ERRATA. Figure GL. 2 TRANSVERSE CROSS SECTION OF A SCREW SLOT

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1 srew slo: a semi-hollow in an exrusion inended o reain a srew arallel o he axis of he exrusion. (See Figure GL.). Figure GL. TRANSVERSE CROSS SECTION OF A SCREW SLOT self-drilling srew: a srew ha drills and as is own hole as i is eing driven. servie load: load under whih servieailiy limi saes are evaluaed. servie load ominaion: load ominaions under whih servieailiy limi saes are evaluaed. sli-riial onneion: a oled onneion designed o resis movemen y friion on he faying surfae of he onneion under he laming fores of he ols. siffener: a sruural elemen aahed or inegral o a memer o disriue load, ransfer shear, or reven. sruural omonen: memer, onneor, onneing elemen or assemlage. sruure: an oje, inluding u no limied o uildings, walls, fenes, owers, idges, railings, signs, and luminaires, designed o suor loads. aing srew: a srew ha hreads a reformed hole as i is eing driven. hread uing srew: a aing srew ha is insalled ino a reformed hole, wih inernal maing hreads formed as a resul of uing ou he maerial eing aed o form he relief area of he hreaded shank. hread forming srew: a aing srew ha is insalled ino a reformed hole, wih inernal maing hreads formed as ow of he maerial eing aed ino he relief area of he hreaded shank. orsional : a mode in whih a omression memer wiss aou is shear ener axis. unaed lengh: he lengh of a memer eween ae oins or eween a ae oin and a anilever s free end, measured eween he longiudinal enroidal axes of he aing memers. For olumns, ae oins are exural or wising is resrained for orsional. For eams, ae oins are oins a whih he omreseion or he ross seion is resrained agains wising. weld-affeed zone: meal wihin 1 in. (5 mm) of he enerline of a weld. Marh 15 I - 19

2 B.5. Radius of Curved Elemens The radius of urved elemens R shall e aken a he mid-hikness of he elemen. B.5.3 Thikness of Elemens For uniform omression on elemens wih linearly varying hikness wih δ <.: A wz = ross seional area of he weld-affeed zone A g = gross ross seional area of he elemen. B Fla Elemens Suored On One Edge The sress F orresonding o he uniform omressive a elemens suored on one edge is: LIMIT STATE F / a) For aered hikness elemens wih he hik edge suored and he hin edge free, he slenderness is (1.1δ)(/ avg ). ) For aered hikness elemens wih he hin edge suored and he hik edge free, he slenderness is / avg ) For aered hikness elemens suored on oh edges, he slenderness is / avg. = elemen widh avg = min max max min (B.5-1) = average hikness of he elemen = minimum hikness of he aered hikness elemen = maximumhiknessofheaeredhiknesselemen δ = max min min (B.5-) B.5.4 Srengh of Elemens in Uniform Comression The sress F orresonding o he uniform omressive srengh of elemens is: For unwelded elemens: F = F o (B.5-3) For welded elemens: F = F o (1 A wz /A g ) F w A wz /A g = F o F w = yielding F / < λ 1 inelasi B 5.D / λ 1 < / < λ in olumns whose axis is no an axis of symmery: elasi ( 5. / ) in all oher olumns and all eams: os- λ = λ = B 5.D / > λ (B.5-4) sress orresonding o he uniform omressive srengh alulaed using Seions B hrough B for an elemen if no ar of he ross seion were weld-affeed. Use onsans for unwelded meal (Tale B.4.1 or Tale B.4.) and F. sress orresonding o he uniform omressive srengh alulaed using Seions B hrough B for an elemen if he enire ross seion were weld-affeed. Use onsans for weld-affeed zones (Tale B.4.1) and F w. For ransversely welded elemens wih / < λ 1, F w = F o. k B E 5. / C 5. for elasi k 1 B 5.D for os- / > λ B.5.4. Fla Elemens Suored on Boh Edges The sress F orresonding o he uniform omressive a elemens suored on oh edges is: LIMIT STATE F / yielding F / < λ 1 inelasi B 1.6D / λ 1 < / < λ os- B 1.6D k1b λ = 1.6D k BE 1.6 / / > λ Marh 15 I - 37

