Section 30 Chimneys ‘SHIH-LUNG CHU ‘Associate and Wend, Sutil Anaya! Divison Sargent & Lundy, Engineers, Chleag, i. ‘SHU-JIN FANG ‘Associate and Ansatant Head, Structural Anya! Ditton ‘Sargent & Lundy, Engineers, Cicage, MAX ZAR Formerty Parnes and Manage of Struct Deparment ‘Sargent & Lundy, Engineers, Chicago, 1. Mateiin Almost all chimneys in the United States are butt of reinfrced concrete ‘or welded stel. A few chimneys for commercial installations are constructed of radial brick, but because of the labor cost they are sed only for short chimneys. The decison tw build chimney of conerete or ste! (the latter are frequently called sacks) i bash ‘on cost. The economic comparison must Inelude the costa linings foundations seronantica-obstruction lighting, acess platforms, ladders, and in sore cases Steel stacks superimposed om building roofs impose @ cost penalty onthe building struc ‘ural steel and foundations, on he het od 2 Olameer and Height" Chimneys are constructed for fue gas emission; the height a top diaineter depend on the gas temperatures, volumes, and esved eal veloetties. The hiinney configuration should be selected to minimize construction cost ‘The chimney and ite supporting system should he designed to resi tress re ing lea load, wind or earthatake loads (whichever are greater), tack date, an cats: Furthoemore the reson vibration te to yan pressure should he condered, However, Timited to these loadings, W202 Chimneys ) 3. beadtonde Deal load howl ince the weigh fing nptation, hy ach, clinging. ash ander lad we sind Loads, honeys and sacks shone desig co rei hotter slongssid and cyocsind ditertions. kv addition, he vara omferencc ofthe hel should be considered se Loadn Provisions for determination ofthe alang-wind loads (drag ous) To te» RSMEJANSTSTS-1 and ANSI ASB For many years, ACL-307 x itn Butidng Cove (UBC) specie horizontal wind lal a8 wiform pres Itesatng one one wee Peas ae Fae Wound anon the geographic ares a5 specified Inthe w these! sr and on ee athe deg enlorced-conerele chimneys ant wel tae Teen aandeading provisions af Rele 1 and require consideration of wind fist elfets on chirmneys an tacks and do n0t ve the reso lo Fon reer one goT [1088) reires that wind Toads on comerete chimneys be cal fated the tum al two components, one caused ya ean wind the ther {ated scaling wind gots The sean wid lad contribution i proportional to the caused le retereace win speed The dynamic compnent i evaated wing mi Fee ees approsc as deseyed by Vebery t depends the natural Freeney ree eimctne properties af the chimney. A similar along-vind load provision aa eae ee oak CICIND Medel Cade for Concrete Chivmeys bythe International sti Chimneys “ved in the ASME standard on steel tacks? where the commenced. This approech follows that oe the gat espa actor fem slturbwlence avert fastest nied Hom of ACL-R07 give atest Fright Sc dation eases eet sty haa world ret ron the eons aeeieeigmetheFAe ACI dyna along-wind provision ie Basen mone ferent feStarch en Is formulated specially for chlmeys and tacks “AST ABH L-AZ contains fhe base wind-spced map associated with pi Ae tacnoe uf .02 (see also See. 21, Fig. 3) Ths win wap freere Hey Er Say and ASME. STS I for determination f wind loading on concrete ch Drstee stack Een Tos du ta Vortex Shedding (ee also Art 19). Wh | ented toa steny wind, the periaiesheiding a vortices wil [eSrceton r-nverseto that of the wand ig Ya. vo acne natural feeeney ofthe chiomey. nay Gooog ofall permanent comstrction and “An alternative appreach i rnp conventional gisteesponse factor method ‘GEANSI ASB. Tor flexible bulings na to account and the dyna it should be he wit f bution which aly with chimney ending ynonnents at higher tevels in Fla. Oscillation de ster seg: eases (oval CDastZ/ iD chete 8 © evtial damping ratin of chiganeys se 0.015 for conenete chimney 1.005 eae tacks ml 4.0 for lied steel stack nes overseas | cen el face Ref. 2 for further discussion) he Wind tonsa 209 hed of chimney, git pe unit neva top hd of cnoy, base of chimney to its hens Bas of chine to postion under conertion, to Sgn nid oes tea wid vey, pe {C= coefficient given by Ee (a The dame wind pressures en by i ‘ie = 0.00128¥5 @ rn = ertial wind velocity for resonant transverse wibraion, given by Ea. (9) sD D for 205 Vn = IDs for Fos ’ where D, = outside diameter of chimney att By = oie ameter of times tae f= natural frequency of rs fundamental =e fondamental mode of transverse vibration of eh 5 = Strouhal number, varying frm 0.18 to The coefcient Cy Ba {1} wenisen yn 25 . or2t a“ St for B= Sand > 16 = 063 DB u for Fi > 05 and <16 (4a) oe 29 >. 