I \ VI: ,l; H “g , y I! w H' ‘; .Hi \ I 7 l M I II *I 122 293 THS DETERMINATION OF YOUNG'S MODULUS BY THE SONIC METHOD Theain fer the Degree of B. S. MIGHICAN STATE COLLEGE Norman Precoda I941 ‘ ... VW.dAF.¢-¢dw3.‘ w t.’mul III to" . s n . . v I I . . . t - V I o _ ‘ - - . .\s.$\,)$. _ n . u 0 ‘ . . . I o . . . . . ~ . . . v u l a l u . v (.2 . 4 . \ Q I . \ 74 ' p . l . A . . . . l d ' n§ . r . H . -. .. . . ‘p I r . . § v ‘ . . . . , L . . . . fl _ l I § . . I I I I a ~ “ / I \ . \ a r I... f . _ (- 1| . i O I ' ’ . 1. | V _. ‘ 5A In... aflhlj H 4. d, ..V . . I. ‘ , a voJCN..l$\ . .v : Ffiwmfi. . ..\‘ am 1.4 d 3 I u f. A \ I. ,.t .J. . ‘ .w‘ l5, . <- h‘ ‘1 ‘ I- > ‘I . . vr I . A» . . .. \. 9 . v . aI' I n‘ l u l ( \ c .0! ‘2 . .v\ a 4‘ ox AM: o I v 'I D K .o I. . .‘Dlaqv ‘- Detxxnhjnatjxuw of anumj'e ;IVH1]HS By tme Sonic hethOd A Thesis bubmitted to The reculty of $ “1.011 .Lkgrnil- Lfi‘L'A'L'E U OLLEUE of AGRIUULTURB AVD AFFLIED SCIENCE norflen Precofia dendidate for the Degree of DUChOlOT of Science dune 1941 (THESIC 11511473 01“ C 0:: Shift” Q PLLi‘ -rJJ I INTRODUCTIOI‘I . . . . . . . . . . . . . . . l fiecflground — general rroble» of vibration - Specific groblet as covered in tnis paper 11 DISCUSSION OF USE ULw,uu . . . . . . . . . 5 Results - possibilities .LII J’Ll)PJI;.Rr‘.TUfj .ILI‘TD 13p ‘.C)()IJi IDIJ H i118 o o o o o o o o o 8 A-Derivation of working forwula . . . . . lO B-Correotions for rotetory and lateral inertia . . . . . . . . . . . . . . . 18 C—Flernrel vibration RP7WW retue . . . . . . 9 D-Lonqitudihal Vibration apparatus . . . . £4 E-Dynemic teeqs by weens of Infinoed Vibrations . . . . . . . . . . . . . . . ?9 IN] C 1'" ‘3 IJY :3 I 0:” o o o o o o o o o o o o o o o o I‘) :1) bIj-3LI (1'RI‘1PIT—Y- o} o o o o o o o o o o o o o o o o :16 136176 DJB‘I‘QiRTV‘IFU’UF‘IW‘T Oi.“ YULJ‘I'VPS TWDULUS 7”! ‘t."‘Fi SUTIJ Ja-uuh'hUU The method of tefiting veteriele by vibrating that 19' 451.1th ”7317.. PT"'“h-fl§‘iy "‘11,", of tjnr‘. '3th (3,0,1; (an e313 olesa'is than: of iflie “UftfiljfZ ourwvmdoy, (joingztjgrp StTUC“ on TWO tEle 0? FR? tn prove their fianuippgg by the rietflb: tone given off. (Porhers ~ore en in a tiwee beet rather then in these oeye or the r H 1, end the T-men) Flower? of tine 91399 tented their weree to Cetect YlFWP by the ohrreetorietic sonnoe DT“CUJCV by the good find the bro erocwwene. ’rhe vib- Y] .1. etiozo of tre reeo, the firum, the rovirq colurn of .5. FIT in a Line —— thus Whether ren“fini7ed or not, “he 1—]. LJ. ' ‘ ' "' h I" . 1‘ ~ fit a” f‘ ‘7 . 1"? ‘ o . Oh?1%MTBPT1CWJ'C v rwurtion ri‘cm'toby the; CL¢;?U.EVV e pFrt in mor'e lives Farce ti~e ir~wrn"riei. Very likaiy ”to natural frornercy of vibration of e FlHQhRH strinfi “an the first to be studied. It wee reietiveiy easy to Pee the lonjitneinfl “eves *et up in a flexible core. From this, the next ster Wse iflio °t7Njg of tbr~‘ribr€tfi<fii of p :Vwi hr rfiéfi(i oofiy, Of Tflws eevvrel ryfifivv‘e if helfl'r¢::7 ririd_3vw§;, ire three meet com on ere: (F) the fifeo—frefi «er or wheqwi ore 9rwi iq fiWHiit-in eflz the fi'flfiN‘Tt