....,... " TALL DesignandConstruction SNMANOHAR Chief CivilEngineer T8taCOl/suitingEngineels Bangs/ole TataMcGraw-HiIIPublishing Company limited 1001 NEWDELHI TorsteelResearchFoundationinIndia(CR) OANGALOnE J 0 ',985,TATAMcGRAWtIlLL ' "dBLtSHINGCOr-. tPANYLIMITED l'o'opariof this public ation can\.J1;l!;pn"luccLlinanyform or by;mymeans withouttheprior wri ucnpermi ssion ofthetWOpubl ishers, rata Mt Graw-llillPublishing CUIllP:l II)IUmilni. amithe TorllcelResnarchFoundati oninl nuia This edit ion canbe trOll)Ind;;[ oulybythe Anyopin:ons/slalcmcnls inthe hook are Ihll of lheilulhor andON necwarily thatof theunlessspecifically indicatedmhc,wbc Pubffshlll8 MOl/ug,,,:RAlI\I ProducllolIEditor:RAN/ANK"ul. Prod/le/ rOilA5Si510lll:n LDO(; p; ,\ Joint ly u,'dby Tal afo.h:(j l [1\\,- 1 hllI'uhl(" ..O'pallYLi ,,, j 1, ... 1, 1214 AI!HW1C.I ,NewIklllitill CHI!, alhl , 'Orslcc!Rc!;.._ chF, 'unllaliuninII UIi;I, 7,RrJ;ld,lIalllt:l1llro;:amipli,ue.I;1I ... jk:tm:l J Elcct ril.:Pless, 41 6) AryaPunl,Dt.' lhiIIU 001 ----, -' FOREWORD I IhaslOll!!establishedthatintroductionof T orstccllS ahi gh-strength,high-bond rein-forcingslcdIW.5 CIl lllributedsignificantlyinthedevelopmentofrei nforcedconcretedesign ;l lhlconslruclionallover Indiaandabro3l'.It hasbeenreali sedthattheuseof Torstcelin properl ystructureskadstoconservationof precioussteelresulti nginsubstantial ' Ju(' tion ill..: onSlrtJ(' (ionCOSIwithimproved struclur;Li cllicicncynotonl y insimple reinforced , IHll' rCIt:1;Jl'mh.'f S outal s .. )inC(llllrkx ,\ src scardlanddc\,\.. lnpmcntiscOlltinuouslytakingr 1uw;'.l1dknowledgeand cxperience \1\' ill!, l\ ' illi',IIt:Cl i l'(l nnclc l' IIIl Slrt1l'\i(11lisbeingrenJeredlIloreandmorcversatile, ;\ 1:l Il YClllH!, lil'::r.:damIsrceia ltypesof structuresl'ateringt oDo varietyof servicecondi tions \-ri h: ria:l r.;lW\\'l'Im,'ci\"cdand.:on..,trul lcdinreinforcedcon(" rctcmorecconomi- t!l:LIIwilh". rlll[lIr:l1masonr yI'r (1!l u.:rmatalal!' . rh,'pu l' Ii :; (; (,':1lif 1,'dIIIIL' :t 1 li\('r:ll u reinl' (HpOr:l1 in,!!well .:;. Ia blishcddesignprocedures ;: ndnil'.'r I.1:,:!"."11 111:11.: ' 1 ;1>011 ':"I'theImportantofTorSleel I{.: ...::ar.:ilI "'l!!hi:uiou's (nU' 1)h:l P-:";..y.J:..>... ..... ,-------------. . Fig. 2.1'"Plume Profiles . -the designh,I S 10bebasedon windspeedand directionaveraged over atime pe.riod as avail-ablefromawindrose.Sucha.time-meanwindspeed at areference heightis extrapolatedto givethe desi gnwindspeedat thetop of achimney.This windspeed can be usedinEqs. (2.6) III(2.9)forc$limatingtheplumerisc. Plume dispersionisancctcdbywindspeedsprevailing at downwind distancesand that 1('10 averagedoverahdght cQverclibythe dispersedplumc.Thi ..isto say thatintheplumc-dis-persi an c(\u;!tiul1thewindspeedto be shouldbetheoncprevailingatsomedistance downwindfromachimney and shouldbetheavcmgcforaheight to from theground.If Oz(whichisthl! deviationof the spreadofa plume)js >Hw/2. thentheaveragingheightwjllbefromgroundto 16TALL CHIMNEYS 2.5Estimating GLC GrowiUi;realisationoftheu.:nlton\nlflllIho: fr,lmp,)lluli, h"IH'h'r canaccuratelyrcpl'c,;enltl1l'!I"1fl. rogil, .dl'llnditi,lllS,then,Lll1rl'llftaraiu,cl(' ,11.;111.:':tll.: a,'CII THCYof predictcdGLC \'ari,' ';widdyd':pl'uding onthe ,kgr.:,PI'I1nili'rJuityin11I,'t.:"I-.' lo!!icalattheInm:lr1y :1I1:lIyli;::1Itel"l1l1i-Cluesyidd aCI.:c plabkresults c.'ulimll:dfWIllIkilt, f , I "'i I , o Fig. 2,2'"SrroAdof aPlunls Jnorder to forll1ulaleallIal hcmalil'almod;;1of plume dispersion, C.!dl':\nb.:o hl :l il Wdf romT,lhk (a)Aecur;Jeyof The,H'Cllracyo fd isp.:: r."j",),' ;ll!\ ' ,II Y h Ol t\lI '"I,',I!;\I;:'..Oil t heco m pkx j t Y (l r r It.:JI,i, 11\P hl'!LP IIll: III:t:>; 'c'n,: I ;l [cd\,.,11.'11.I i 1\,,; . \1h' ,', !Ill'I , ', ' Il iell condi ti ons,.:ll' ,T ill'Cttll:!li"Il " "h,\\'"I ll;1.1.:,;11,11.-1:,d. '.:;' ltll;,k110\\' c I' cl",t hl're;Lt"l' \',lll' l\11""" 1, 1': "bl'10 .006 1).(' L 30 O.III -tCI.CI.!L40 U.I)..!'1I.07l1U.lJ'JJ '" 0.IIJ10.012 U.I,).{,II. IN MII.U5.:! n.tu! It.'o!' 00.1150t.)'.!Ousn2.2W 4000.,'IOS):, ..wdliI __ inI h.:ul l r:lcrilio.:al Rcrange(Re >3.5 :-:Wr,).J1\ti,e:. II I',"' ("I"i l i';11 r: III,'t'O'[0' .3.:, :Id') Ill..:l'''lI1[of vortexseparation(lsciB:llcs1111;11 1a!c,"11.\Orll'X irregular.This is shoWJlinFig. :1.5, J

, I)Re-.::5 Regi me0\unseparctooflow ji) 5 " Rt?:eepl wherechimneys are supported0/\pilesIhmug.l1sortsoi l forwhicheasl.!f3- 1.2) J = import-Ddk.:l ioll .' " J..Ns'/m?,. - 4', -7",1/. -9" ,x 1;. I /JlJx 10' ---.--. 270+1 .000+1.11110+270.11\) H).2114 1 1 n.7l)S'J:'. 1..l.x."1... lIlomclIl "'" ! \ 106 31.:-::'i 1\"'111 TheseTesuils(':olllpar..:vcrywellwilhIh,l''':ohlainl"dInalr i\I' lla("lll1lpll (refer Table 4.7). .L__ --,'--_. -SEISMICEFFECTS T,uu4.7MODALVALTJU ----.. -Fir1t mode ... Second mode M.,I,..NOlle ------share ComputerManualComputerManual 1 l ~ l y . s l smethodanalysismethod -11.0001.0001.0001.000 20.12310.723-0.0247'-0.029 , 0.39610.396-0.7721-0.780 40.0%10.0%-0.4418-0.446 Inertia1+78.42+78.30-143,$2-.143.10 loa.ds2+121.93+121,69+8.00+9.46 kN , +85.61+83,44+305.01+301.77 4+20.76+20.71 +114.'2+17' .79 -_... Participation raclorUt2 1.$12' -0.'5' -0.757 - ---- ---- _. ' 1 .d ." ., .'.,._' t" " ". TEMPERATURE ._-_ .. _------ - ---.. ------The:- hl'l l (If .1d. imllc)'h: IS t< I\\" il a ll .!111.:or:1 I hcnH;,1rr:ldil'lHprevaili, anossil l>thickness.Asa or a1.: lI1p,' j .III1lC:, I';ldi';lIl.,".; 11;(.",,1:lIldci r,' umfcn'l1l i st rCSf>CSa rcdc\'clopct.lwhose":t lu.:sc:mbedCh.:rlllilll:d th..:IlIagnillluc ortl thermalgradientIIn(J..;r, t.:ady,.,I:Uc 1Iath;,'1I 1 i;!oor, unlessimpo rt ;! n!inan),'p.:"l' i1icla ...... 5.1ThermalGr:tdic .. t Thequantit y"f 11I.:alII tlwin!!" \llof an:IIIIHl I.1r circula r (l-.f!.aIIIK'or a\\'inushid callb.:oblaill cdfrolll lhccqu:t l iollgivenh,'low. cquulitll1is\'alidwhenIhethidncss ast ruClUrcisinrela t ionInit sdi :llllc lcr andisappli cabkto t lu;:Huealld Ihewin shieldof:t chimllcyfu rl.'lh.:nul\t crcdillpnlcti..:c, Therma !:.\ r" diclII'11\,';111... "lI.:c"hcidll 'I :,, (S whereq"'qunntit yof heat11,1\\',\\' Th!!proceJurcInadClptr,'r ,',li:l1,II;n;,:Ih,'Ih\I"III;1I;In.. :t"1,,,' ,,'10'\\il)("' ";, depends o n whether 11IS;IJIIlI.:,ITaIllll'ti,;ha' l h" lllll'\ ,!;"II' :::,' tk:dl\, ilhhdu (a) AtypicalIClIlpcrawro.!pr\llikad OI11IIl'"r ::,:., L',i [tt,(S.I).wc{':UIwri t..:d,' \\' 1I"'I":U,,.;h""h, '" w '"