0 DIDI + sp aD, <5 ‘The coefficient for Cin Ea 1) given by G06 forDgD, > 08 (ws 7096+ 0485 tn Beco mn asses th i" ing the dynamic influence of lysing they ¢ of vortex shedding, the equivalent sttic Geel at be fondned V-'>'1 gr ietween Bard 3 may e reduced bo uliing iby 1 1G P/O tie ke dein nas Nur wd speed Seite a Sin se BIO = eS o eh whet hms al Wind Velo fo Olin Vivato (Sea lo At 16) ato to = versa lel stack may aso be subject to Rexoral vibration inthe > : ‘plane ares f vores shel he lowest mote of ovaing vibration ascii compaied by me eM oF ° widerstion, fh vl ovaing frequency ran Fa, (3) the ented wind vel 's nearly twice the vortex-shedding Trequency. ty VY for ovaling vibration of thevtack (ps) m2 Fs (60)20-4 Chimneys ) “Then with f from Eq, (5) and = 0.2 (bs Cheam feeetie! Wind Min cee ofa dhinney chal ete The Bim mean vad of Verney sain lecel “The wind presente ncaa be computed frm ANSH ASS Trae Fallows am o.onasevy| “ shore Va th reference design wind speed ph fons Fie Vf ANSL ASS. a 7 ‘the height. in feet. at level considered: . Fig. 2 Wind pressure on cna ston §. Earmquake Forte Chimneys and stacks n cathe ares should be designed for ng cartgmake forces by evant ati Jats or dy nunc anayss are vem in ACT A07/ ASME/ANS STS-1© ANST ABB." and Ua" These standardn or ents may not yckl dhe stm carta forces. TI hope Mat there will hea recon athe fire atm santard sl cone cemater o mock in comptng earthy ones for chnmnes stacks Ome dates ealelateeatlague ie tthe loa ing coe or eases in which the chinmey has a depend rehome specteym met ieyesed See, 3 or te Het, Fat respanee spectra fora peak hiro nnn acceleration tu ge shot tm fe, 8, The spect th are enema to Sammlaive pacts ef a peeret The site-speeic design reponse fs bated bx {caling these response spevva the ain of peo ero acceleration fr the ste. The isllowing dni aioe ve suggested 5 percent for conerete chines. 3 to 5 pence foetined sect ache and to 3 percent fer vised tel tacks “The vesponsespeciraghemin Fg. Dare adeate for rock sls sites correspond ing ta sil profile ype $n Table 1. For eines ta he bug sites wit ou pole her Sror'Sy astesntare resonance factor shor he wae to tip the reponse Peete gven in Fig 3 toe the modi doug sesponse spectra in gree te dynamic interaction effet cm the chimney sel fe neil for rein foreelcconerete chirmeye 1 steel lining, However, itis important te ‘ae. rest ofthis interaction Tue gosta specific weight less eof the finer isles thaw om cevon elle tacked ean (6. Provore itera than the surrounding atmosphere, the pressure on th the outside This negative pressure at the thve-gas en be determined From p, = asaue( o ) where wD, = Sack det ates of ater Sick high above gv enance, = Ming ree pl ea TTS tempertoes of ath ‘nt The cnesin fie ten be ProseureDiteentae 30:5 fant level psi vere and #85. expectivels, °F abso enletund sane eee Sale be ayread af fn feces eas thesigh the chim nk int ‘ he chines the negative pres J EGATIRIETa Pe poe pesos Ths presone ‘0 ER oa se “yt : + eye § of eae i i ar ‘sverage horizontal response spect for Ig sin gro ape TABLE 1 Ste-Siructure Resonance Factors § (From Ret. 3) Profile Tye) ~ — ‘Tas pros one with: Rock ofanycharctvitic snatrial maybe character Si nal coches here te il coveryig rock ae table dow of Pole Te te eye innate sch 'wrsvave eloity erate han 500 pe, oF ths es than 200 fam heal pe rave il ays ie Tyee syap gt ee ese or hy conditioning tes " Alps ofsands gravee or i days OTSA vets rk are sabe Profile Taw This profiles one ith sf to mewn ti cay “ cand cand, laactevize hy 30 fac more af wll omen stil clay with or mitt inten es ed ‘or uther colwstonlese sale,al ie ressted by liner i nd by compesite action itt bu 7. Tempurstire Oterenéais Ali chimacys should be investigated for stresses remtin fromtempersture differential, A provedyre to calcolate the temperature gradient aco the chirmney shell air space (Fany),iulation, and liner is discusced in Re. 1. “A chimney with two or mote Inlet breeching openiogs will develop an uneven ts store ditbution around the circumference of the liner These diferentials produce an {unequal expansion which causes lateral deflection of gnifcant longitdinal ‘Rretes will develop when the liners restrained, This maximum differential occurs a ficel of the breecltng opening and exponentially deeays along the chimoey height. method to estimate the maximiry ferential along the circumference and {ts vertea! pro is dlscuss “integrally with the shell const § eed F ost Post San z [ son, see) Zoi 5 wos moon eel T 20041 (610) 2 (soa "8002000405 500603 70H G00 fe) G38) as) oN 260) (SHB) TART naroge gosta. °F (20) ia. External pesste curves (Fron Ref 7.) 