3 LIMIT STATE F / yielding 1.5F / < λ 1 inelasi B 3.5D / λ 1 < / < λ elasi 3.5 / / > λ λ = B 1.5F 3.5D C 3.5 ( ) B Fla Elemens Suored on Boh Edges and wih a Longiudinal Siffener The sress F exural omressive a elemens suored on oh edges and wih a longiudinal siffener loaed.4d 1 from he suored edge ha is in omression is: LIMIT STATE F / yielding 1.5F / < λ 1 inelasi B.9D / λ 1 < / < λ os- λ = B 1.5F.9D k1b.9d X k B E (.9 / ) / > λ The momen of ineria of he longiudinal siffener I L aou he we of he eam shall equal or exeed I L =.α s f E A s 1 6 L.4 3.4d 1 d 1 X (B.5-14) (see Figure B.5.5) A L = ross-seional area of he longiudinal siffener d 1 = disane from he neural axis o he ange f ange = lear heigh of he we s = disane eween ransverse siffeners = we hikness α s = 1 for a siffener onsising of equal memers on oh sides of he we = 3.5 for a siffener onsising of a memer on only one side of he we For a siffener onsising of equal memers on oh sides of he we, he momen of ineria I L shall e he sum of he momens of ineria aou he enerline of he we. For a siffener onsising of a memer on one side of he we only, he momen of ineria I L shall e aken aou he fae of he we in ona wih he siffener. B Pies and Round Tues The sress F exural omressive srengh of ies and round ues is: LIMIT STATE F R / uer inelasi lower inelasi elasi C λ = C R B D R / < λ 1 B D R λ 1 < R / < λ R 16 1 R / 35 R / > λ Figure B.5.5 FLAT ELEMENT WITH A LONGITUDINAL STIFFENER B Dire Srengh Mehod As an alernae o Seions B hrough B exure wihou welds, he sress F exural omressive srengh may e deermined as: I - 4 Marh 15

4 Chaer E Design of Memers for Comression This haer addresses memers sujeed o axial omression hrough he enroidal axis. For memers wih longiudinal welds, he nominal memer srengh is: E.1 GENERAL PROVISIONS The availale omressive srengh of memers is he leas of he availale srenghs for he limi saes of memer (E.), loal (E.3), and he ineraion eween memer and loal (E.4). The availale omressive srengh (φ P n for LRFD and P n /Ω for ASD) shall e deermined in aordane wih Chaer E P n is he nominal omressive srengh and φ =.9 (LRFD) Ω = 1.65 (ASD uilding-ye sruures) Ω = 1.85 (ASD idge-ye sruures) E. MEMBER BUCKLING The nominal memer srengh P n is P n = F A g LIMIT STATE F (E.-1) yielding F λ < λ 1 inelasi elasi λ = C ( B D λ) B D C C λ λ 1 λ λ 1 < λ < C.85π E λ > λ λ λ = greaes olumn slenderness deermined from Seions E..1 and E... For memers wihou welds deermine he nominal memer srengh P n = P no using B, D, and C for unwelded maerial using Tale B.4.1 or B.4. and F. For memers ha are fully weld-affeed deermine he nominal memer srengh P n = P nw using B, D, and C for welded maerial using Tale B.4.1 and F w. For memers wih ransverse welds and: a) suored a oh ends wih no ransverse weld farher han.5l from he memer ends, P n = P no ) suored a oh ends wih a ransverse weld farher han.5l from he memer ends or suored a only one end wih a ransverse weld P n = P nw, P n = P no (1 A wz /A g ) P nw (A wz /A g ) E..1 Flexural Bukling (E.-) exural, λ is he larges slenderness kl/r of he olumn. The effeive lengh faor k for alulaing olumn slenderness kl/r shall e deermined using Seion C.3. E.. Torsional and Flexural-Torsional Bukling exural-orsional, λ = (E.-3) F e F e is he elasi sress deermined y analysis or as follows: a) For douly symmeri memers: C w 1 F e = GJ ( k L ) I I z z x y (E.-4) ) For singly symmeri memers y is he axis of symmery: F ey Fez 4FFH ey ez F e = 1 1 (E.-5) H ( Fey Fez ) ) For unsymmeri memers, F e is he lowes roo of he ui equaion: (F e F ex )(F e F ey )(F e F ez ) F e (F e F ey )(x o /r o ) F e (F e F ex )(y o /r o ) = (E.-6) I I r x y o = x y (E.-7) A H = 1 F ex = F ey = x k xlx r x k yly r y y r 1 C w F ez = A r GJ ( k L ) g o g (E.-8) z z (E.-9) (E.-1) (E.-11) I - 44 Marh 15