it IS arid, C"and Ci arcthethermal conducti vitiesrespecti velyof bricklining, concreteand insulati onbetweentheli ningand shell,W/m ..c KI.. cocnicientof heattransmission from gasto inner surface of bricklining - KI ..+ KI.(refcrChart 5.1),W/sq.m"C. - coc/lkicnt of he.utransmissionbymdiationbetweenoutsidesurface of shelltotheatmosphere - 68W/sq. mlie K, -codlicicntofhellt(mnsfcrbyradiationbetweenoutsidesurface of lini ng andinsidesurface of shell- 0.085T.+ I.SJ,W/ sq.mDC K, - cocllicicntof hCllttransferbet \Veenoutside of liningttndinsidesurface of concrete shellwithventihllednir space "0.067T.+ 1.16, W/sq.m"c r 4 '" ar:II;lor whose value depends on effectiveness of ventilation in the air gap 'qcanbelakenas0.5 whenl\ventilalcdairspaceof a tleastlOO-mmunobstructedwidthis provided.Iftheairgapisnotventilated, 'q - 1.0andK.inthe aboveequationhastobe 58TALL CHIMNEYS '- 200 '" t-Z w ISO 100 . U "-"-w 8 z o I-0.:1.'11" ;1 h' Ih,h" 'I "k rill ....:)ll d\,.:;'.:: ins h: d:11111l'onn,'k will'''' :1 'unlil'l Telhi1cilltlI :0.:1,1.11:1\','1/ 1.'.f "II I Compressiy.: ill (I n11 01 rare' I r ,(fII:-- 1\ Ma i IllUll!o.:tllH\'Csi r..:'si n1: "Ill' n' l c "..I /'7.I Fe ThesenCl'minIheI'lfii ..:;t la"\\ cll:l 'illIhlo.:i r"lI\ lI t"n': l\ lialdil ..:,"" '1I a Pl'm, printcreinru r("clI lc ntSh\lllldh..:]l1< II'ldcdi ll,';ll'I ld, re": lill ll ,:\..:ar th..:lOp1'1' achimnq' ,the deadandwindlo:lIls1.';111Ill'Im\;1111 1 Ihe1t.' III Ilt: I.Il lI fe, 11" '''$GLI1bl'ro:l :lli \'l::I;' II .: nc.:il l lhi sregiont heIx: nlli ssihlc IInderIheo.:\ll11l1io..:\1dJ,,":!"fd... ad :lml\\i nd with lempcratureshouldber csl r ick , l lnllt:ltnOI Ill ;lII ),,,rmi ll ..: d\\"i; Ih' icnturyoulbh;mpo..:raturc.whichcvcI lower,unlessanambienttcmperat ureother than293Ki, ehoicnforT (ii)T,1!lotexceed31]K. 4.Determinethe log-meantemperat uredifTerenlial(LMTD) over thevoid. s. 6. A,'",' I.MTD "".":.,,' ::..-;(5 III(IJ ./.11 ",;,,). Usi nJ;Eq.(5.3) clkul ah:thequantit yor h::atnllwingintllIll..:void aftern:placi No)'N l:l11dLM 1'1)for U/f - T,). Determinethcme:!1ltelllpcratllr,;di !l"o.:rl'll lia lhetweenvoidandnmbiclll:lir. r. _ T,J - T" rn.)(5 . where coul dhe themaximum or 298K,whi ch:vcr lowcr. 7.UsingEq. (5.'0, quanti l Y IIf h:.:aiJ\owing (l iltthrough coner..:\.:wil (qr).U.,e'1;"r" r T .. - '/:,. I).CalclIl:llet hetlU:llllily"r healtithl'\'o..:n l ilato.:dout(,/.) of theal"Cl':,SvoiJby draft: rf. -, '/>1 -. fi r . 9,Calcu!;ltcmassair no\\"rt': pli rcdinthe\'rz! inthe dhimctcr of achimney\furic:; a lungit sil ci!!Jl lthensl agcwiscil11cgr:l1ionshould bedonetoarriveatitslateraldisplacement. Tll i:.aneccentricityinIhe actionofthe ;muthisp - S elkc!has 1(,helakl:nill1LIlIeel'untinthedcsij!nof a tallchimney. 5.8IllustrativeExamples ExAMPLE 5.1 The30Qmlllthi ckl.:oru.: n;lc Cif " "Jlil ll Ul)a,heln1;,]p. rauicnt of 38 C.Due t oo therIO: Hls,IheIll,Ud m1l11l :t11l1IheIl Il' :Lamilia.')of the arc4,0 ano120 N/ lllm2 011Ihl'In':W:II"l1 andwiLlJwan! fI'SI'lI..'Clivcly.With 0.3'i'0steelrei nforcementof whil'h72:Y"isplilcl"{lonI he(l !Jr.:,. ealculirleIhec(ltnbined verticalClllll:n;lcl"\ Wl' rh i\ht,n'nt!\'PI'Il' ill f" h 'I' lIll'IHI;.(,0Illlll.r,:!.'i. )I. rr [I };W(,per uC. Solutioll Leeward Side /(.;.33)0Helll.:':theneutralaxiswill[l e\\'ilhi lllh.:sc.;riOJIand l';lM':al iIof :'.3willapp[:, In '" 200/25.5 ""7.R4,k=O.1S.p... O. 003.,,//1- OJ(!35. r.,omb- (2 x5.33)[- 0.0235 + [ (2_.0,1,23:' )lO. :!S( t.ll -lt.;,) + O.!i( 1.0 - () .. I) ( [ .flI O.023S ly] .. 9.27Njmm2 ThisbthemaximulllC('llel"l'l el,ml[' lcs:.ive1fIi!/l/I\l(mJ Sille ;11);"7.t> 4 x 5.:n , 1.71) llenc ...ca:...:I)ti ila - 7. S.1....11 -: P ..... .... 13,\ h ----I I ._ .. . __._---EXAMrLE5.2 -:r......... ..U..;' ------_... _ -TEMPERATUREEFFECTS69 Evaluatethe :l reaof ventilationopenings required(oraJ1S-m1:111 brceehings) multi-fluechimneywithdetnilsusshowninfie.5.2.Eaehfluehas aIIS-mm,thij;k firebricklining (Cb :=1.1 5)and1S-mmthickmineralwoolinsulation(C,"O.06). Gasinletandoutlettem-peraturesineaehflucare160 "Cand151 "Crespectively andthegas exitvelocityis24 m/ so Temperature conditionsinsidetheaccessvoid should be such as to allow inspectionpersonnel toworkellieientlyonanyone of theflues whentheothertwofluesareoperatin:g.Design ambitntdry bulbtem'pcraturewhichwillnot severelyrestrictinspectionscheduling is18 "C. hisalso requiredtoascertainthetemperaturegradientacrosstheconcretesbellunder steady-state conditions when the ambient temperature is12 "C. C,.-1.7 W/ m C and barometric pressure ... 725mm of He. ...-:;::::..--Soll/ tioll DI>I'-' 4.31\1 .IJb .. :.: Du-4.3 +2(O.11S)-4.S3rn,/)p.4.4 I 5 m.D",-4.68m.D, ., 4.60Sm. Del ""14rn ,/)'0=14.8m,D, - 14.4m.FromChart5.1,Kle""45 andK,, " IO,andhenceK, ,,,, SS. T,/ =31JK.T" .,, 291K,T,,,. - J02K.T. - 291K,T, (mnx) .. 433K,T.(min)-430 K. "" 433 - 291=141:LlTrni" ""430 - 313 ""117;LMTO = 142 -117 In(142/ 117)- 129.1 Il ealtransmittedfromtwofluesto thevoidwillbe qg'"IO. II S0.0751- 0.322064 [ 2.x 175x I29. 1]141953 5S-x 4.Y+ -1:' .5-)( 4.415-'"0.06 x 4.60f+9 x 4.68 = 440760w Ikatoutof the chimney willbe [ .. 175 x (302-291 )] qr=- -- 0.40I1 --rfXi4A + 68 x14.8 + 9xT4-6041.6 0.02521- 239318W Healtobe ventilated, q, . ... 440760 - 239318 - 201442W Fmm2.2 x1O-1x 201442 x 291 Q,'125(313-291) Voidarca - 12.57sq.m andhence = 8.09 eu. m/s Velocityorventilatingairinvoid >=0.64m/s IEq. (5.13)) - 0.0341x 125 x(1 /302))-0.542mm,Hg ,: I ------------_.------------ TALL CHIMNEYS Corisidering equalareaof inktand outkl opening::, wchavefrOIllEq.(5.1-l1. 8.09"" 9.62' ,I , I iJ'.542j2 'fromwhich ,- , . ,I.c,:!:-;q.1ll To obtainthethermalgradielltacrossthe concreteunder steady-slate condit ionsw the ambient temperatureis2H5K,wc 111,ltalllhethreenues arcollcraling. Heat flowintothevoit! "'"Jx ...x175(431. 5 - T.)/O.3220M ""512 [( -I 3LS - Tt- ) Heat nowing out of thevoid "" 11')(175(Tr - 285)/O.025:::!7 '" :!1756('I',. - 2SS) Equating thetwo,wcobtainthevoidtemperature, r, "" K -PLATE 3 ... ----. ,.- ......