1. ana Frequeney of Vibration ‘The natural frequency of vibration ofa stack ore rey with a constant diameter, uniform thickness and fined base is given by 1 asap \ fe sp /E . fn ir Qu, wy as where fi fundamental frequency. ps 7F = fandamental period. a, = nt weight of shel Thin? 1 pravity acceleration = 386 insect Modus of elasticity, pst Reinforced-concrete chimneys are ness varying from s min bottom, Steel ch and with soveral thickness of D,and effective height H, have ally bul sith air taper and withthe thik the thichnen sete fr sventh ate Gerth arr rated re tin es Fig). Several formas ora efetive dime developed to enable the natal frequencies tse ° | a o © @ : Fa. Stel stk: ee 2, oy ond 9.7) Srttemarig (arniOond Fee) Broced canny THTTSD anchor bls aa bate og (es Lypes to be determined by Ba, (10) The flowing formula ar sugges himneys with straight taper or traight top and fared otto ROU Re 8 uD tnt neal ‘ meals alata) o 1m: H, = height of straight segment; 17, ~ height of bottom (tapered) sexmer tsp tt gd mrt increased mass to be Set in vibrations Since there hi ht30-4 Chimneys “Then with fo from Eq, (5) and $ = 0.2, Vo = 1606 5 (61) re along the circumfer: Gireunferential Wind Moment. ‘The varzton in wind te which should be cence of a chimmey shell (Fig. 2) prrduces circumferent [counted for. The maximum moments are Mou = 0.31498? (tension on inside) Gat Mon = 0.2729R! (tension on outside) Gn where ¢ = wind prescure at level considered, pel 1 = yoean radius of chimney a sane level reprtel fro ANE ABA. 1 oF a follows ‘The wind pressure q can be 4 = 0.00256¥4| 6 Fig. 1 of ANSI ABB.L and Z: where Vp is the reference design wind speed, isthe befght, in feet, at level considered. Fig. 2 Wind pressure om cer stn, 5 eenqueks Forces Chimneys andl stacks in earthquake areas shoul fe desig seismic redtance. Provisions for computing earthquake forces hy equivalent stale an SSor dynam analysis are given in ACI S07," ASMB/ANSI STS-1," ANSI ABA.1.* and UBC! These standards or ores may not yield the same earthoake forces. 1 is lp tat there wil be a reconciliation inthe future among standard and coe committees veelsear unifed approach in computing earthake forces fr chimneys or stacks. One Should slways ealeulate earthypake forces using the reference acceptable to the Tnea! building code. ‘For cases in wh erponse-spect Fe the chitmey hae an independent lining. dynamic analysis by ‘method diseyesed in See. 3 or the Vime-history method way he Feamired te evaluate the interaction effet, Flastie response spectra fora peak horizon Crdund acceleration af 10g are show In Fig. 3. The spectra of this figure correspond ralatve probability of 50) percent. The site-specific design response is ubtained by Scaling these response spectra by the ratio of peak griund acceleration fr the site, The [lowing damping ratlos are gested: 5 percent for conerete chimneys, 3 t05 percent for lined stec stacks, and I to 2 percent for unlined steel stacks. he reponse sme onn i Sareea rnb Su lt correspond Ang to sil profile type 5: in Table 1. For chimneys toe stom sites with soil profile Tree Seortgy asite structure resonance factor shoal be wsed to muti the response Speetrs ven tn Fig. 3 to ban the medifed design response spectra veteral the dynamic interaction elfect on the chimney shell fs negligible force foreeseeSnercte chinmeys with independent steel lining, However, fis important te ictcrnine the setamieforee exerted onthe steel lining ava rest ofthis interaction Tronsure Diterendas, When a chimes comveys hot fe gas af a speciic weight les then the susrounding atmosphere, the pressure an the facile ofthe liner f less than on hevouteide, Ths negative pressure at the Hue-gas enteance, often called stack draft, ean be determined from » ) where WD, © stack draft, inches of water 1 = stack height above gas entrance, ft 1.8L tmospherc pressure at plant lve, ps r= temperatures of etmosphere and gas, respectively, “F abslte CF + eats cpt Fig can be aed to deterine the negative resture atthe Nea amas ume clunneys witht pore ror Negative prose sore neary For cases where an induced-draft fan forces gas through the chimney the negative pres sure is reduced and the chimney may ‘may operate under a net postive presse. alo be sumed to vary inca wth height, Powe Presee. This pressure 10 uN J 0 200! fs so] Doo3, ROK OKT * "ao 4% . i 7 Se ‘ SRO Hy AES pe ‘ acts ‘ a 2 ea ° ‘or “oe “oe os a8 oe Be 6 8 2 RO FOTO Fig. 3, Blatic avery mE horizontal responce spectra for Lg masinum grou aces Prom TABLE 1 Ste-Strcture Resonance Factors $ (From Rat. 3) Sally sein acer Sree cy sha Sf evtijng ok ar sable depoateo and peel ogee ramets ‘This profile one with deep coe yonlsso il " They ohesonlers slay cualiton. ining tes hers i deth exced 300 Wwe sal yes one pont sais raves, ot aye Diomrackarewatie Profile Tye 5, mi rofl one with soft medina ica sels ofl coe th eam ily and an hurry 98 for oe fal mec lay with with! neem ny and0-8 Chimneys ) the sme dimensions. An approsinat nt rl frequency canbe determined eam Ey. ( by osiog for ty the weight ofthe sll ety shes he late ‘The weight and thickness showld be the height owe the base "Base Hexbty may need toe conadere in determining. re swhenstacksare supported ona roof srvture ora steal frame, the transational andl Tonal spring constants ofthe support most be taken Into ace ‘STEEL stacks here a many choice af «partie t Seostc enane Tht of se sacs, ining appre, gaye, a acd The sitet empresa sy ony ea ne, Fra ake Seder tee tiac ae ant acoeot tvee helet yale Seana Se tthe a str hehe dante he fret Pe Seay oa tei er tec date Dy ways ae es econ ASTRA A36 f. AagS0AISib or