end Tfiwé otb“1‘ jg; Tiwee. (13) Tfiie 1353‘ lWIiJJt-iii at; twittw err“?. ((3) T110 ”r b3? Tree at Y“th PPflF. The free-frvfi yer it; one "wt;rily ed :ILy eurnwthoo et.11=e ror:]- f‘; is that irxiflue oese of a String, vibrations ere mainteineo by tension er errelly errliefl' Whereas in the r06, they ere mainte red av tbe electioity of tne rod 5,8“lf. Due to the varieti"n in the forces wrought into eotion, there is 9 wide vorietion in the kind and the Successive rates of vibration. uenerelly ‘the sounder, veneer body Will beve the hifiher refie of fundamental frequency of vibretion. Sir Uberdxw3‘fiheotetmuwe,xflith the gi(1.gy hjs neleidornone, studied the eotion or a vibrating tired- lree ber. A brignt Silvereo beeo attached to the free erml (ii‘ a. Imyd. tits i1 Lu 'j11813e(1 VIitli E: tweeil (3f -LjfiThll. When the roo vioretem, the beeo ewowed es en inten— selgr brfi.ulierfl; symrt eiri‘xassesesjl f oee11. UHUlS 3i; VHS possible to record toe fireet variety ‘md beauty of fflle (weeizrnr: pI*“dvu3efl hy"thré *rvvirig lfieetl. lie iffliNld tf:at; ttie 'rrmi \rjlrreiief; Sigwtulliget7Prn33J;y '3n tvn: {wfi‘ffihll— dieulor airoonions and the curves ;roouced uy the "I quhtoc bead one to the COJPlfithFNS o7 the two rect— SCHFCHGTS 10? Knowledfie, Uflxa‘vibrari“n of E boby the iJPCTtFan of the erteots of those vibrations on t; CriI‘ i;alie<7izatge SJIP17011P(llllgfi? 7,94352762 G179 fllfl y... "\ oviofnt Thlfi 19 in generfil, tpe esseoce of tbe prob— ‘or tflw t rope-Ila: HTjGT (Memoritt— leg or vimwnrtion end }.L ion (H ;;ethoo (*-7) has ween ‘ Hear y e - . A L {it Fly Bike "'71 8. Area. BQIIQLZLL toy or of the general C? k \ A ejiric ~l testinm am 2“. 1’0 C 53(- 3.1 It will I. O“ Lilli F7 F, 7.9 «‘ TTC F 1 O 1.9Lmlr .L lirov11eII 3ND OwLFlEy 2: 11" t-‘1W'MJ- l" L 191'; Joe:lne :I Alf? -~ w- . ~: J_I ' '11 .0, :41 LL‘I kIEC' .L‘Illin FltTi‘fi'J'Vl-i IMDESJ. ycirrts ”‘1 "To rm n n r 1.3.0519 1 (?\.,]>7»7]‘7\7_J:’. JléwIlz‘e .roiiLiorI r—v .. 3- Il ;U Bfilfifi LS of ’Jlli C1. 170 F .; 7- - F11 (_I_ (V. 1:1: I L]. 0] gr!" LLLE‘II ." _.. 1, ' . 0L IAllP T T‘IJ‘J_S ::o be Ft ”n O in Cortirxrule internel L1 .L p l i. S a i V1 Lhi‘c'l »"ow it <91 l '1. TFWF’I ‘./O‘ L'“ he ("0 1 T: 1 (‘TI be melonlet MP ireo E7 y c (' , 1" V ,. (. ’]:L l 130 ' 9.. ,<.|. 5‘ T‘Im m‘ Man O k 0L I 'n~ -. . 7 “ I I”? F‘HIFTIIC ‘24’ (I Cot*rm l\. I") } /..‘ - r1 4- - n. L 777‘: 3. too I 0 j 2777‘"! 7",” VPI‘l-iéf‘ . .7 . , . ) \ I . D ,0 I'll VT 5 TT‘ ’3 ': ‘lr‘bw(\1) ‘ (-11] (.1 {I I“ t; n no 'I‘" -J goreible to reach a corresyonoing resonant freouonoy irI tlma sgxeoixvorl. LLf flirttu2r, :3 dwrvitna is: attm7obfiwl to Cheoiwer (oreferJIlv rt the ends Piroe the U'Tllt- of emrlifying vibfetione produced -— then it "ill be roseible to select the fnrflemehtel natural freemangy of the ereoiwon, since wt reconenoe the ewtlitufie of vibration Will be e merimnw. AMPUTUDE VAR/ABLE FREQ - METER L UE/vcy DRIVER A it? lafiflAl SFEIMNflSA/ 7A” 774;”- ' l ‘0. £24 Lfi #0234 L—u ~ 1. DISUU‘S IO? 0? UEWFVLUEBS Experi.ents Co.tletefi have shOWed the feasibil- jty of