Lower portion of a chlmnevNTPC) ,.,. ,' . , " PLATE4 ._._._L __ ..6 FOUNDATIONS . . . 'Deing3.13011slender st ructure, achimney callsforconsiderable attentiontobepaid "tothe design ' of ilsfoundation.For instance.3.smallrotationof the footir}S'can serious con: sequences onthestructure'sstability.Hence,greatcareshouldbeexercisedinle5tirnating ., foundati on loads andinarrivingatthebearing capacityof the suppOrting medium. Inorder 10ccollomi... conchefoundationcost,sometimesthelowerportion of Qchimney shellisen-IMgcdintheformof 3.shellof revolutiontospreadtheloadoveralarger areaofsubsoil. Analysisof thi spaTlionof achimneyshellis;l150includedhere. 'J .. 6.1GeneralAspects Some asp:t l5 relevant tochimneyfoundationdesign.3fCdiscussedbelow. (8)Subsoil Characteristics . Thesearc :l scerlained rrom fieldinvestigat ion and laborat ory tests on soilsamples. The nature, cxtentandmanner of conducting such testsis considered 10 be outside the scope of thisbook. Howeve r,some.1.lient aspectsafementionedbelow. I.[Jeer bores coupledwithfieldandlaboratory teslsonsoilS:3mplesarerecommended in(\rd.:r10adcqu:1tcl yinvestigatet hesubstrata. 2.IntheC'asco rplate-loadtest s, careshouldbetakenininterprelingtestresults.The en!:.: ton capacitydueto :lspcetssuehas presenceof groundwater,testplate-lo r'lI1ndation-siz.eratio, etc.needto betaken into account . 3.Itisimportant10remember that afoundat ion?:lftca.nstresspossi bleweaksoillayers \ , - -; ,.- ' 72TALL CHIMNEYS existing atlowerlevelswhileilK'clle..:t,11: 1l1:\ynutb..: ill of loadte stsconducteds!1l:\I! 'siz,'plat es[M !n:Hlill!!, (b)Loads Achimneyfoundati ondesignisinl1l1cnn'JbyIhefollllwin!!major Iliad)... / DtQtJ l.oad Thisincludeslhcself.weightof a..:himnc)';1111.1and llrtH1PIll'f.l lI1Cdlll'lS,:.I t'n 's-,ories.pla!fo'rins.ctc. Wi"dLOQd Achimneyisawindstructure andhellcewindloadsshouldhee)..lim,i1CllwithC\lrelllCl';tre, Normally,windpressure asslipul alcdinIhe1',,11." ' ;1111nali,!!I;!1nllleus.: Jpal>! o[widdspeeds,etc,atthe1000:IIiollora ehimll':y :trl'\) ftcnnlltrC;lIlily'1\';lil:l lll.:: ,IInwc\.Cf, windtunnelstudiesont.ealelIuklcls mayllcIhX'l'));\ryhI c)o. t tlllatc\l in,I I,l;!lh in,':I)C5 whe reforces due 10aeruJynalllicinlcrferl' lKC Ihllllst rUl' tllrcs;lfC;ull it:il'aled or where lerrainfeatures arcabn(lrlllal. SeismicFJJecl This loadisimpofllLlllsin... eItha sa d rc..: t'Illthe,k)i!,!lIof a1;111 ;ll1 dit s foundation.Themanll cr,)f C1O lll1\:ll ill ):thelI illld,',. f'ildl I,)adsi)./>0(Fig.r..:n with!l.R 'C0S0 ,", iog linearlyacrosslhe shelldi:lIocter.Then, fromwhich. ., M -4 f Rcos 9 (fJa'cos 01 f!nda " R -=M/np:{j2 nndmaximumintensityof s(lilreaction[Ep.(1\.1)}willh.' q""4M/rra1 (1 _'14) The rcst of theanalysis suml1l:\risedillAppendixAand1'.'",11[ 1:;;If..:ia Tables 6.5and 6.6.Valuesgiveninthcsctabl es:lref\ ))'theri ghth:mJ of theraftwhere the reactionis::,wards..Corr..:spnnuillg"altho'sof dellcctiolls.momentsand shearsforthe handportion or araftwillbethesamehutoppositeinsign. T,\D\ [6.1T.lnLI6.2 --- - --- --- - -Pb"" ANNULARRAFT, I =1:::- r_ ANNULARRAFT0I, , I AXIALLOADpraDuTI MOMENTM_0 [[._-t;:ao ..,.. "'=::::::llo Wj_Vl...V2,2+VJ.Inf+ V"/InlJ we- 64DVsV&ViVs wi; qo"[IS.VI". V)+V"t InfJCos9 We192DVsV&fY7Vs Md=po2t12'6/-2'3 V2+ O85.:O_Y.4.(315+23 In tJ Mre64VGfT"V7Vs -=- -2061-63'- --'- - . - Cos9 M,iQ02E)V21.7.!'.ll'15V,,] . Mre192V&f3V,fVa M ti=.pa2 tS'8,2 _ 2'3V2_ 0S5. V3_ VI.(JoL.S +2-3InMte 6i.V&,2V,Vs =- -71-291-+-'---'- CesS MtiQa2 t 3V2,7V31-15YI.] Mte 192VG13 V,fVS Mri.:.0 , a_I= 0 Mrtiqo2 t3Y217.Yl.- - = - -3 1.1- '71- +-;'- '- -_.- SIn9 Mrte 192VGfV,fVs Od =po(",'_,') ri.=.qo[_72f2_8 V2+2.v"JC9 .2' Ore192VGfTVsos po(I_I') Ore:. Qti= qo[24l+8V2+2.V4] S'6-2 I f ate192VGTtYsIn ,222: V,= tnnV,-V,I"P ,P",, ''u' 2V,=5-L8"-2'52-296-81n Jl+8"InV,=-5-L60[I. "/(,,,'.I)-08In+3/n V,=(XlI:- 6- 82- 8)1' -21'65 I n' p + 21-650. ,.... ._00 o , I'.......!- I,1 - lrNC+M Nt-:;- --;:;-...."'.,.."'f;J00...r-.0'" '"'".....,..-oO.....N0 o o(:,00 , M0 - !1 -'N:::::,:..% I---T6.4 -- --T"""];'7 ", ANNULARRAFT -, -, MW'M td:.= Coe!1. pO 10 AX iALLOAD Cl ,a::D, MW 0' 400 ' 45, SO0' 550' 600'650'700-750'80I 0 r; s0'90 --30 -51. 0-22834- 16.9051- 12.1213- 6 1)7 - " . 701-1 68910133 4685- 726,(7 e21.0-)0 . . ,eo- 0 ,329- 26,751- 13- 711-14 161- $- 6110 - 5771- 2 l.400 ' 5063 -1555-5717 797 0'35 -0152 037-J .110- 23 , 8-16 73 -li'"'' - "161- 3'1.47-0-2072 G7652S{)7' 6630- " 0 z

t" r' I III W'

......il ,. il , I ,If , , 'I-, 11 80TALL CHI MNEYS , -{I\ RI .P jR a f=10-.J - Q D :::: __ __ __ .--L.. Fi!.1.6.3f iO. 6.4 (MBadDIILoad JII v;lri:rhJy,111I:Ju.:iI '.I ,t" r' ::11 1111:11'lllt],juad,;1It"'7nd,t ! :1\":, :t p,/11r 11: .111 (Iig.(,A). Thisloadiscunsidc rctlIII[wo '!: f,,1 alIuiJ"rmJlladwhi ch thc!:oiJpres-sure andthenadillcrcllEi;!1h.ad " f irl ll' usir),"" l li 'lll l' rP')I"I;,"1,)1'Ih.;f:, rl(""/'. [lll )III thesa meman tl er a !>c}lpla incuf,)r,If(lllran inSCl' .h (iii )of App.:ndixA. Tileelfeetof suchaJillcrcnti:rl1,);1;.1i ll,If ,l1in,l f :1:Id lu:rwc amethodisusedforHll alysis.ThedUII'lIwa rtll",uJ(I llalldcm"::l,al1'"n;.' 11"runite;rl'Ulll-fcrcnti al kngl h a nd it s 11I 01l1,:n t ;, h, IU!asect ioll a l ,.-' [1(1af.: :!il'cn ll y I Ill' I'" Eanhtiilk,ad .. f ., Momcntabout, -{ill '" f (II' ." Taking the of IJpwanJ .soil :11illllel1'IIh.:rp. .,1";1raha:- i/I;\lHI qlrespectively.itsalall)'In .... :l1;\ln(,-"fill;"... 1Iby (Ill - (6.4) (I' '' f/ I - - ,I _ ?:) Equatingtot al sui1lV:ll:lillllI,) l!l"l'al l hlillluad alld "bntlwir hl"lHlin;::1\1,1111I' ,- Ha: we get fnrt/l ami f/!whkh ar,'gh',uinrahk(,.7 wil h ,,1" ,1 , ;1\,'r)lI. Val ucsOrIhesesoi l .... ,If I'I:I(lfdi ll er,lltorall,l ;:11,'. 11,'11illT:lbk(ui. (b)Full HMI Often, acompletcraftispro\'idl'd of:t ";lIl1l\llarOH"::., 11,j' W.,'dlll ,'fillanah ""I!! sucharaftundert heabove1I11'llli()llnlI"reeIt'il\[,-(l1\dil il' !" :.,::!.'.l'p..:nJi .\,\allli theresultspresell leo;nTablesfl.9to6, 13.In I h.T ..'isasmall:\1l10tllllofova ,-, MO ::COt tl11x1() ," -SO0208 -75-2,059 3' 3!J3 -70- 5114o 70J -os-9120-))47 --60-11 774-7790 -ss-14079-12 ' 168 -50-16012-16279 - 45- 17 794- 20043 -' 0-19282-23 ' 438 -35-20-566- 26-'69 -30-21-612-29' 147 /or 0-900-85 TABLE 6.7 f-"!!.l ANNULARRAFT , .!... 0 BACKFILLLOAD 00'", 12: t2,\( 1 - B)(2-B-02)+ '::) { 3(1- rt) - 4(1\X.+ BHI- ff!,...6elO (1 }]Mrn :: a('-11) (1_02) - {2 (1-0')- 30: (I- n2)}} 6 ,)61 r6BI- 0:. A:: (oc.'-Il{a:.+I- 8t:'?/ ( rS:tl)(CC?1-I )} -5-I a3a 695 B::(C(+0)( 11cx.-9)+- a: (cc:+ 1)( trS:0loci) 1 . 6679'4381()'367 .2.1'"c::((.+0)( 3- cc.- - HoIl(d.+l)+8oC.ll -)'049727813'.0011\446 BP{O_c() " , A - 821,13 25512, 56115 12812019 -13 4&8-1' 8079 - SJ',17 04717'608'12'.165 q2:: 0-0:.) - 16551-7' 336562515 902205261861211-952 -23 295-12 9520; 56412 98520 ' 99322 9261904311 1,33 -27-644-18- 399-4,U78 ' 93219 ' 56124-85624 24218 - 72910-652 ",. o-eo0-750700 650-'"0-55O-SO0 - 450-40 J o c z o n ----="- -=- -.-.---'.. ... , t 4" o c z o z o \ .. - I' . 1;\ I' I , BBTALL CHIMNEYS aportion of suchIIfullraft!>u ppnrh:Jonrock,Ihenthenw.\imumintcnsily ofrock preSSure caDbeobtainedaftcrredistributionof pressures ;15showninAppendixA.Char!6.1can al so beusedfor (hispurpOse, . ., ", .>5 I . , ." 1 , ." 1. t t " ." .90 ,. . \5 ... ... ." .60 ." .so IlII' nIS arc obla;'h'dby;Idding thcmomenlvulll es ohlaiu('dI' ll I','aellIn;ld". 60 4t -,,--:--::---;---1 linearlyVaryingVertical.Pressure 7)EdgeMomentsAndShears .,. .E " '"~ oN 11' 'i'" u 8) FOR .. FOR 60 o sineAI+7.+f-) Cl 'si n (Y- f) lin= - p ,. . ..,-2a