CS Abner eberner el ed have be ‘ita epeencs nd ge SER Seales ran ewoemate ey ny ste snciae hl eed i se i ine Wheelers ature a te ck ny ber 16K anne hy the parent then Fae i eo Hetil tonenten rpc tise il face beng mre reset estan arequnel hed amines cones fone Mined ein pei " “etree sn thet ute Wht eat rng i a ener Ihe eal wt ain fl eo ‘ete hs neon nae rhe he oto les see new wl a sl ben othe ning el Sit : Ms. pes he erent aliens or desig, ati, usta unten of sel sks a hr rence : Seas heal np comprnive sree ue vv joni anced meen nb Strmited y r= xr a where 0.062521 Aly ~ Fall = wos - Oe \ ye! axon 18.000 + (L/r ) ). Creunterentat Stoners 30-9 1 = shell plate thickness, in, at the sce B= radlusuf shell in = length of stack betwees: points of lateral should be taken 28 the elective lng = radius of gyration = 0.707R. ‘The factor Yin Fa. (14) 8 intended to accent for a posible interact mn under considers pont. Fora sell EX ack height in ing stack, of esindrical shell buckling: which depends on (and conn bueKing whieh depen ‘The allowable ress ven by Eq 1) isbused on actafclety oho ace focal cuits whch lt hr i rearerate aeaonS RE H eect af oie cone ome he allvane may sat fy etn epee he gene ee Sypes of station aad lning role sad ie oneness gas the etn wane reo ha te he lace eee el ars i e ce Oceet pena 18 Cot yner unten sien i ed tthe jen of he aul ierscn of tals ore decree ete nal compreston tet rests fom the terial aca heehee Jmeton Wircencrml pete dctonsckhat ance Sicumfeenil forces ss esmencd NIE the eat sdaion ‘crcl te Nort ea of rwnrence i ness held be increased, he eytinder at the wy us) where W = aval bond C= wind oe other moment at junction ‘The total circumferential compression (i he tag hs QS AIN, ton 8 + OTR VT, + see VRB 118) where? = acute angle between cone wall and eylinder Py = external presse per unt area, po 1) thieknest of eylinder wall jn 12 thickness of cone wall tn ‘The reaiee area A a of the rng ace @ anf an) - oF 1% (3) replaced hy the cone radius R see 6. J Steet aulleger ivrepated tthe top af the tack otermedate rng aioe nay eb fespired. The purpose of such silering etn pret exeeve dedorationta tea shell der sind pre ssire an provide Seances he tk Intermediate stiffener spacing can he de nied by 220410 Chimneys } where Py = satle wind pressure, psf (Fable 1) 1 thickness of thinnest plate In section under consideration, ia D = stack diameter. in ‘To ensure a nominal tive of intermediate stifener, the spacing should be kept within 1.5 imes the chimney diameter. Intermediate stilfencrs should meet the following main requirements: (20) (20h (200) where § = section modulus, By = pressure differs 1, = moment of inert A, = cromsect Valves of L, and D should be in inches. The allowable bending stress F show he taken 28.0.6F» The allowable axial compressive strese F, may be taken af 12,000 pst In the taleultion of stiffener section properties, an area ofthe shell equal to 1.56¢VRi or the tres ofthe stifener, whichever Is smaller, may be Included. et ncn See Fig 55 132, Anchor Bote These should he designed to resist the net tension resulting from the den load Wh and the wind or earthquake moment M, a the stack base. The belt tension Fean be determined from =i Ms en where DY = date of ol cele, a and N = our of anchor bots, Sine the cle tation of the anchor bats conti ‘elletion of the stack, i 3 {o limit the allowable bolt tension a the roat of the thread to 15,000 psi even if strength bolts are used Alc, the bolt spacing should not exceed 5K ft and atleast bolts should he used, "13: Bane Ring for Anchor Boks Anchor-bolt tension is eccentric with respect to the chi rey shell, and an unctffenedl bare angle is normally insificient to take the ben Deflection ofthe base angle will increase Interl movements ofthe tack and will cater Ieee neta ceonary ering veces the cere tel and any cae necessary to provide a continuous Milfened base ring at ion shown in Fig ‘Aiternatively.a separate chair for each anchor bolt may he ved ‘Circumferential connpressvestrerec in the continu hare ring may be calcula as though lt were loaded with rncentraed loads Q = Fe i the pane of the ring (Fig. 7) The mai i bending moment, which ve ) ‘Base Ring for Anchor Bolte 30-11 ‘Windward anchor bolt and produces compression inthe ouside ofthe ving, i given by M,= Cr, (2) where © = coefficient from Table 2 tals of bolt cen inmey shell within 0.78 Van either se ofthe ar ofthe rin he calelated soe cl tering rerense Se the eeentty «tulle ‘igo placed on bh en fea sochorbok PO Vers eer, ‘Sugested designs of anchor-holtchais ae given in Ref 9, orev, FIG. fase ring ranch ts, asue2 No ofbolts Fora stack with a bell base the base: angle he by the horizontal eumponcot of fore ‘i et the ising load. The aon itor iessto keep seconde hewn tothe bending stresses se angle should be Hnted te 10, re come within af limits. = + rane Desgy 2 ground spore ADM set tack 190 tha toh. eTROR B= Toh ts ancntagge eee Bale off Gen ining, weit of share 1 