5 In he as-welded ondiion, he disane eween he edge of he ase meal and he oe of he weld is ermied o e less han 1/16 in. ( mm) rovided he weld size is ale. J... Fille Weld Effeive Lengh lle weld s effeive lengh L we is he overall lengh of he weld, inluding oxing. If he effeive lengh is less han four imes is nominal size S w, he effeive weld size shall e onsidered o e 5% of is effeive lengh. lle welds shall no e less han he greaer of four imes he weld size and 1½ in. (4 mm). lle weld is 1S w. J..3 Plug and Slo Welds The effeive area A we of lug or slo welds is he nominal area of he hole or slo in he lane of he faying surfae. Slo lenghs shall no exeed 1 imes he sloed maerial s hikness. J..4 Sud Welds The ase meal hikness for ar sud welding shall no e less han 5% of he sud diameer. The ase meal hikness for aaior disharge sud welding shall no e less han 5% of he sud diameer. J..5 Srengh The nominal srengh R n lle, lug, and slo welded joins shall e he lesser of he ase maerial srengh for he limi saes of ensile ruure and shear ruure and he weld meal srengh for he limi sae of ruure as follows: (a) For he ase meal R n = F nbm A BM (J.-1) () For he weld meal R n = F nw A we (J.-) F nbm = nominal sress of he ase meal orre- sonding o is welded ulimae srengh from Tale A.3.3 or Tale A.3.3M F nw = nominal sress of he weld meal orresond- ing o is ulimae srengh from Tale A.3.6 A BM = ross-seional area of he ase meal A we = effeive area of he weld F nbm, F nw, A BM, and A we are given in Tale J... Load Tye and Direion Relaive o Weld Axis Tale J.. NOMINAL STRENGTH OF WELDED JOINTS Meal Nominal Sress F nbm or F nw Effeive Area A BM or A we COMPLETE-JOINT PENETRATION GROOVE WELDS ension or Base F uw S w L we omression normal o Weld F uw S w L we ension or omression arallel o ension or omression in ars arallel o a weld need no e onsidered in designing welds joining he ars shear Base.6F uw S w L we Weld.6F uw S w L we PARTIAL-JOINT PENETRATION GROOVE WELDS ension or omression arallel o ension or omression in ars arallel o a weld need no e onsidered in designing welds joining he ars shear Base.6F uw S w L we Weld.6F uw S w L we FILLET WELDS shear Base.6F uw S w L we Weld Q.6(.85F uw ) S we L we ension or omression arallel o ension or omression in ars arallel o a weld need no e onsidered in designing welds joining he ars PLUG AND SLOT WELDS shear Base.6F uw see J..3 arallel o faying surfae Weld.6F uw STUD WELDS shear Base.6F uw π D /4 Weld.6F uw (π/4)(d 1.191/n) ension Base F uw π D /4 Weld F uw (π/4)(d 1.191/n) Q lle welds loaded ransversely shall e aken as 1.36 imes he srengh given in Tale J... W F uw for ase meal is lised in Tales A.3.3 and A.3.3M. E F uw ller meal is lised in Tale A.3.6. J..6 Cominaion of Welds lle, lug, or slo) are omined in a single join, he srengh of eah shall e searaely omued wih rese o he axis of he grou in order o deermine he srengh of he ominaion. Marh 15 I - 57