I .1 lOOTALL CHIMNEYS "1,\lOll(,.:'.\)((".,/11,1.) [ '. Ng ::;-'27f Shf cr;0L..-____-L.._ _ ... --- -r d6 v .E:!... I Fi g.6,9 ,,---_.---FOUNDATIONS101 TheabMe equations arc applicable 10..hYrc'rboloidandsimilOlrequationsfor , , , a : conical lohdlwinhavetheform givenbelow. li ..- ,'f. [1.2(N,- N.)- .t,;j'c,,;. -0.2N,)] Va lues of N. andN. (orN.)as obtainedfrommcmbmnc nnaly:;isarcsubstitutedinthe above 10yieldthe cd!;cdisplacement androtalion.Relevantexpressions for each lond fl)faconicalshellarcgiveninTable6. 19.Inthecase of ahypcrboloid,these arccumbersome;lIldhencearcpresentedinTablc6.20 wilhthehelpof coeffici-entsir ,jr.etc.Thesecoefficient sha vebeencva.l uah:d fo rara ngeofs hell -geometryparamc-h.:rsandtheir "alucs presentedinTa bles6.2 1 106.25fClfreadylIse inndesignoffi ce. (c) In:llling Fo rashellsu\:ljcclcJ10symmetrical rorcC'sandmoments (Fig.6.10). shear forceat any locati onisbytheequation, 16) Q.,...- C, ( ->" sin(.\yH ),)(6.10) For aC(lncl:ICaboveequationswillbe :lnt! . .........;.... ......------------..--.,. ... R/, 1.2-0.1790-0. 1111-0.0(;91-0.0400 - 0, 122')_ O. 12t)()-(l, I IU, \.9(81.S421.712 1.3-0.1191- 0.0794- 0.0514- 0.OJ I5- 0. 1556- U, J.l 5(,-0. 13);5- 0, 13.1&2.4222.2742. 1(,1 1.4-0.0892-0.061.5-O.()412- t) ,026U- U. 16IS- U.I .US-- 0. 14 5!>- 11. 14022,)(52 2.7322. SI:iS t.S-0.0709-O.OSOO-0.0343- 0.0221- 0. 1M2- 0. 1559:U04.1.375J .lUll:\.037 1.6-0.0584- 0. 0419- 0,0292- O.OI '>!- n 11>-1(,- II . H75- 0. 1'6.IZ.l5. 711 2.1- 0.0291-0.021 8- O.ol5:1- 0.1)107 - n. l\hS" . 1.115- n. I 2i1\/.!('7 (d:O!6.355 2.2- 0.0261-0.0197- 0.0143- U. I Jl'1S.Z557.10.1 2.4- 0. 0214-0.0163-0.011 9 !I. I- ll.1 :>'.-1.\o. ..!I.II7!'1.51\7'/.{l.l tS.-I.2.1 2.' -0.0 196-0.0149- 0.010')- O.U075 ' 11. 11(,7- U.IIJ'l1\.11010.-1 5'1.:;399. 17J .. _:}:: ... _- - ----'--"--FOUNDATIONS103 TABLE6.2) VALUESOfCOErnCIENTS/"/.,J. - --_ ---------/,/./ , 6X' " ,.' 80' ...,,-1r.RO' .,' 72'76'80' _. -.-I ll" 1.20.7670.8)00.8820.9:!4- 0.21181- 0.2)91-0.2032-0. 1780 0.674 0,49, 0.3.12 0.24' 1.31.277 1.3'3' 1.416 1,46'-0.2"9-0.2233-0. 1981-0.1812.0.9110.686 0.'06 0.)12 1.4Ui281.')18 1.9922.050-0.2361-0.2118-0. 193)- 0.1800l.1160.9010.6820.5{9 I.S2.4202.5252.6122.679- 0.2210-0.2018- 0.1811- 0.17641.4651. 1)8 0.8110.(8) 1. 63.0523. 17l3.2733.)50-0.2084-0.1926-0. 1804-0.17161.7801.3961.0910.864 1.73.7153..'1643.9784.065-0. 1974-0. 1840-0. 1137-0.16622. 1171.6741,3231.061 I. ,,)A)') 4.5%4.1254.823_ 0. 1875-0. 1760-0. 1671-0. 16062.418,1.972I.m1.273 L') ' .3105.515'-61$-0. 1787-0.1685- 0. 1607-0.1,50 2.8622.2891.8371.>00 2.0 Cdl0.4-126 0.4314S.Sl S4.?S84. 1S9 3. 714-0.3262-0.39S5-O.SOSl-0.7037 -----'0' TALL CHlMN[YS T ,\\l U6.:!5 COl. I ""U ".'; i" i , .i, i, i,i, ----.. -, ,,' 72 '7..SW IJ)\" " 71, , 7h'SU" Rill 1.20.1200. 145O.IXSn.2SJo: ItHiS0.4')4 n.(, I;:

. tU N. - I\. ::IS- (]:'.M.. 1.30.251 O.3(J.\lUHS1l ..U,(.(, I11.); , ., 117(. " nr. - 11"s ll I.' 0.41110.507 u.6'l I:I-U:,..13lI.u5\ o."H L.1111..1111U.h':S_1l. 7M - 0.'.112- 1.35-1 U0.6180.:'49 0.957l .n.\0.1-1:!t\.lN'}1.I .IS1 hUll(l.'1!7.. 1. BI- 1.4_,5- ::.\101l I.' 0.846 1,0251.310IUHJ0.')S6 1.7SS- UU'J-1.5.\:; -2.737 1.71.100 1.333 UO)2.:m11.873l .nS8U5:!l .liS) - 2.0(}{l -3 SS9 1. 3781.6112.13-1 ?;. 911n.'I;.1Ll t9I 1':: ')\. '1'11- ': .11(, 7 . ! ..'ill(, _ _ -1.-159 I . 1.6192.036 2.61lU.1. 621u.'KiS1.11(1 1..1' 1'" .. ::.51"'.1 (I.U-- .t'IIlU.. n.l 2.92.0022 .427 3.100 ,UI !)1.11111I. 21-1 >.lIlt \\.(. \I/,5,)l, . .t7'l .U 2,3462.1$443.M3 5J.().12 :.i1') \. :(,(, - SASH - ' .2.22."7113. 2864.20U 1.1151L(' : ,) 2.::>5 ...1.1)(,;.... 1..'1.\(1- 10 ..\(1s p; (i r.!(-:-:' - 1 - 9) (1 ';- ::!sin:!(.'.-18):- 2cos plsin(1- ('1 +8) (e){""0 , I ):.,',.""(:11: P- 9) - :::CI'S .. ' sillIHsin '? r- l e -!,(9 - ::0 _ PI (t .;.2 9) - +{3:!?+sin '1 /1';228: + 2 n's 9(sio11-1-2cosI_

0-5 0-' OJ --0' . O."' )3 np' 0' .. 'OJ0507 11 ." 0, "'-18 C 16 0, 1' 0 120 0. ... 100 .t'--L"-t'--90 ' ,0 t--.. -85 -' \ '\ "-'-..

I"'-........ ,., \ "--........\ I'---70 i'---,., '5 6S '\ "- t-.. Chart 7.5Annular soetion With one openi ng no ) . .... c '" ...,.; 1< J--,. .. L--. ,.. H I..- -: 0' --o -0' 60 5 0_ : - o! .. . 1. 5 --0'. ".0 o -: 17 0-19-10 fl- 30 }J- a o o 1-1 --'--- -- 1: cpO ----ELASTICDES1N12 G1 .

' -5 ,/V H \ .1 '/ V --V C ...---..... ,.. (, y ",-V V ,-. M/W ,_, V....-te= C W/,.t( I-p) 0;-::V"'-- ,iJl::" / V 1< ...-./,....; 1-1VI/' VV H ,-, I? V V ,., 1/ ...--V .eO H V V' V H V . 70 0-' r;:: V .o! tO B l,...o-.&0 P .,.., 0 ' .... __ .7 . < 0, C - 0' 0< 0 0-5 05 35 1>4 ., -F 30 0, 0' .7.5 01 ." 0-1 ,0' 05 07 O' ." 15 ."." 10 0.113= 15 (/1 -165 }.J= 15 04 I 120

0' ....:: - 100 0& 0" , 0 I on Kt--=: 0< 1-0 r-.. f'.. t---. ID t-,7S 11 1' J"----t-t'-- 65 f-...cpO 1-4 I" -...... r-.. '5 Chart7.6Annularsection wi thoutopenings ,--- . , , l' I I ., II , 11 ;I I , t ! Ii , , , . ; ' I. I , . , I 122.TALLCHIMNEYS

r+' j 5., ... .-., ' 0 0,., 3 S 0' 0 .., np0 . '0, . , ." Il ."." ." .,. D' -I'!- 30 '60 }.l- 20 I. 0.. E 120 .!::. 0"1< 0"

t>1 . 0.' s ,,0 1'- ......., .. .. . -,.0 1,\ 70 I--'2 ,2 "" 1'-...... r---r..... q> ,. I'-. t' 5 ," 1 I I Chnu7. 13Ann ula rsoction withtwo.-.... --- ------1 ---------- - ------ELASTICDESIGN129 IvI(v ..... vv v-I.--' I'5 ...- f"'!'; C V

V V 1"3 l e' C,wj ,.I('-p) ./ V I.--' V ,-" V V.,.....Vl-'"b V I-' ./ .... "vI/' I,., V V VVVV ..... '/"" 1/ V V-V-I--- . jl

[:::v V I-' V III 0 ' 3= 0-' .- , : 1 k4i -11. npo., OJ0507 00 .,. ,0"1: 11 lis' W&-=30: = 25 IX E

0' 0.-

---Ill.0.' 0" t'--, I C "-

-.... l"-t-111> . ;., " "--Chart7.14Annular sectionwithtwo openmgs , , I.

j , 1 iI Li III ; I H' I , , I , If I - I130TAll CHIMNEYS...,. ,,< 0, 0' np.0'0' 01.. 0.070. a, 2&2_ --.,-L(.. .1.0 -." n

r . \ 1 - '" .., . .., ' 0 0. 7 0, ., 0' ." 20 30 q"' 50 ... I ' ", ju30 0' 90 0" .., .., Chart 7.15Anllular section wllhtwo openin05 JE ..) . ; 0' 19 06 I+."'" '..........-r-.. 15 ,.,NI"' Izt I

; t.-..:il:1J.. 5Chart 7.16Annular section with three equal openings - .-- - _.c" -T " "t,CHIMNEYS I 16, f'" '5.. V V V C V ".. V V V V

V V V v. =M/,W b':' ...... "J 1: r.t( '..:: p) V /' V.......-.......-I'!""

,/ t:::: ...... V V ..... ..... . ,., 'r t/.VV V t;:.

...... 1' ,0 ".

V ....... t - 1"I-'" --.l: 1&( ... b-s --Q 5Q COl D' E:: I "' 51 lO'4 , . OJ P22I--= I--itj1f"lJ I) " ." 1 13-20