oel_oul'tin? E by Vibretions Witho t toe slow 3 I) suress—strEin weesurenents. Values of b quite 010991? with those flbtfiired ry static methofis ENJ.VWBT€ shrwui to [we Felifflllé. Ewmue of tfius_weterjl. I F... C') which rsve been tested successfully by use sonic Ilelliod.z3re txile, sletmz, tUfiiCK5 .leaul, etvuiiteeiiall. borixi, pert rfir17xer, :roo::.:snrm.lt, aisnhzfilt twistixz, slurrtz bars, Steel, niosle, and rm lrle alloys. (*—ll) Internrvtstion of observed elestio ste veloc- ities in rook of the eerth's crust is tte nesis ior 'r—10 rterrjni structure at incocecsible derths. duoh use renuires Knowledge of elestio noduli Which ere onereot- eristic of tyniorl roe? when subjected to the ginute alternating stresses produced by earthquakes or explo- on Weves. No.: 3t imrortent or the elestic consM nts x)? H v to knoW is Young's yodulus of Elestioitv. Studies \ -o U have shown tnet the flirti,7 1V determined 3 varies '_th tue stress at Whiou it is measured. Q3 W1 .J -J .2: 'D O :- «4 J Y r—l c A “ d -< ”J. (isnslftlly'ifllis is: ettzfilrrtod in: tirry o {MZKS EJNl oevilxies 'on tend to inoressi yielding until tney ere Closed. This uncert tein ty, inherent in all static methots, raises the cuestion of nOW accurately seismic values of s are Obteined, Iona e tre Tress“t trend towers oynfiuio *rfi wetboos for fietewarnrion of m for TOCVS. nor those uFtOTiFlS with a tendency to SHOW e permereht are rltstic flow or the—yield, (com only called creep) the high steeo of the Gynshlc method will prove to :jve wetter VFlHQS for E. This SPOAS to have been verified by the fact that tests by Sonic liet3ru1s ITNflll€UTLy ikmgnd i3 t(>'he e } i§3?3? vs 119 t11xh founfi by the usual static rethod for the se;e ester— ILJI Y‘ 1" Y isl. Jensen and iichert (*—9) so.e compression studies if concrete, round that leesuretle creee occurred even at loses for e serwod of only 9 low M \ seconds. Hence in slower tests it snould we recor- I nixed that error esters due to creep. hometices it taco es useful to know E of s :neterisl uhfler load and its veristion Iron the m of the UNLOFFPG speciuep. yOWHTF THiQ 9rd, Lenngfd Obert \*-10) investigetefi the E of builiing wBtDTiTlS under tressure. (”o Worh has yet been found to have been done on steelm .1.) ns under eny loed but comrression) First the E was lound my the Sonic method using the unloemed free-Free her. Then usjns the SImB SD901- men, it was subjected to pressure (see figure) end its m found eLein. SFEIVA¢EAI [\x\\\;\JL\\\\\\J |/’/’/’/’///’//// -7- Thfia'FisuTt*,n1st anvcefliti: is r? sfetxfii of lute jjffitle f I ~ - ~ _ 0 _ _V‘ -. .0 V -‘ t -_ _ O {aliversel ifVWLUEQ wachyne xuvwi'to rrofluce (my oressjon -« . ' ' ”'uvn 7'\ c" ‘a . r‘I ‘ \ I -. .C' ‘N n" ' . ' r- ' n ' 'u . 