pe The de Torte nS Brigette to x1 ler set te ore a ek ‘rr amen Tal ction 60 key MEM Helo 10 plate = 10.2 pt pete = ISS BeE 25 pt Welaht pe foot of helt = 28.5 > te = AE yf From Tablet Pe = 32 pl Then = 0060 x29 x a0 504,000 8h3012 caimmeys ) fom the plate thichnen fr coroson allowance, ne 4. M8 | goons ine . PRS OT 2120 Determine the allowable cet from Fa, (14), sting the evant height smn Ba (13 = 4120 pa He « POTICHE gcarn > Fe ooh In x 1000885 «B47 Fr OMe tanger a NO coon Sowa. Tua sion 9 elon op, Asie = Sich eco erate = Case rina) Ibe Bra MEM eae 58x ont oe an 28 9c = 2h £925. oeo4i7 a7 0 An te X60 x 025 © 942 int Sree os ET cy BOLIC 60 1 PEK RO, 12980002 12 gary ig i 2827 Dd e900 X aT = 7200 pd 368 7200 = BED pa OK te Sin the bse ve rquited sel hich 1201 below the 5 fal ta Be ein Ini seat the nd womert ad weight the he My = 38 19 60 x 190 + 25. 10 > 60 TO + 29 AZINE xm xan = 750,000 fh We = 894 60 4 OTH C30 4 LONI X 38+ 1383 x 40 = 167.000 snc ar CONt-o-cHNDE OMCTION (Art, 10) 694560 4 BPH 90 181 U8 WE stant doe Zaft to 38 = 1b. 000 8m Tb * Bran Ae ga a) eo Assume enteral presure = 2in water y= 2.x 6.4/2 = 0722 ps tana 2S a 0625 9 = 3.58 wel 0 Fm a, (16), witht = fy = Helo Jan UATE + 1.002 TTT RT (0 = eojang0 x mamas + 078 x o4raR VEN TATE + Lo02y/ 5 2 Sober From ta (17 #1, = att ‘30 380? 1 R090 00 ) Guyed Stacks 30-19 Ty 9X9 K Kandle: Amat P= natint One Eslective Mange (ig. 6) = 0.437501.58 VOOR OTEE 40.25) = 3.00! RingareaA 80 1s 30K Agog = LADS iO WS 2n 4 erat 2a Ring = 1.24 142.50 — OnIAF TAO 28 — 2809 + LE.22 ~ Bon 3.88" — 2508 3x95 Cane OK. ran ea TEINS ER BO Fr ay (18) = 158 Maxim lloae sing = 151 = 19 Try 9% 3 Kans ped 10 rom Eyl 23x10 % 108 8 Tinie 200 The scone to, here ed ‘AN TIO WTS: Assume rales oho eee = 43 in, Fur 20 ancl Dols fom ta (2) the reed at ara por Bye aes ane = 4.000 nea Use Bh bate, fr whi M4. Gaye Stacks For wos pat sites the space repel for gus and the anchors snakes the nse gieddsucks FM uncestaceaceyahere the aosem banana toaulequately brace plant sretaresso sta pone ane groan lesen Cea of ways spaced 126° apart arm the stack cictnference eilransogle Bot $5 hase nna ue ese catchy tea Pent of they hehe sr shell, * te. 1 he ter 1.02 in? Py Wf to force ina single yoy’ de to sind em take force shout hase of stack, 11> at hase due to vextrait of fn 18 ving aoe base of ace ‘moments forthe eesign of the sell shone noted thatthe stack hel rigidly athe py rig bat maces Tcl wing to the dee forces nthe intial sg of the winrar gay. Wit ae {saa The height ol the guy section atthe g tHe moment at Pe base, Te later shaved on an estinated p of the hase. ICs nol good practee to ase a thinner shel betsee the gy ring al ace, even hee thee An evahvation of the te masini tensian in the windbard guy depends on the scind fore the cmponents in ine with te wind anl gy theresa fil fon fn two leeward guys. the wind Force vm and le west the at factors. The approximations given below are helicged tobe slice ‘mine the size of gv requrted far a moral gaye sat The breaking strength B.S. of the guy elles sland be bose on a factor of salty shunt 2.5. An initial tension wf 82.9¢ HS, in all guys i reeommentied. With thes tata vad expacity’ af the winded gay ean taken an 3 5 lovee inthe leeward gussas lL XB.S. The revpuied breaking strength3014 chimneys } ‘can be taken as B.S. = 2.0.3 cin @ and a cable selected which has a corresponding imum bresking strength ‘Tre moments nthe plane ofthe guy ring canbe taken x brag om = casn( ees £2.) tus 028m oy whe = men atop ug gn ame bt hang fy gna aS Manto herzontal fonce do wd or exehaake tb Other notation fx shown in Fig. 8. We Fig. 8 Guyed stack, letennined as for ies he height ofthe shell acting ana ange ofthe rng can he sigs gO, Vr tients shold Be povided ssc ef ech ey ™ ein 3 Design get ulna Aste Ach 6% 139 oth se sed al nue 1 tome ay tor 308 bee oe op B= A Sethe oman a9 ed rk (trot ree sane Base moment My = EXERT 56 90h Cantever moment . ar SXBEX I asco ah orizontal win at guy ng (29) pe BHI X IOC + 6 29 100% 50 ABAD 9 gag, 12.480 Roqired able RS. = gE w SKA y ‘Resonant vnraions 9018, ‘Use XX 19 wire extrahigh strength grade wth mininnm breaking srenath ~ 58,300 by Use fll feaion = 0.2 X 58.200 = 11.660 Bb Leeward wack guy tension ~ 0.1 % 58,900 ~ 5930 orzonal compencot inline with sak yy = 5830 si 45° = 4120 fh Horizontal component in ine wth windward gay = #120 cos 60" = 2060 Th Horizontal wind fovce at windward guy = 12-480 Horizontal slack guy force at windward pny? 2060) = 4180 “otal horizontal ove rested by windward guy = 16.600 Mb Tension 23.4501 windward ay fll wind ~ 2800 58.300 Fata ey = Be hirey el tying Mima pate ches in. Dat 24k im coreson allowance adem TS adint 4 72 Antex aon oats wazsit 40 7E % 368 0.1875 = 7620? ae Steses at wiedmard guy: Pa Dead load © 26 3% 7.6 x 3% = 101 pt wi Me 3.70012 nn a Vertical component of guy tension, asemed dtruted by guy ving wer 15 in of shell = 16800 soy pa RTS TS = +1920 Net stress = = 101 4 1320 ~ 5900 = ~ 4681 px 26.502 S65 st abuse = Novae = xY= o0mase Lx 10 = 0085 x 28x 108 = 11493 oe Kin ie orem hit of hive. 1 Breed Sacks Where a sce! tack is adjacent to a propetly braced blag or structure, hv economical to provide aac hom he sack tothe desc oie Lal distance above the base (Fig Se), The dese of the shell star to iat toa stack excep tha the slack casted tong eld atthe brave Fos tne sec ek the stil the dack tothe adjacent srtetore ig 9) the mesimn reset aea nn can he computed rom By (3) ‘The moment Mf the brace ring cane determined fein M, = 0.25RP es) 875 Se 9 16 Resonant Vibestone Steel stacks are more susceptible to wind-inductel vibrations than other types of chimneys, There are numerous records of tcel sacks, conser designed for maximum probable wind or crthuake oree, sehich have experienced tert ‘ous vibrations fr stealy-sate winds of velocities of the order of Mito a0 phe Ava Eonseqence, ie generally ecenay to vestigate them or detaicwsed sey Meg the serous low-wind vibration problems have been with wae sock “The wind velocity at which the natural fequeney of varies sheng eas the natural frequency of the stack fgven by By), Wilh = 0.2 he fonmelsaee , 000 fo = Di x SO w 34104, 6) {th Vim miles per our an in foe. The value of for stacks ofthe pol Semay'be taken asthe mean diameter of Ihe tap one thr fthe stock in Fg,* prevent ovaling ofthe hong a 20.18 chinnays 1 Experience indicates that periodic vortex shedeling may be inhibited by the natura turbulence ofthe alrstrenn at the higher wind velocities and tha tf mt Mkely tn cer at velocities greater than 601 mph. Vortex shedding induced vibrations st higher wile fate of more ofa random nature rather than steady-state. Research®" shows tat H the ‘tial wind velocity exceeds 1-1 tines the design mean hourly wind vel ‘of vortex shedding on stacks may be ignored. However, tie 10 tical to proportion a steel stack so that the ertical the leet ovays nceseary wr pra il velocity meets this exter. Tr Fon the ertial velocity Is ow en tion, as determined from th ugh about 15 10 40/mph), the stress cue to dynamic delle uivalent stati fore of Eq. (1), may be within desi rally adequate iTwoticeable movement snot objer sign allowable bit always result im higher natural frequency and higher Tess eyelic herding stress. Other meane for increasing stack sllfness to preclude oe sete vorter shedding vibration effect are use of gnywire, providing laterals ‘res, and installation of vertical tillener. Use of refractory lining roth types of inings wil also have benetic Other than the sifinese method and proportioning of sto brlicalstrakes, ylindrial shr crs, a prevention of excertivesibrations, The damping ry are the use of tuned-anags dampers, placement the Mack, and installation ofa single hanging chain or Ifthe critical wind velocity afa proposed stack falls tweet ‘of configuration to raise the Irequency is recommended ‘Stacks which are toe lined should he investigated for vibration tion. They may need to be puyed or braced temporarily during these perio, Also. to i eretion he to install temporary spider. nk ings should he provided to protect shotcrete lining during ‘Cireuaferental stile vibrations. To guard eter is a m1 inferential stiffening rings sre vexed to ease the resonant velocity hove G0 wip ‘The ovaling frequency of» nillened Mack given by 3 (Ee Vent weve w = weight per uit es ne Riffeners. An effective seit of shell equal to 1-56 VI sho the moment of inertia ofthe rine io ana tack hetwe se sce ) A stack downwind of another stack say experience a lange resonant wid lad that cused in Art For ow fac ih entero enter sang eeceing 1 dlaineters ofthe lnget sac, no smpifeatio factor i ned feeder de However, if the spacing $ is of 2 to 10) diameters D an amplification factor = 0-16. but no greater han 16, esecommena Ror paca esther ie denetva further investigation by wind-tunnel tests or other experience nay be mecessary. Resonant Vibrations 90:7 ined ate 10 be 17 ad he foment ATA aod ‘) 1088 ‘The eaten in weight ofthe selling the soterete ning a ‘ome fot heheh swe he he (At 9) ne eH at B83 pad comme at Shell = 0.1975 « 0289 Ling = 13/04 “Then rom Fa 10) 9x1 122 Wat x 1a "The etc wn vlciy by By (26) is Vr = AT 19 % 139 = 41.6 gh = BI ‘The equivalent stati wind fore i deteriined by Fe Dy + Pi-evsraos Da10H 96 C06 ha he vssomiate (2) Wi a oom oy aa (a) e002) in The clued dame nos wad oer Follows: ™ " sian along wind forces at vavous hese at Height shove Aevosewind —Alongowind thebase fineee Int feveee ot 0 0 2 30 a 20 2 2a ie han he lng lesb he wp 8 a the she Cnet the ending ng os wind dan enn esponaich 13 percent fhe ack perce ager ae seen sf Iniahne ee Ste sae man sae ‘ef wind omen the deen cael at ‘nau vari. The veal vebiy he sly Fa (6, 606 f= 160 = 40. » Kan = 53.0 foe for = Buin fay1 ) 20-18 chinneye Wiraton to wind 30:18 Since these veloies ar les than 60 mp the sell nay be nbjet oovaling 2 intermediates. fom opting the cots of concrete, form, ad reinforcing