rll40 "160 :::::I: -06 I4=: f -ID" I COl92 t--

,1,'r:"...,...... ,,-r-. : 175 Iol'" -t--r---. rpo Jj '" r-.. --- --- . Chart 7. 17Annulnrsect ionwcththreeequal openings I ELASTICO'ESIGN133 (onerelcsl ressillthe e"tremefihret'anhemuchlarperthanIha\atIhcccnlrcof shell n..:,s.Itshownchewhcrc1'thatIh..:maximumisthengiv(;nj.{nl'l:\) "'.r. [I...---- _.1.,..,_7 ] ,, .('.l r cnsf'1(t'os/Jthick-,... Theusc(. fTable7.1 f,' ranal)'s ing.withdirf..:rcn(numhcrofopeningsisexplained bdUlv. XIIO,Wllillg,\ Form (lSIofitsho:i1; hl,achi mneyisfreefr ll 1l1openings.Insuchacase{J"" " .J O... O :wd\';t lucsIll' c(lcllicicnlCUfC ploltcuinChart7. 1.Norma ll y,openingsneed10beprov.i-clcdinIhl'1'11\'Crportionofachimneywheret herlr1',11;0isgenerallylessthan1. 0nnd lu!m:cfo rIl leloC caS\:stheIImximumvalueof elr inthecha rt si3 limited10J .5.Intheupper r\':!chcseithertherearcnoopeningsorelse there clluld be ano pcningsubtending ahalf angle 15....Sinn'athigherIcvdsthe (',Irratioinpract iC\:canapproach2.5,charts for these cases an:IIr;l\... nror ('Ir... aluestill102.8. 0111'Opellillg callbeanal ysedby O.c 11 "(I.Thcgo ... erni ngcriterionisthat'the wind direct ionwill coincidewitho rbediamctric;J.l\y tothelinedrawnfromthe chi mneycentretothece nTre(lf t heoreningwit hanhalf anglefJ.Theworstcaseisconsi. dccnt whilephl ttingC... alueslli ... eninCharls7.2107.5. TU'II Oppfl.liteO,wllillg.f thiscase canbeobtainedbyputting0-0. \';llu('sarcphllledinCharts7.6to7. 15. TwoEqllal O{,cllillgS (notlocateddiametricallyoppositc) Cvalues for arangeof fJAndp .. , Theana lysisfnrthi s casc basedon ajustifiable assumpti on that theser.:tion issymmetrical withrefcrcn..:e10tht!winddirect ion.Four cases,4A104D (asgiveninTable7. 1).needto helonsidered.Incases4Aand48 , windblows in adirect ion whi eh theanglebetween the openings. Inl'ascs4Cand4Dwind isal ongaline j oini ngthcchimncycentretothecentre lineof onc of theopeningsor directl y away fro m il. The second openingisnow not symmetri C:ltwi threference10thewi nddi rectionandhencero rana lysispurposes,t hi sopeningisre-placeJbyt\\"oopenings eachof half its andposit ioned symmetri callyon eithersi de of tl l;.'winda"i)] = 75. 583m" hp '"18.657m4 J,q""2S[2.;69 +sin si n 40"_20")1].. 1.865mt h:Jl ""IJpq - 2: {cos60_ cos -10 - 4(":0530"+eo$20") (sin20- sin300)/2.269J = 1.4S0m4 SO.,25[ '.300(Y-300).rr(si n20 - sin30) ] Ir- sm Y- SIn- 2.269 xISO 5[,;ny- 0.5+ (y- 300)1822.889J -5[3) _.S lq - cosIco:; ."2.269 :-: 180 = 5[0.866 025 - co, y - (y - 300)171.994J Fo r a.windangleof68 andusing Eq . :11.34SJ - 9.79k.N/sq.m Total shear slress "" /os -if(})" 213.66+1).79., ""10(10.. 0.2-4 ! 8 LIMITSTATEDESIGN InachimneyshellthesteeltensilestressI:unincreaserapidlywithamallincreasesinthe O\'cTlUrninFml)I1lCnt.Since themomentiscausedbywindload.the magnitudeofwhichis :lva ria blequ,tl lIityanddiOieulttopredictaccuratel y,itbecomesimportanttocheckthe :;.lrl1ctufc'SstrengthunderlimitSlate conditions.Suchananalysisisalsorequired10ensure aconsistent or safetythroughoutthehei ghlof achimney structure. 8.1Part hi ILoadFactors Forthelimitstaleof collapse, some codesrecommendthe samepartial loadfactorforboth deadandwind1'):1(]5.This maynotbeappropriate sincewhilethereisavirtualcertainty regardingthemnf!niludeof dcatlloads. thereisuncertain variabilityin respectof wind loads. ItmayIhcrefll lt:beadvis:lb/c 10confirmthcstructural adequacyfor load combinations with partialloadfactors ,lSgivenbelow: J.1.5DL!1.5LL ::!.0.9 DL +1.4WL J . I.::!(DL + LL+WL) "f h..:aboveloadfactorsan; givenforguidanl'c,butinmeas whereabnormnlwind wlIJiliollSprcvailitwouldbeadvisableto undertakeastatisticalanalysisofwindrecords .1 lHlthenprl'di\ttheloadfaclortoadoptforwindtoads.Degree of riskt.:Ouplcdwiththe corresponding costpenalty willplayarolein arriving atthefinaldecision.Thefollowing twolimitSI.ltcsarcdiscussedbelow! ISCU. 142TAll CHIMNEYS I.Limitstateof2,Limitst:ttc of servi ceahili ty 8.2LimitStateofColI'IJlsc As nlclltionCll :Ibow, est illlnlcuI,uath;afactl,rc,1toarrive011t ri,'11Ui 111:11-

0, I-Vi--I-'"

-V !----,0!--05V-I-. V-V I-'" f-' I--k-r=:: I.--' 04 .',fy\' 250N/m, I.--' I.. p-I--0 0' n= 30 I?----L I.' 0)J= 0, ..L . 1 , . '02 .. , ." 141, ." .,. '0 .,. 'la .., IA -CV ---Chart 8,5Annut/lr sectionwith ono opening .\. , f \ ~ .Mu/Wu Wu:k"ck(I-p)r.t n ,.7 I ,.. I " J , 5 :-"1 ,., I1 I"S , 3 V ,2 :; IV/ to.1, ~:j /1/ "0 V /V v./ gj ;/ v..v ././ o /' .--7 1 I....)...... V V 05 V....... .. , 03 0" .., ... .,. 4::", \ -. / . 01 ,., / '/ .. ! 11 J 1/ -: 1/ ~ v / / ./ :. , / / ./ / V ././ / Y V V ,.1 V V ,,; ./ V ./ ./ ./ ./ V V V :.> V I---' " V " ./ Y ./ ----./ Iv V V ". k ): . . ." Ia ." .,. '0 q, ~I I , ; / > I ~ , r .i V , / ./ ./ , V , . , ." . . '7 ~ :1 . 1/ 'I ,.. V 1 Y., . V !oS V \. ./ ~,., V " ./ '3 ./ ./ ,., ./. ./ '., V ,.. .A . .. , .., ..... 07 0. 0, , : Iyl: 2'fIJNlmm2 0" rl= 15 0'3 p= 15 .., 3 .", ." '50 . Chart 8,6Annular sect ion wIth two openings I , " , " , I ) ~ ! ,~..... -15ZTALL CHIMNEYS 04 I'-. 0' 0'7 . 02 '0' ' 0 .. . ." 0 0 , .fy\' 2'JJN/mm2 0 o- 20 1 so jJ= o C 10 11U,30.)L. 38./..'1.46SO q ~ , ~ 1.' y 0' ~ " 0' 0 0' " "0 ) ". O' 2 02 0' 1014 .,. ." .,. '0 .,. q. Chart8,8Annular sec ti on' thWIt wo openings ...... 1' 0 0 5 ...-0' 01 . 0 ' os fyt'250NI2 Imm0- 4 fl=20 ~}.l=20 ... 0) 154TALLCHIMNEYS ~ ~illu '0:' "0 I I' )' ,.. ,., / V V: 2" Mul Wu Wu: kfCk(1-p)r.t.!'I ,., ,.. f V V-,., , 1 k::: ,., V V-V-,.. V ... ~ // / V t:::: V '515 V /' . I/ / V-,. , I , 11 11 V VV-I-" 1// k:::~1 J ,.] I1V ,[v 1/ V V-I-" V-I-V I , I .,~ VV& V V-/ V- V f-" ~ le::::I:::::: ...I) h' I . I ~ 11 V V V , ~ , V V V V V V, . 0 1' 0 V1/ V V ? /' 1--' !/ V[...-' '1/ I-' .... 0' 0' 61 V V V-V ~ ~ V V V /' 1-0, . 0 ' V V V V V-V I-V !;-:' k-V-.? .... 0, 0,' ~ V-V-I-' V- I--0. -~ 0' V l' ) 0 \ I--' O S " ~ 4 y . 0' ---:: tyt'29JN/mm2 0" -...-dJ : 2 5 03 n ~ - 0" -1.S 0 --j . J . ~ 15 i"'" . ' O 2 , , 0" .. , ... "014 ."."." 30 ." '3' . "." 50 q. Chart 8.9Annularsecti onwi tht WI.>openi ngs LIMIT STATEDESIGN 15' ~ ~iJju .0 I IT / 10 / . ,. , / ./ '9 21'oMu/Wu. V WU:k"ck(l-p),+n ,., "8 V V ~ :T ,. , VV 1/ ,., / ./ ... / / H 1/ ./ / / ./ ,., -;f1 / 1/ ",-,. 5 ./ ./ ,. , /..,Y , ",-,. , / V-V ,. ) ,/ / V 17 V-' ., . / .v ./ V-,., )' ,., / c,.;. ,./ / /' ". .... I .0' t' //' V . ,.'t . ."'; 0' V/ 08 V V / V V V ' Vi--/ L.-0 ' /V ., /' V I.--/' ;-.-" .-" 0.'V V . . -..-0' /' V ..... ;-;-0, 0 -' Vfyt=415N/mm2 0" . 0" f-0 0 " fl= 25r, . ] jJ.-= I 50 0' ' 0' 08 ." .,. . 10 ." .,. -'2' .,. "0 ." ."." so Q.1 60 q. Chart 8 .24Annultlrsecti onwitht woopenings Ii , 170TALLCHIMNEYS I' Char I8 2Ss:(':'!OI1wit!tp,i( ; ~ ,.g ,., , ' 6 , 5 ,.) ,., ,0 '7 ., '5 . ) ., ,.,Hi-IJd ,., QI09 V 0"V vV'V 0-7l,.-Ooili:- ra nd"1llincll L' It.... Norm;dl yfur chimneys,Rcisultra-cri ticalanllth i"pcrmih I, )heb:. ,,-dOilantit;!!Iho: excitationispl: ril1di c.\Vhen1(j-,'tl j'.:rnih,.d .nrit:Llipu:111.111h'f\-'I' PI1 '':11,'il1;'. small , this casedoc:;1Iv1gencrallyeOlltnlilk,igll .Il o\\,('\'(,:r,amcllwd()r:l1Ialy!>i:- f,ll'the lallercasc al${)i!>Ill;",'1J\1:asonryLiner ._-- ----Wcighlofthc lin(:fmateri :!. 11.MlI.sonry Thc::seincludevariousof bdcks-ena1neering,moler,acid resistini. firebricks, etc. i$C'l(ricdbythelinerIUelf. There are two$ub-c1assiR':3. tions a1given below. Liningwithoutnnylateral e.g. sel{suppofling brickwork 2 . Metal Mil dsteel,stainlessstceland ot her alloys Liningisindependent,bUI),Concrelecast insituor prOCllllt lateral restraints arcprovided to cnftlre c.!.!. 4.Plast icsORP and GRP Liner verticalsupportsIII 11. numberorintefmediate pointsa\onsitsheight,e.g. Ixickworksupportedon corbels Liner /5bondedtotheshell and:1.0part of the shellwithsupport, e.;., co.:\tinss ,.Coatinl!Lead, elllss, etc. ..".Masonry isthemostpopular conventiollall illerma terial.Independentlysupportcdmasonry isgenerall ymoreexpensive and C:lnprove\lI1aeccptablcinatallchimney,particularlywhen , I. ,I!t ." -,' ., . I , , , ( I, I ' I: ! , , I ', ,",:. .- . "',' , .'' -198TALL CHIMNEYS in-ahighseismic-riskarea.t\masonry liner shoulJhaveeither;1n iml'lcrmcabh:t ins membrane to pl"cvcn'cg.rcssof OuegasesOf, ;lIlcrnalivcly.:\\,cllIilat\'tIair gar10' .$uQhpermea.ting gasesoulof n. The choice of aparticularIYI'\(.'()f IIJ:1sonryliner ucpcrulsla rgely IlI\thl' operating h:m tureand chcmiculcompositionof nUl' Thefollowingisabroad l!uiJdincforcltOI asuitnblc tyre of n1:lS0llryli ne r whellthenUl'!!aseshave corrosive "... ,',.. I.Ddllw 1" 'C 1I7S". 800C 3.:wt)"'r1111)C --------- -(I) trnglnteriltu-1Jr1d;lining brid,s M;mr faclorsha\'e l\llw cnllsi,lcrctlto l\I;lkc.1 choice.Often, mnkr;In' preferred Fire'.rick.lire"rid.IlIaybe ir he:ty)'dtel,,;,',,1 "liad; ,mtic'I';tlt'lI Dense engineeringbricks can1>0.;usedtof011llalinerinthetemperaturerangeI SO ': where chemical att:lckisnotprescllt.Stlchbricks cannolwithstandthermalShOI,:k. (11)AddrtSlsting IJrkkl,.jnin:: Such brickswithsl:tndtilltypeor chcmi.;al;tl!a.;klIormatly by a.hiHlllly Thesebricks arcparlkularly wJvuntageollswhenthetcmpl'r:t!un: espl.'':II:.IhIhI.'COl oustybelow17S'C.ThcyhavelimileJr111111rn.JlI top.acircumfl)f:1chi IlIlK'Y,ligh"Iing C'tllldut.'h)1"Ssllll ul J\10.:adcilU:IIL'1ypro tcetedfromdll'mi,-:tIby:l1'1'!yin!! ;IIc:nlC,);l l in!!(Irhy0lh,'r suitahk\llC;tIlS, - -+---" \ :'-1'-"'1.. ! ______.J.. ___________________________________ ____________............ACCESSORIES209 11.3AviationWarning Lights : .... -Aviationw: Lrninglightsarcprovidedcvcnduring construction once thechimoeyrcachesn heightIll' ahout45m nbovc grade.UOlhlempornry aswcllnspermanentprovisionsshould meetthe of theCivilAviat ionDepartment. Theselights shouldberedincolour andbe either of filamentor neoll type,the I:uterbeinggenerallymorereliable.Theyshould beofintensi ty (about100lux) sol hatthcyarc conspicuousconsideringtheback groundilluminatiol1levelagainstwhichtheywillbeviewed,Suchlightscanhaveaflasher unitandilisprefcmbletoincorporateannutomatlc nlllrm whi chwillbeactuated whcnthescli ghtsarcon spare_Cablesandconduitsleadingtotheselightsshouldsafely withstandcontinuous exposure 10thetemperatureexperiencedby concreteinwhichthey arc embedded. Daymarkinssarcprovidedbypaintingthechimneyincontrasting colour bands for at lo:a51 thetoponc-thirdof itsheigh!.Suchbands shouldnotbetoonarrownortoobroad andcouldrnngefrom0.75 to3mwiththeoutcr bandsin thedarker colour,Thepaint used forsuchbandsshould be add-rcsistantand should safelywithstand the temperature expceted at thc chimneytop. 11.4Lnddcr t\laddo:risprovidedfor accessup tothetopof achimney_ It shouldbeofslurdy const ruc-t ion.prdl' rahlywithnon-sliptyperungs,andhavcasufetycage.Atowerladdersafety d..:vieeinIh..:rorm of agalvanisedraitcarrieris nl sorecommendcdnndthe ladder shouldbe connect..:dtoIhcconcrete shellbynon-corros iveinsertsandbolts.Atypical cross-section of ai,;slwwninFig.11.3. 11.5Clean-out aDdAccessDoor Asuitable door shouldbeprovidedat thebottolll .of nchimney. Whcnamelalliner isused,theopeningmeantfor an o.ccessdoor isinilially 'mndelarge 10serve as an accessforliner canswhich haveto betransported 10thechimney centre forerection. Twopairsof clean-outdoorsarc providedinthe shellandlining for access into achimney andtocleanthe soothopper.These doors shouldbe suitably tre:ucd in order to be heat and acid-resistant andshouldbe of gas-tightconstru.eti on.Suchdoors shouldbeprovidedwitha btch:tll J:-. ho\l ldmmn:dly!:le1 houl extendcompletelyaroundthecircumfercnce.Similarly,addition;l!verlie:!1rci nfor.cemcr shouldbeprovidedoneil hersideoftheopeningandeaehband(If!'>ll'c1 b placed within n di sl;mcenolC;(ccl'llingonc-anJ-a-half timestheshell thiekm' !'>!'>, 11.7l\lounting forLiftingi\latcrials AdequatearWl1gementsmlistheIlladeforliftingmaterialswhichmayhe1"uld1Jl'1',11' ;1wl"crl'):ld" hid.\\ il :iud: ;,\, anticipate(110h..: Ihc':','() 1llH:li nl,'H:lI1n:,\ : ; 1\,\\'1::111"r 1I1al,''';,: ,..:'[:011"1111IIU y1I :I\'l'1 support thewl'ighl"I' It)rIh..:n..:.x1tli :,:i ll'rI'I:ilf'or1l1\',:; ,' during \':l qlll ;! audth is1" 1:11\' T;' !llI: ':' 1,, ",:,: ,'"" I;:' ,h..:wC' i/h:,.1Ih..:bu. I;'j: :;' :ll1h,',oil arcof prccas Iconstrueli"l!.th' u:dlup\:ra li o ll s";'''l1 ll1 inarcgul:lr!,alt emillon.krI{'I(,blair staggeredlap. Reinforcementfor thi.: ,sha l"tshuul dh ...illIhllexcl.'cdi u::1.5IIIfur 3 6IIIforho ri zolltalbars lilr !.: :ISCllrVcr l!!;;! 1 barsom::pllsi l i' lIl l.' dwi l ht hehelp "I templalcs' fhtet!tqthe,formsandIhe}'nolprojl' cl1\\(\far:lh(lwtIll"k \'t;1 atwh concrete "'lI:'lli,':.h;11':doll JI1:'11 ,,,'1\.1'..:1111;: ./\ ' slipforming.,thesehars;'1r2 slrai;; hlcl1ed,HI Iwlli !.'c, >!1Cn; lci:. ):1\.','11 " "1""\\"f itis10\I seh;l r;;a ndt hal,,,,, illmi l,1shod :.illc.: o.: l!il'h-YIl-ldI, 10bebriUleandme morcdillic.:ull10sl raighh:1101\1 " 12.3Forrnwork Formworkisallact ivit y,o, h.:r,hancl lll ercling,whidl ulnlarc11 Theformerhave alowerini tialbillitisdi llicllll10t hej;:Hld formoperation andas:l T\"sult .hydl"nlll ic .ar.;prcfe rrc,LSlid,:If..:f.:dradial linesralher thanthr,mghaCOHl lllll llein.:t1lllfa\' lltialf--,,\kr.J ;ll'k", USt placed about2111'a pa rtand"arc' (ksi[w..: dwithampk I\"serv..: (b)Sliporm Slipformsarccont inuouslymovingfomb.COll1paredtoajUlllpr(\1' m,aslipformyk