1u:1fol.L weurijt3 on TT7u (331: o- (IOQFM Viblkrtol Chevice ermi Difficuf'sxve 117th lxica AME 5%; tin? cevdmer (H‘ beset, but are oriented such that the pickur is perpendicular s of been. cf 0 ,—J-. :3 ~4 1 H ’3’ (D O "b d H 0 (VJ } —J Fl; (7* L.) I Q I3 , 3 ’3; 5' O ”x J "‘ 1 L I l J 0 With this setun it was possible to deterhine the E of s reforiel under Wood, i.e., controssion. Hhe work cone on stone, uith the excertfior of li~estone, showed a to w }_1 Q increese reticly in thm refion o pressures end to ;- —- - — ~ ~ I . ' 7V7 ~.e.» , .. - - - . ~ v ["1 . . .I 1‘ V ' siumnjec}: aocwe consul HtlfjuffflgtflilCV'llgr. lilis Th e clxlto siniler to the chense in concrete beams ercont thet the chence Yrs much lerfier. t Wes else shown thet the no- ioed n of stone oid not choc? With the modulms fieter— mineu under lose. gut lor concrete the no-loefi s E: th=v££ ohtefiiiec Inuier 1 xui —- the Variation not exceeding 10? for normel credes of concrete Stressed up to i of the ulti ate stress. I’D 1&)PJLE{J£L‘LJL$ 49:11:.) f-)()U-1.:1_)\_AL_.1L"JL , . "- .V ’31' . .'r ._ -, .l 41;.)- L.- H O Ho '7 5 :1 CD ‘1 f) "D \3 D —+ O 3 DireCLly fo l!(h1 1 (J. ’l'fuflflj Y 5.x: da‘x"1ty (H. e rgéec] e, ’“hnnc relvtdxflvb als One LJHE {Leis loI'Cnflculct‘g urnitu“ «i el}. O :0 fl.’ YT + 1‘1L'Cr (1 6X1 when To *U '1‘! note: Vibra m“. "1119 unles of a 17'" 9 1‘9 -14- we 0 —. 1 ~- né: r6 or cylinoer of ‘AQiUS - r, n tion. constant he 0 nnot he rcgcrdod PS 8 valocity S‘we (Elvide iJL'hy a.ruiflntiinf of tlwé dirfwn?inns length, viz. A. AS Rfileigh points out, the ac ission that harmonic waves can be trsns- mittefi at all is sufficient to prove that tne velocity Aust vary invwrsoly PS the wevelcngth. Conse From quently we LUSt have C(tTFUSVQFSO) = E£(long.) - " * ¢ A. y“: *dlifl I 9- ”’7' 9‘4" r 0 . WA ‘5) __),d".’ + Ali-~03 - O or {111ch + EI_ m, - O C: X 'p d X dX‘ dX' .J Introduciufi ancalerfitihn 0f HT vity into 99” tion. Let I 6% :21: d)“:- 1 my 8 Jr] 0 ‘-‘ ‘-’ t' denlsi frequ lengt bl - vibre ,0 . r3 .. _‘ 1 = Ah“ Thom pmdfiz + LIM4V = Q 01 g gdxh die 6", f. 0 ~ u + aad4v = Q where a = ET” d X 7 CA «- w i._ ‘3 lat inung’s Romulus, E - p flfiflLL ty of tha body ency of vitratior h of tin? Sp cim£q1 roots of etuation (Dll) and dmpcnds bn node of ‘- tion 0? tn? Steel‘et- D . “"3 .45 Let Ncrfel.j«mie of vibretion lxésnufin'ttet deflection at any point varies harmonicslly with ti e. Let X = f(x), vtoro velue of ebecieee x, determines Shape of the normal mode of vibration being studied. From (0?) flag f egd4v - U , a of 3-; “,1 A! n ( Lot deflection y -[; ACoert + ESinri] II H d ”X '1 :3 L.) o ‘f ‘3 fl _ J U) substituting value of y in (l) which second [3‘ 9 O 0 ‘ 0 then twwxxues fi“x_ - I“X - C) Lettijngir = YV~ this dx? 8“ e be written d4A - b4X a 0 end is e differentiel O 0:! H | .1 ’4. m equation whose solution *-1, X - uiobx + Cgebx + 038in bx + U4COS bx V. or A ”oen bx + U Sinh bx + Cgsin bx + c Cos bx 2 4 ll 0 }_.