steel fr varios shapes. I ‘Ss stuced 10 on centers smd provided: From Bq, 20) the ovaing regency ef he ack 's common to se a variable rather than a straight taper, forse sre fe = ORNILAL + 10X12 X 0.25) = 8:90 in 17. Act Standors” ACI 307 (Rel. 1) gives material, construction, and design require. ee iments for reinforced concrete chimneys. sets forth recommended loadings and eet 388. tonepe ‘ods for determining the recultingstresves. at Vas Wehbe ne hme are nly ey vonsctnueeme cig een ne, aoe tice ee a cb mag ieegewselcorancciontacaanet ony ce meg ae 104 x 10 the design velocity: Measurements ef vibrations are rove, and ere for comesete over 300 high, Since many concrete chinneys have nel experienced hic pablo he Hence the sifener provided are ete ogurd agit wind fcedovling bration. futors believe that tapered concrete himmeys of normal deters ad wa 30 ight as ns ily te r sees pcr neat ging indinend mao tn i ito experience tannerae resonant bration. For tale ehinmey seat Commute the % unasally slender proportions the procedure discussed in Atay be seal te eee 210 = 184 ve Pratl eeethe sec ies hes abe ise mutha arabe 2-1 (234) 08 na me ee rompers redcing on ntaltion ad opeting ces ted wt wih he selina Sct aig 183 and compl {eck oT ie se Depenng ihe ner nse ests lace a The eqoiva fe fonts the height sve the bee (Ae 8) Shell = 0.4975 0.263 = 0.124 laced agi the chimey sel independent sept str! Brings (Fi. 1) ae wed forcedconerete chimneys. They ar fully insulated and can be ost frequently to rein sported atthe bottom, Ung = Toa ous L O.251/0.4975 = 0.574 Ihjin® “Then rom B. (1, 39x 15712. /28 x 10f Coning. Cae 057 Lal ope Coping. a om B. (26) with D= 158 has the meen dante of the per thf the sack ett Ve 241% 185 181 = AS ep onretet. ste “The casa shone e cemared low to the din mean uty wind veacy Pro meet Dianicnhwenc foresee sheng ty he following eet mover Petar spo sam ge veom(F)%(S) rn) “where Un reference design wind speed in mph Ge the fastest mile wind sped at 35 shove td evel, tong 60 ph) 2 Kstanee fom the bast of sor tthe potion where the sack diameter i sl to SAD (AR 4) Teen Thos es iM : v= 07 (22) oo (22) = 07 ms com en : 1302789 oh < BS agh ona Since Vie > 1.A¥. the eff of verter shedlogon the sack may before Sagan enonceo.conner cers Sa ea comp ste with ground-supported reinforeed-concrete chimneys up to 200 ft above the Pi mastc. See coh eemenrtecye eee ter ob 2008 ee enact nnn Iromiceh Reinforcedconcrete chimes ssn cet fet ¢0 maint than ste! chimneys they ae fre rom atmonpheric coos cnerally eeonomical ta tape all concrete chines ith the op dlameter deter amined hy gee cut requivements ad lines construction details The hase diameter rests30:20 chimneys top, oF some intermediate level of the shell. Stee Fners a ly corrsion- fee Iehtere entering gos temperatres are above the ail dew point, provided thatthe exterior “Surfaces are properly insulated. A conting fr the interior surface shoul be considered ‘ntering gag temperatores below 250°F are expected andor the ys is saturates. Nit Steel liners have been built of A36 steel: A212 steel has heen used occasionally becom Of its improved atimspheric corrosion resistance, Since the AZIZ steels are not act Feslsting, their added expense may not be justified. Detailed dicussions of the design und ‘Construction of steel chimney liners ate given ia Ref 7. Tndependent, sef-napporting brick linings (Fig. 100) have been fementsare not severe Ta rede circunere i shoul have ene reately low each, eto the section shove brie ti thermos poplar typeof liner fr tnd red with heen de ‘gate The serubpd he iste so corrosive tat any commertl coals tnaled Iependent steel liners have experienced aril ofa fares Detaled sui ‘the design gl constrvetion of brick shiney ner are even nH. 16 and 17 Peril Bee ings supe conde Pi. 10). wh ox ec anit common inthe pat hve been the largest source of trouble fore tren to gas eakage an sce tack fsa feo ciferential verte expansion ining swppert ‘Shotrete ues applied over mesh wed entondvely Tore ace. Fxperience ves eter protection against corto tian port Flaten coment nt he ning should bet compound immediately afer sheer, sce Ingeive given satisactory service on coerce ch "Bik Linings for Se! Starke If the gases re gly corventv, wore el me experi. ning contigo ick ld cakr-sumivat ortar we mortar placed twee the brick andthe tel has heen weed (upper portion a Fg. 1) ‘The quality a the mortar can he nproved by ising highend and by cine te Joint with a sprayed merbrane The mst satisfactory rik fr this ning some com Iermingto ASTM Spectication C279. Atmore coy ng that appears to emer Wa tenance where highsulfurtveleare red const nick a odin sea ora ‘ithe mate etween the brick and he tet (lower porthin of F104). ual Wall Sel Sark A salva see stack fe mae np of to separate freston wel sheets withaseskedinslatedairspaceinitwcen The outer walls enced {ethane the srtctural,scrodvame (wind) and earthiake tots. The inner wall tiesigned to