'" a " y d , j I ___ PLATE7 . ....... SlIpformbeinginstalled for placingconcrete during,Upforming " ....: ," " .,' .. ., I ", I 'h.' I I ! I ., "I ft , -'(,'\,! '. ., '''''" . ~ .. "'. .~ " .. ,.. j ~ . , , . -.. .. t . ~.. ~1 . r \1 '. 'i'/,"lPfI,. - _____ _"",. "f',,"", " ___ _ .___ _. . _ _. - , _... -CONSTRUCTION219 monolithicconcretestem and enablesspeedier construction.Ontheotherhand,ithasa hiS her initial cost, requires more equipment and callsfor arrangement!> tobe madefor round. the-clock and supervision.Onthe whole,nslipformgenerallyworksouttobe moreeconomicalascomparedtoa jumpform.butthissaving canberClldil y lost due topoor conslnlclionplanning Offaultymaterialdeliveryschedul ing. Formshullers :lfeusuall y positionedwithataper-widthatbottombeingabout1(). 12 mmmorcthan thatalthe top-i nordcrto reduce drag.The rale of slip commonlyadopted forconstructi on isJ 50250 mm/h.thoughhighersliprateshavebeen used. The rate orstipisextremelyimportantanditdepends.among olher things,onthe t ype or cement used.ambienttemperature.etc. Asliprale slc, wer thantheoptimumwillinvari ably resultin e:(cessive dr"g on the rorms and damage toconcret e.Toohi gh nslipratcwillresultinweak concretebeing exposcdatthe hottom or rorms. Forlllworkamiitl'supporting assembly shouldbecarerullydesignedfor the likelysuper-loads.pressurcrromweteOllcrelcandwindloadsusing normal concepts ofstructural dcsign. Thevalueofsupcrload10beconsideredforthe design of platrormswoulddependonthe .planrOrstorageof mate ri als.lihly londsduetomovementofmcnnndmaterials.crane etc.Theseneedto beworkedout foreachproject. Thentngni tudeof lateralpressureon formsfrom\Vetconcrete dependsonmanyfaclors. suchasconcreteconsistency.ambienttemperature.rate of concreting. degreeofvi bration. etc.nndvariousempi ricalformulaehavebe.:nsuggestedtopredict tbispressure.Results varywiddyandIhereisaneedforfurtherstudytoarriveatsuitableguidelines.Pending resultsfr omfurtherresearchwork.the commonlyadoptedlateralpressure diagramforthe desigllofforml'is showninFig.12. 1.whereIVis theweightoffreshconcrete i llN/eu m. LOP or,"ORM 8 (. . _. . . __. . . _- .. - o o , [80"0101,"ORM ..-

Fig. 12.1latoral prossuro diagram For amaximum r-:5ull"nl pressure of8800 N/m on the formwork. the design fricti onal drag ma).betakenasll 7350N/ m forboardedti mberformworkand4000N/ m forawater-ti ght. surfa-:etrcatedformrn,ce.. Irll "l' I'll , I 1'1 , , '" . " I11, "I'1 II,I !.II ,I ,I -- -----.-