| C in which 0 On are arbitrary const"nts fietornined in each case by conditions et end of the bar. - Geflection enc :1; Caoe l Simply supported en t. .0 benalne moment - c X - O, div - O A dxr ere ll Built-in end — deflection and Slope of 3.; \‘ oefleCIion curve - U. K = O. ' ‘3 - 0 i :1 54 Cree III Enfl free — Lending moment and shear = O (1?,‘7 _ O 6317' _ O 63%: GXu Rewritinfl (5L consten,s are not identical. U1 [E309 bx + COSh bX] + UnEQg bx _ COS}! bx] _ co[;in bx + SiLh bx] + cfi[;«u bx — Sinh bx] (fl “akin: origin of coordinttee et one end, then by “X uHSw ill, for a ber With both enfls free, there wijl be four confiitione: (i) dPK = 0 (ii) d3: - 0 x~= 0 dx4 X . L ox‘ (ill) 63A - 0 (iv) 65A - U X‘I U dLX X -_- L dth O 5, When x - 0, (conditions 1, iii), then (Cos bx - erb bx) ll (Sin bx - binh bx) - 0 Hence C? = U = 0 .LP‘ 7. Then X - 01(Coe bx + Uosb bx) + U3(Sin bx + Sinh bx) 8, “he“ X a L From ii Cl(Coeh bl — Cos bl) + 05(Sinb bl - oin bl): O 9. From iv 01(Sin bl + Sinb bl) + C,(Cesh bl - Cos bl) = U l0. bolving 8, 9, when Cl, 05, ere not zero 0 ‘3 Then (Cosh bl — er bl)‘ — (Sinb” bl — sing bl) = U c0 bittlifyins (0032 bl - Lin? bl) - (Coshfi bl — oinnfl bl - 8008 bl Cosh bl = U or 1 + l - BUGS bl Gosh bl = 0 ll. Tten Uos bl Gosh bl = 1 whose consecutive roots are: *-l 4--..3r-r '18 J. 571,18 0 C Tl . t l . OXIDE-3" . (\x;.-,"?T§_ . . 31‘; .V (:1 0 ~- - o o ' “en t tone 0 130110 . bl; . 1.321 ° bgl . bi]. . bgl . by; ° j ._T O ' o o O I 4.750 I 7.?ow . 10.99e . 14.137 . 14.279 : Q 0 . 0 O . . -I nv a (V) . n (.N Univ; (0 (CV) 1[hence e‘ = ml? r“ = r-nn - cA —.-~c-‘ — ”“- pn e Elg Sjncg narrw-wny g = r one m = bl 3:7,: my enhetitution 1“." = 7?. ;Furmlav£flrtcl A / 7 v let. overtone flunfiafiental — nodes are 0.??45 from the once- emnlitude at end.= 1,34: tines thgt at the center. m - 4.430 let. overtone - nodes fire 0.13? from ends and in center. 4 = 10.995 *-5 -l9- ‘0 *-:‘J’ U liR‘CJ'J'l‘IONS FOR LJ‘;'.'ESF{;~.L LIT) HOT-.11.”? Iii-1119.11}; A In the derivation of the for nla for loung‘s .1. InOdlLLUS, the (affrmrts CH? rotmcry iruxrtie.vwx“o FWtittod , O . .0 _ ‘ v N. . V%:e lIUTTTIV‘CIElxle =naettz‘the d. for sifiplicity end since i cross-section is reletively ewflll in conferison with the lenzth. Pwt Where croes—Pectien of teen in a cownvratively lance f:€ction of length, rotary inertia "ecomee e rreci :1y 1?? e. Einilenly, the effect of nexlectinr effect of lateral ine-tie intnofinces 10 etnrecielle error ThOT~ the crowe—eection in small but for bane of ler e cross-eection-to-lengtn retio, the error introduced in neflecting this term heconoe sufficiently larte 38 to deserve ottention. LJ. Following is an ex ct eolut_on, ty W. P. henon, (See regerenCc 5—5 for material on this subject 5150) for frccnency of vibration Where lateral and rotary inertia eye taken into account. This solution given a for ule which in itself in very conflicrted but the curve of the eouetion (Kim. III) Sifltlffiee solution 1(wve 1_. 02?: I ”*diflly'lfiq ‘195V30 . _ V r1" (7 L— , ‘ _ __ ‘.A’_~ 3/1 :1]. — Us[1[l + 5.4.24 ) + m’R‘] } oosh[1[ l + i. > - G (1 ran. C. a - . . ,, 1 t“ , , V y 4 .~ .J '7 ‘ . ‘ C T |'--. (’14 ‘, "J J” \J O Y . v- ‘——« ;J 2,,12 / + ( :31,- 3 + +0”: ‘ ) Rln{-’1[ l + --—-—-;“ ) + 0 :1: ' ' ~ ..'..‘.)