expand freely and fllywner al temperature conditions, The Seles isted ne space wil ep the bea Tos ton iian hp Seal condematton and correo attack, This typeof del sack hap cen fat greater Popularity tne Uatted States, Ax compared to Drilled sacks aud sheterte hed ack, thedualwall stack provider grater phe rise and bet eau itsthermal eficieney. [FOUNDATIONS Foundations of chimneys and stacks may be subjected to large overturnin rasa esult of wind or earthuake lonings, and it important to dnvestgate the snpporing fail or rock bee i rotation snmp sete ofthe nan wis ny movement ofthe top of the chime. ree eamerete foundations for charmeye are usally elrelar in shane. with cenforeing steel placed in the cireunferential and radial divetios except tn the center portion. where a grid of straight ars lisinatee bending elreuntertutilstel and ave he evn ection af hare inthe rail direction (Pig. 11). Where ehisineys are founded on som Belen rock or un eaissons or ples, ff economia to support tenn om etgshaped fn Satiome (Fig. 12 Medion al all chi “anne om retain Touodations vith veinforetng bare placed in foe dieetont (Fie. 13) ear may be steppe we sled. Stress eee eT Gaedaten fox where A = a(R — AY. The dist YYalues of ky and ky are given in Fig. 14a and b. In these Rgutes the eccentric W, where A= overturn Clreumferentio! bars Top and bottomreinforcing sot ressure is usually determined by considering the foundation aa irl whose rales the mean of the Inscribed and citeumscrhed ele ofthe vcore The soll pressure p atthe kewa ‘eamdnon or os a toe of a clreular foundation, or of a ring shaped ith nse radius, i given by ks vn = total Toad Rodial bors Grid bars center area tree. Section A-aFen. circumferent! ‘Top and bottom reinforcing plan ren. Top of rock Fig. 12 Ring foundation. ‘Dead load used inealewations should ince the weight bach, and the expected dist accumulation inde the chimney. unless 1 Pefoces the effect of horizontal forces, Checks should he made to ensure the Tae haters eptnat overturning and siding a edited Sn Sen. 7. Por rent design in accordance with ACI 318-83. and in the absence of live lon, ‘esun load thould be the larger of 0.90 + 1.3W and 0.9D + 1.46, but oot Tess than 1D. xanga 5 Design tapered octagonal foundation fr ese say, Allwae si Leeann ane ob ecole iermateton@ = 3" Tey amen rneter of 30 wth a Peet Oe ae ides LSU Fig 15) Fig. 13 Octagonal foundation of cir and ining Moment at bottom of london = 3 ‘203K 000 “e800 16t plocement Founatone Section AA san 167,000. Teil weight of foundation 202 ft ot3.5 x 150 af = 106,000 soe ne 25 % 150 gat = 149,000 sonRgiR*- Fig. 14 Soil preesre constants for ‘cla and ing foundations. Fa. 1S Sal preswure under fount, From Fg. Meand bby = 445 by = 105, From Bp. (20 and G0), = 282000 or f= 15 x 105 = 15758 ‘Shear rstance avilable at bee = 462,000 tan 30° = 267,960 367.960 actor of safety asin siding = 22 5.04 162,200 X15, actor of fey agai overturning = AS2200 2015 6 1.26 Use octagon based on 30-1 memn-dhameter cee, check asumed depth, and determine ried reinforcement REFERENCES 1. Standard Specictins for Desig and Contruction of Reiaarerd Camevete Chimneys ACI 07 © "Amerean Gonercte haste Det, Mich, RR Sse ASME ANSE STS-1-TOR, American Society of Mechanical Engineers, New York. Reterences 20:25 Bulg Code Requirements for Minseum Design Loud in Hailngs nd Other Structures, ANS ‘ASH. 1088, American National Standards tte, New York 188, Uniform Balding Code, Intereational Conference of Bulding Oficial, Whiter, Cal 1926 Uniform Building Code nteretinal Conference of uldng Oficial, Whiter Ca 1985, ‘Tentative Frovions forthe Development of Stare Regulations oe Baling Hep ATC 06, ‘Applied Techoology Coane, Sceand ping Apr 1964 “Design ad Contrcton af Steel Chaney Lines,” American Sockety of Chal Engineers, New Yor, 1075 ‘Ghu, Koang Han, and J. Park: Approsimate Fundamental Frequencies for Chimneys, J. Power Dio ASCE, Novetber 1973, "Stel Pate Engineering Dats.” vol. 2, American tron and Stee nite, Washington,DC, ‘Rove, RS Amplied Stress and Displacement a Ciyed Towers, Tans ASCE vl 125, 1960, pt. Bat Ms Probleme with High Chimneys, Gd Bg, Febery 1064 ickery. BJ. and RL Bas: The of Codified Approach to the Determination of Wied Louis on Chimney, ded Canadien Wind fg Worksop, Vancouver, BC. Apel 1981, 13, Vickery B f-and RT Bet: Acromerind Vbations of Structures af Circle Cove Setton parts Land J Wind Engineering and Acodganies, vo. 12 1983 pp. 49-97. 14, NemarN-MJ A Blame: ad KK. Kapur: Sela Design Spectr for Nuclear Pants, J Four Die ASCE. vl 89, November 1973, pp 308-315, 15, CICIND Mosel Cade fr Concrete Chimneys, part A: The Shel, International Commitee ow Indostal Chines Dumeldor October 1984 16, Fung. J. and M. Oropera: Acid Reusant Independent Brick Chimney Liner, prsested a 1980 ASCE Convention, ellywood, Florida, Ocaber 1080, 17, Katberger. 5-ond'8.. Fang Recent Development iw Materal Selection for FGD System, Proc ‘American Poser Convo 4, 198, 39 “fh