220TAlL CHIMN( YS 12.4Lining J:orliningworkthen:arcno':SI:II1I; , h..:.\p rol'c\luf\'sIhal:11, :L,"\"q'h: d.( below arcl>ro:uJguidelines \halshouldbeli lllll Wl.: J CI'II , lrtll"t ioH\IfallJ liners,whi charcthecommonl y :ldopkJIllall,!ria]sfprlining\\'l'r\.. , (a) LNiasonryLiding Firebric ks and acid-resistinghricksshl)Uldheof first -gradeIllIalit ywilhaminimumc ingstrengthof 200kt;/sq cm. Theyshouldhaveinlo.::gralkeys .... ldsll\\1I1.1be,Lt 2.'it thicknearhrccchings.""ltadiaijointsinbri ckworkshouldb,'brok":lIinl' :tehC(lllfM::1 ,sbouldbe finishedfair-facedontheinside10thebeststandards of workw.tnship.ThisJ isusuallystrappedwithcircumrerential :l:ldvenicalsteelband,,:h:l\'i ng:,minimullldi sionof75mm )(6mmand50 5 mmrespectivelybolhsplIccdatIIIICCI\{rcs0 exterioror thebrickwork. Joinl sformtheweaklillkin abrickwork:lndhenccutmoslshouldb..: inI ingjoints.whichshouldbeasthinasr..:asiblc,Forhrid,work ,IhcIII thi cknessshould110tclI..:..:ed4I1lm,All joints shouldb..:wi p..:J.: k:lllI II!"l'sl ti,l ;!l'idc, Jlld tion.At corbels.the j ointh..: lwccnbrickworkandcorbelmu:-[benl:hkhy speciallymouklcdbricksandinertpading.suchas:lIl11l1in i/c.ISimilar arrangementsshouldbeprovidedhetwce nthebriekwllrkandchi mn..:yl 'OlP, (b)MetalLiner Theselincrsmaybefabricatedintheliddor nltl'rnat;vcl y il;o:rsit.:fahricati onsho suitablelengths termedcans.Such1Ili ncr shouldh,l\'c aminimum thkkn.::>s or (.mmp: allowanceforcorrosion, Acan shouldbedcsigncufor that canduring its lingandtransporttothesi te aod sellucntialandtimelydeliveryor cans 11 'thesi te1111 ensured. The favouredmethodor erectionor sucha isfromhothl!llUjl\\';II, 1s.Call weighing5to10Iar.:transportcdonlrollc), sh\thcinsidl'\l l"achimney:-h.:ll. 'l"h\'to isplacedfirst andisti ed10wircropeswhicharegrippcJby j;ld, s atthetOI chimney.The fi rstcallisthenraisedand thcne xlcanplacedWiderit.Thesecansarc mallyfullstrcngth bUII-weldcdtogether nndthi smustbe d01k'by wcl l !r:lilwd\' lIpcrtw( Duringereet i!)n,thejointinaisbri dg..:dl' I"':rami;\ I'\\'/"cOlllpic!i work, gasti ghtncss orwcldcd j uintsC'l11hcchcckclIbyasnwkl:h.'SI.I,in,'r\101"\..isnOI onthecritic:,1pathandhcnceshouldhe l'ardl:1Jypl:ann.:d.Ins utali.\11i ..U"U:illyli;.;c' liner fromaplatrormntahi ghcrlevelasapar:ille1activity, Achimney,whichhasnomoving parts,looksimpregnahk. aresult,n inspectionandma intenanl'\!or achimncv :tnJit slinerdoIHl1'Ill:lll"r,'{'ci\'c!Ill' ,',Ill theydcscf\qLiningmustberegUlarlyinspcclellandlep:'l ir:;.if r..: quirl' d,should11 postponed,Similarly allm:ccssoriesshouldheexaminedregularl y.l' ,g,carsfo r1M' SC andcorrosion,li ghtningrcot('clic1I1SYStCl\lr,'1"inellicicnt j"llinb,ch:, ! I I ., 13 MODELSIMULATION JIhas been invogueto study scalemodelsof structures inwindtun neTstomirror the for cesallnnlllhe response of:l prototype.Over the yearstherehasincrc:l.:oingrdiance onusingmodel-lestresultsfordesignsincefieldtests onprototype haveproven theadequacyof !> uchaprocedure. Thenon-availability of areliablemalhcmaticnl modelto an:ll ylicallypredicttheplumebehaviourunderabnormalenvironmental ort opographical conditions andthesusceptibility of present-day slender chimneys todynamicexcitationhas increasedthedemandon wind-tunnelstudies to be carriedout using scalemodelsto predictprototypebehaviour... Itisnottheinl cnlionto describehereinthevariousmethodsandtechniquesadoptedin modelsimul ation,testing :lnd interpret:ltionof resultsbutrather 10expose thedesignerto major of modelling andtopointoutthe ad ... antagesnnd limitafionsof model studies. 13.1NeedrorSimulation Amat hematicalanalysisisin\':uiably cheaper :lnd faster than using scaletestsinwind IlInnds to :lrrive at theli kely behaviour of aprototype.Hence, a formodeltestingnor m:J.l lya riseswhcn an :ldequate :lndreliable anal ytical approach isnol avai labJe.Thisistrue inspiteufthestrongleaningtowardscomputerisationnndavailabilityof'sophisticated theori esinabundance.Amodelst udycanalsopro ....:useful10confirma.mathema.tical solutionandfordetermining wakebufeuing effectswhich Canbepredictedonlybytestson physical models. , I ! , , I , I ....... _ . r ....- . . . .... -... . ._.-222TALL CHIMNEYS 13.2Simulatinn Asappli ed10t wobroadf(lrphysi.::alsi mu!:ll i\HI.;He::ai determineI he I rnnsporlallddi:.. pcrsalorp\)[JulanlpIli t..:hi llln.:y- :\IIdthe1)lhe tocheckIhcadequacyofIhe chi mn.:yas :tSlnK'[ure,ToensureIhalprtl lo behaviollr ispredi ctedonallI(lIld[0all:lcccplablcdegree of c\' ll sitlerable:11 lionneedsInbe- paid InThemodelst':dc !:!wuld11.::;ullidl'nll.\'/ars,",sudl det ai lsofimpllrlanc.::11 \'a dcqU:II.:l ylIIodell ed,hulOIl1111'l illh'la r!!!:nwlld!: incrc(l.scthe e>; lclIIofwindl unndbl nc ka tteandhIIH.: k:l geo..:\lrr.:,' I1ol1 unccrtain, Inodtlilion,whenscatin!tla w!::m.'appli ed\I)nwdcl ilwillhef()tl1ldIh:\1sal isf onclawoflenleads 10violal ill ganolhl'r,' I hus.itisgencrallynulplls:. ibkto sat isfyall desircdSCllli n!::paralllch::r"ant!hellccan':IMlllahlchastn/>,.:11'l','!'ll'd:11.,\ decisionrcquil'cs soundjUI\!!CIllCll tbat.:kedby experie ncc, (a)ChimneyasItChimney The purpos!!or suchsimuialioll tlltheSi/.l'allddI'WIl ' WII1,\ plumecOlllaillill!!pllllul:tIlISo.:mill!!11fWIll:1t'hillllh::y.'I'll':p:,, :w:eh:rsIha l iU1porl:llllfurs uchsimulati ona rc: I,Windnow('liartwkri .. lie s 2,Thermal rradic ulinIhc .tllllosphcr.: 3,Ch:tC;lclcriSlics of Ihe cJllU('nlandil ;;r'll .:ofF Ilrlher, alllllll!; I he wi lid1heimp"rlanl nnl.' :, .\I "\\' 111,1sl"',d :LI,dt urhll k These a r..:sil1lu\:Ll edin ,k,igllcdwi ndtLllllh:! ,\\Irhth,hdporrri ,! ...\'(11"1\:'\1: ral ors, cl ,',T bt: }"..:I"Ih,'wdl ' [...I1LJ\\11pruhlcllltl,atilisIh'; loJa!L,ll1c,\u:llil Rc,bUIt hisi"tlo!aserilluslimi[ aliollinSIUl'CRc'\ill\'wC: lkl ynow chara";!..: ri:.tics, Inspeciallydes igned11: .. 1raci!itics,theprl'tiickd1':l1Ipcra lul,'I'mlik ,'an h: Si IllUI:lIc(\ anelworkIll' heatingt !Ius ad1ie\' jllg el[u: di l y (lr RilL! 11I \l'.' I.IIIHII.'\'lT, extremel yditlieull10lII:ll lIlalllIhistWI)liI:.::m'erti ll'l'lllir..:kl1;, lhIl l'I hI.'1,' .. 1 ""'\'Ii,)11:Ill si mulat ioni" \ ' [1 ': 11limil l.'tlhi rqll..Ih.'lllrallyI CIIII',I:IIII 1"I' Tosi mula le elllllenl\) ..:h;1\';I'll l'tilefolluwingpi 'IH.llnhcrs ;HI.'Impll l'I:l nt: l.2.(p,,-:t4.(I,,'I 'K'/)IJI' EllluC1l1vcloeiIY(l!1l' a nwi n .. 1 DilJ"crclll'ein de ll !: il ),h':lweenair ,lilt! cll1l1,:nl Ikm F 1 , III I.:11 U I11 hI.: rllr liSd 1s;lIl:! rIll' chi III1U,:Yc,: ul redep'.:udl u;:. 011will'! !I\'r IIl:ul rataxil f.all swithiut hesectionorOlllsi..1 ...;1rc!, y, y .. y y ' .. y YI,Y4 u. " ;,., vertii,;31ddlccti on (If theiuna ;llIdo utcrportio n" 'I)f a"Iall:rcspcl.: tivd) (posi tivewhen dencclionisupwards) ,i''-vertical(lxi' llload,N... ....oflJyperbol.o.idcircle UplO under eonsiderati o " '! ..,'\. , .. ..oftireeehulg,m.'':',1" " , , '.'verticalaxialloadcapacity ofa sect ionunderlimitstat eofcollapse.N peak. .Ill . -. ',.,. rmsval uc(If dynamic dcllet.:lioll.III sl aticdelkction.m supportaccelerati ondue 10 earthquake,III/S2 ,:!.lateraldi splacementatclcv:uioll=,III ,' h"; :'.'lateraldisplaceme ntatel cvationtilltheithllIode.III ___ tensil l';oreeinsteel inclastica nalysi s,N as1'1butmomclltorfo rcl')'during clastica nal y:. is.N III elevationabovegroun ,isgivenby dw,;,.a2 ' 11.2..M. drO.85D(J- 2),a% (Il. I) 24()APPENDICES .......... - -. &.. Thtradialmomentat ,\\ ill b: P.! h i.U. I . \/, ". I. \/, "..('.) f .I. anditfollows1";11 , " (';' "") M ,' ,.-/- I- ::zo' 1\'\ (a>Membrane Fortes ConicalSbcll APPENDIXC SHELLOFREVOLUTION Evaluationof membrane forces for three load casesisshownhere in detail (refcr Tabl\: 6. 19), For 'other casescheml!titodissimilar andhencenot detailedhere. Self-weightgpe runitareahasaninwardcomponentPr - g'cosp andacomponentalong theshellP. -g'sin p.Usi ngEq . (6.6), N,- -g'$'cosp'cot p and N,-s2' smp Theconstantof integration C isobtained fromtheedgecondition.yiz . . N, -O at $. SIand weget N,,,,g'(' _') 2's' sin,SIof P. -0 andsubstituting valuesof N, and N_in'1.