DEVELOPMENT LENGTH - AS PER IS-456-2000

 

DEVELOPMENT LENGTH - AS PER IS-456-2000


*The development length Ld. is given by

                    𝑳𝒅 = 𝝓𝝈𝒔/ 𝟒𝝉𝒃𝒅

Where,

      𝝓 = nominal diameter of the bar,

    𝝈𝒔=stress in bar at the section considered at design load

   𝝉𝒃𝒅=design bond stress

NOTES:-

 1.      The development length includes anchorage values of hooks in tension reinforcement.

 2.      Design bond stress in limit state method for plain bars in tension shall be as below

Grade of concrete

M20

 

M25

M30

M35

M45 & Above

Design bond stress,  N/mm2

1.2

1.4

1.5

1.7

1.9

3.      For deformed bars conforming to IS 1786 these values shall be increased by 60 percent.

4.     For bars in compression, the values of bond stress for bars in tension shall be increased by 25 percent.

 


 

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