

The one way slab is supported on two beams and then to the columns of the building. Outside of the u s a degree angle is typically used. The amount the waste factor will add in lineal feet. For instance a 7 12 roof pitch means that the roof rises 7 inches for every 12 horizontal inches.

Main bars are 12 mm in diameter 150 mm centre to centre spacing distribution bars are 8 mm in diameter 150 mm centre to centre spacing. 1 lintel and beams 1 to 2. 2 columns 1 to 5. Main bar distribution bar difference top and bottom clear cover is 25 mm consider development length as 40 d thickness of slab 150 mm.

4 roof slab 0 7 to 0 8. I have given an example for the calculation of the quantity steel rod in slab below. Before calculating the quantity of steel in one way slab it is very important to clear the basic concepts. Calculation of steel bars in beams.

The slab should be strong enough to bear the required load according to design. Amount of rebar needed in lineal feet. The bars we use in the tension zone of the slab is called bent up bars. The one way slab steel quantity calculation is done according to its supporting conditions.

Lineal feet of rebar plus the amount of waste.