(6.6), wefindN" - 0, Moment 01WaistCircle Inthis casethere arenobodyforcesLe.p, ... p,- p, os0 andEq. (6.6)reducesto dN,I1uN" . - -+- -N,+---- - -0 (Isss'cos pdll deN,,) +1:...N,,-O(C.I) d,, I " I i 242APPENDICES Theseequations arcof thefurm, whichhasthesolution U - [C - It/, cxp IfPl/p) dp J exp ( - JP,14 whereC isu comlalll.CtllIlp.uin!:wilhIIIC scnllldIll"I q.(Cl) and C - X"P(dp) = 1ft?) '"0;ex!'(- JPfly,) - expt - IIIs} ODd SubstitutingIhisvalue. inIhe;li,:.1equ:llillllallt..!plt1l'rnliu)l. ;1.\bd,',,. X2X,0 N.""-+ --- " eos $.f1. cosJ> where constantsXIandXl arc10bcdctl'r.ninedfromedgecunditiuns. ExternalmomentMisconsideredtrunsfcrn:dtotheshellthroughvati..:al Vcos6'(Fig.C.la) ,. M - f V,l CUS20dOI.l' ,v .. .11/" ,/.: '.U Tbisverticalloadhasinp: cos "'.I Y,in {iJ/21 i 11" sin(f1/ 2) ..=cosy cos'>: ( b ) .:..;. --------- ---t---: /' +, Q "Q C 0 - -, , Z, , , ", ' d9 i , "I 'I', L{ .--Pi, / I :::.... - (c) (d) Fi g.C.2(a)Moment at waist circle.(b)HVparboloid ,plan (c)Hyperboloid.Cd)Loadsonelement ofs he" FromFit;.C.2d, resolvingforcesverticallyandhorizontally. N. - P. acos Bcos ,./, . sin f - M cos 0Jn-.,lsin, APPENDIXC245 ........ .--)-/' N. - - N. nI'a- - M ' Q4'si n p cos 8J1I',4.1r N.P '9 sin ,. . sin(12) ",- - ' u'sln'.-,'SID Cl andfromwhich M ,.J--;;i Shear- b21- - ,'sin 8 .".-rr ShenrP QtWaistCircle Letthesbearforceataoylocationbe p ' sin 8.Thenp. PI1I'a. lnClIe, --, -dPI "P-a' si n (9+,.)d812cos ;dPa- - P'a-sin (8-,.) dOl2 ;os' whichyields. ,(0/2)P bJ.' N.- __ --::'':::':=,::-;:.1--'co58 rcos11""0'$10,,a N. ."9cos,. sin (PI2) .,y-Stn.. rcos er; fromwhich D' OZ Shear .- 8 fr 0" , . III lil !h li.j :.1 .:! 11 I 'i I: .. i 11 .1 , :1 ,i I .;, 'I 1 I :... 246APPENDICES (b)Dl5placcmellts andRotations Valuesofdisplacemcntsan.,drotalioll5areobtainedbysubstitulingyuluCIiof forces obtainedfrommembraneanalysisinto Eqs.(6.9a) and (6.9b)."thl!uppersigninexpressio focand&0inTnbles 6: 19and6.20refer tothelocationwhere0 - 0withthedirection action of forcesandmitmcnts.liSshownintheto.blcs. Equationsused(0CVClluUlCdisplacementsandrotations- ellS 'P andthetot al Icnsi l'Hwilllw . f) 1 ="(CO" 'P- l ' OS },r/y ('I ISP- C(I Stp rtfe(, '" -_.-.,. .2mpf.) c()s fJ - cos 'P ( LeverarmorthisrorceahotlttheNi\.isr(COS" - cos y)andhenceInI'tHenl,)fte forceaboutNi\.willhI.! ., I> )"" -..- ----. .. - (cosp - cos y)- ,h Cll .';#- CI) S P ,.III!' ( i) ..fjcos !? E}(prcssioasEandGarclherespcclivcintegrals0.3650.323 3er0.5'1 0.45&0.4210.3810.339 1\1!(, .-;I, "I .;',1 \! .I I,. ",' 11 I ., I. ,I I \ ' 1 I tll '1 1 I r .' ..-APPENDIXE ,.. _I,_ SHEARANDTORSIO.N This i. basedon referenc..:54inIheHibJiography andIl\: rctheIIlcllmttislailored10:lllal)'lic aacc:lionwithtwo tll'pu:.ih: opcuinl!.s, (.)Erred orFrom strength of materials (Fig.E.I) , and M,, - -Ify dA:M,. ... f1x dA , iw. I , 1 I " '1 FigE.' f- _IV + ..'!. ' ! JCI+ M:.:JJtx_ 'J' AI,, ' /,-I"JI/"' 1, - 1;,, withrcference10Fig.7.5. T Iwd I .,(,ljJ ) I.c.lus" - - ,- (/=.1.1 (E. !) 1; - _ll J, dy dz (1' .21 wlll're/0$ist heShl':Hstr.:ssdUI!h'shea r forcesQ..and Q,. Suhsll llllingfor dfldzancr dilrercnliatillghi. r.1andIIlltingIhal Q,. ., _ (IM,andQ,._ (I:dz los - J...[Q" ' !JI - Q,/", .S,.+Q,' !Y: Q"/JlY.S.] I''' ' 1, - / ".I. ' l,-I.ov (E.) whereS" and areamOll1 c nlSabouttlu!x alld .v axes respC'Clivcly(Le, /y,(JAandIx ' dA. respectively), ! I .. __. ,_" ____ ...___._.'J APPENDIXE251 Considerth3t"asectioniauraels shearforcesQI, andQlqactingthroughitscentroidal axespandqrespectively(Fig.7.4),Pror.:eedingasbefore, moment.'attractedby thissection \\ illhe Mlp - f f ydA A, and Differentiatingwilllrespect(0Z,wehave Q,- --- - - -xdA-dMlqJdJ 'Pdzdz' A, Ah,- J /,x'dA A, Q,.I.y ) + /t,,(Q,.I,. - QI:I,' acceptable.. (iv)CICINDhasoutlincdalimil-:.lalt apl,roachf,.rt."apa\,lyI,r; chimneyshdl clemcntunderIhc :lclionof:1)I,i alIO;l d.Iransv\'rsc1IH1IllCn andmoment sduI'10tempcralurc and corhellHads. (e)DynamicAnalysis (j)For:1dynamica .. al )sis(If chimll l'Y:'" 11slli lil" Ih"lsoi l inl cral:li lll1sho uldhecIlll sil left."tl. (ii)InSl."c. 9.2 il isstal Cl tIha1 achimncy 1111111..\,1)hi l'\' linti lll "lar)!,'"'I' III:llio:1"I K.isIhan:W :11111f'>fI';tr:dldsid,.,;lIId11i nowfdt'hatthisro.:lJuirnHclI1isIloI:rh:tpsloll>(I{,I NDr .... 111: , investigationfor "ortoslt l."ddin)!isIll'!if fll r:111kIds.c:I I'',11LN; m whereC;istheweip.hltor ,himn.:y:th.. ,l,':l k"d :111"VIho.:'"" hi hI,'.,1'ahll l thesamelevel. (iii)ThePIS!factordl:tIlI!C'wllhlu:i!!h!.Tn :llhmforthi" rl1".,c1ailequi\'alclllp.nstloa can beused,As Itrt slIlI. forevalua l ing nltln)!..winJrespom,.!lwportilHl " J n, ' " .. , d= " inthernr 110111Fq.(9.111 ... .:'"hIli,I cl'l:1c,",,, /1" f)" ,+ ?"I' ,I" (iv)Ttisrchthataenrrclali,\nf:I.:lnrhigh,'"thann.(.(rckl1':11:,').I(danti\.'1.lIU" may 10heifl> htlrtJUf:tlillllJlC:tJ"(f)Linin!; Thereis e"idenee10I halilllcri,.d,.ing hrieb l wit ha shall, II\'fIlIl'r l,lck),m;lnufaelUrt """1"4 --'-1 . - .>,. I j G281 to close tolerance., clI.wbitmorestrengthwbenthermally loadedas comparedtooon..lnter. locking bricks.' ... (a)Cooshactioa (i)Technicalspecificationsshouldrequire thecontractor tocarryout acomprehensive designfor allelements of theproposedtemporarystaging. (ii)Thereisa need to developa comprehensive qualitya"ul.ncedocumentfor i chimney construction. It should coverrequirements in6f.1structuraldetailing,concrete strength,Jabourskills,degreeofsupervision, measuresforsafetyof men aDd equip-ments,planning tJ.ndscheduling, inspection abd maintenance, etc.. (h)Aerodyaamk Eff.... (0Model studiesshouldbeencouraged so that guidelines can bedevcloped forUseSSiDg bufetting cffects on chimneys duetotall structures (e,g.,boiler planu, coolingtowers, etc.) in the vicinity,. (H)Aviewisgainingacceptancethatinstrumentationofchimneysshouldbe made mandatory. Then.data can begeoerated about along-windaodacross-wind oscillations ofchimneyswhichbasto beduly correlated with corresponding windspeed and its distribution. This willhelp intuning the existiDI deli," methods. ,' , .!- :-'.--'" , ...'11 " , ..,, ,I l , .... " t . " " . / '-' "--- '- I I " I 'I ! ! \ -, ". ,11 j\1\lD'If,1.',!'1:. ..1. 2. ,. 4 s. 6. 7. "" AOA\I.\YAL,SCANI>1\Kal/I'T.. , "Chimney h"ilthlfur I"C;C .[SCE.V 84, (ST4),p3,per1712,JulyJ958. ,t'6.PeLLOws.A,"Concrct echi m'lcysinAustmlia", COlIstr...V 43,n 1970.JJ46. 57,FINALREPORTofTaskC.amnit leconWindFor,es-"Windfor..:cs0'1 T,ans .ASCE. -' AIl V 126,p3,rI2.1961,pa pl: r)269. 58.FLSIl I!ll. , O11."Counclest:!,'OnLro!forvo:rticalsl ipfofm;"s",J.ACJ,V 69,Sep!.1')]:1.,p5S6, W. Sfrf!$S('f"" SlId.'s.Sprin::erl1erlin,J960. 60.- FORT 0nANI)MIt.;elll,I n " ," ill ,l.!;igl!:lolld;nst,l lI:1l iUIlvf c; ,i mneyCOS VI. 61 ,FtJNO,YC ,liftlImldra;:aCling OllItcylinder illaflow alsUflCrcrilk'llRc".J .,'IA,,I>. &1., V21,Nov.60, fl 8Ul. 62.Ou.sCOLlJNE,JK,"Thumal, ,hcmiclIlandnow aspcds-The combustiona'HIpf,1 Sttutl. V 49. J une1911.p255. 13.I RWIN,A W."J)yu;unicro::sl)OIl -;,'.. rlIIultilluc chimncys", COS.VI. 74.IS:1893.15;"Crih,lr i:1[or..::,r(" I" lker": ';1.I) I.! J,Wi",((hCjf/llliullf SlnoW",".NI'L.HMSO.1.'''1Insol:'IIiOllclrcclCl7 InsuMi on195,203 Ladder209 Laseraligning216 Lift coefficient182 force39 sptrum39 Lightning prolCGt1Qn2UH Limit:.. tall: cr.llapscstale -cmcl..--width 141 176 denl'cli ul1176 r,\ni.' l:',. ;: .,.,'.:t H'T\I l1mli'("0 slr6:.. am!:.. 1I':,;nVarial;,\1I 176 u\lim:l tc " 14:'1 Lining c(lalil1!!199 CllncrCIC19') 220 corr,l'i'll l1')(, desi!!1l199 funcl ions' '16 hbll 'ry2 1ll":"" II1Y11)7. I1wlalIl)x p\:l ' l i,"I'll) proper! ! ,)(, rou!!llIl" "12 dlceh4:>: dh-dc.:; Ihertn:1 1 C(II!(I 'll'll' il::l}'IlC'191 windlu(ttbon.\ 4 \-;I1I";(li'l1lI. ock-in33 Mccha ni ca llld1llitt:ItICC184 Mix.d(':..i l: n216 Moda l allllly, i..; 4(, higherlIlodC',4h mOllll'nt47 multiplierIH.l p:lrlkil,atillllra.: ,,,r4; 47 Modecodlkiclll410 Model IIOUI :lIIOII 142 Modelstudies(COl/ut,) nccd221 simubti on22 1 ofeI,lstieity180 Mortar aggrcg