TENSION DEVELOPMENT LENGTHS

For bars and deformed wire in tension, basic development length is defined by the equations that follow. For No. 11 and smaller bars,

where      <i class="emphasis">A</i><sub<i class="emphasis">b</i></sub> = area of bar, in<sup2</sup> (mm<sup2</sup>)<i class="emphasis">           f</i><sub<i class="emphasis">y</i></sub> = yield strength of bar steel, lb/in<sup2</sup> (MPa)<span class="inlinemediaobject"><img alt="Image from book"> border="0"> height="24"> id="IMG_368"> src="https://images.books24x7.com/bookimages/id_15147/p30001c21g1690005vpp.png"> title=""> width="20"></span> = 28-day compressive strength of concrete, lb/in<sup2</sup> (MPa)

However, l _d should not be less than 12 in (304.8 mm), except in computation of lap splices or web anchorage.

For No. 14 bars,

For No. 18 bars,

and for deformed wire,

where A _w is the area, in ² (mm ²); and s _w is the spacing, in (mm), of the wire to be developed. Except in computation of lap splices or development of web reinforcement, l _d should not be less than 12 in (304.8 mm).