/:~: . r‘ .1 EHV‘]*' binh .m[- l +Jn7§ ) _ ,rH,-] i} _ U * 54“ A r -19.. *0 Tects for rotary 4 t‘3 r—J. O }__l -+ Ho 0 '13 rwJ (/ 1’ ‘ VD O J O 3 '3 inertia When the her is vibr:uing in +he fundeccntel Let ml - Velme of w irow curve 'rhen corrected for letejel inertia, who inert'e effect due to expeneien 5nd con- traction of been gay also be corrected for, simemlt- C‘ . - . w . . . . aneouely With inet for rotory inertia. ulNC? the A former is pronort 1o 61 to koi“¢on' efietio, A, Eamon 1 Let H1 =- R(l + A)“ Then let c rreenonding m from curve a mm C .1 now then, corrected for both rotery end 1 +err_] inertia, Ill - p2 (Yn L- B: (J 1.10 5.1 1—3.9].(0 t i 011 1‘(‘-1:"".'..'f\el-l ,.; for Tectfrfiular bar vjtrgt ecentel ween, T‘] v.- . : ' if PI- C“; 111““. {x}: 5: , Sultigly Petio of :entfi to lenith) .ng lit rill? in the func- 4.6 \\\ O ‘- . c" ‘K‘ . Fig. . 1’“ sq. . / llI .v, 17,], l.{’- - n I‘ united Sonic Apparatus used by f. P. Hornihrook in in ireening and thawing studies of concrete for the btetee bureau of Decade e 4’ < r‘ I: -~ otflnttrxs *_4 'runeo audio Condenser \A) e v .. f o J) . r ‘10 twp .LT‘HLL.» OT. ,.I' 0 ‘D USCillograph o «b ungnet type loudsreeker Specimen e .— L=f5 m4)», ”A" Amplifier ‘K\‘ Cryetel pickup (A) N [>40 ce fieceoe condenser With in stere of of free .ool - a verirhle .005 -- I ° r- . p. ,‘4 Lance oi IilCTOLfiiivg- .001 microferede for e 1.11 ricrofr :5. 1'5’ W‘Q Eir condenser he cevecitence VFriFhle total rnnqe + P. O L” .AlPCU cornering vine e totel caneci— The oscillator is . s Iictt )_Jo 1...). to a x meanet-tvre chennel-iron r". 'mounted on r. (:1. . . SlUmlDUM rod which is screwed into three-prongeo that isicloir ("' L). snecimons at the node cemented to voice coil of be ohteinefi. rickup is held to siie of snccinen ‘y ruhi‘er hnnrl. Picknn outnnt is i'ed tnru eainlii'ier to e cethmfleixgrcnmilloirrnh. fireoiunicy (nitnnt to” oscillzitor “r<9 crlitwv ted bv synchroniVinq the 60 nyrClQ Tf‘Os'fPI' SlJITlI/‘W, izod 60, 130, lRO cycle condenser of oscillator is e rixeo Ini tor of“ ‘ves is greah screen correStonning erect Ulti?l0 of the EVE” rgiven by the I11.1‘i'7m9T Of T . < this way Concenser n '3 ( ! n the e per seconc. then edjnsted O O FlPt?“Ped 0T1 L'Y‘r; ,_ k1 cuencv Wh n frequency conplete woven which calibrated over u r (.. of £00 - 2000 cycles per seconfl. This celihretion was CManTa zt verious tines enc was never found to very ore then one-relf of one per cent. ”705D Cilfifllit Of‘CNWIil]O¢ETJfli‘Sith swoop being sync ron— (W7 . t- r Apparatus and procedure used by u. mrire in the determination of Young's modulus of building material 0') he The essence of this method: longitudinel vih‘etion excited in a speci on hy tsrning one end P. s recorded photo;renhicelly With aid of cathode—rev oscillosreph en, its frequency determined by comrfr— ison vdiiiéasninerimnosed_ij we scele. ., ., 0 0 1, Then H = 4 l‘n‘p ) but for r , g rrccisely, m - 41 n frequency determination, test spe imens are generally selected such that the hrscxeted term approscnes unity. hence \l) is sufficiently accurate for a fire, approx- Where 1 - length of sneciwen n - frecuency of longitudinal vibretion o - density 5 _ yeisson's retio n - redjus of gyretion of cross-section stout line of centers of nor ~l SQCtWODP. IQTQbquxwh0 XYQ MQQTRTU U6 QxT Tut)» \A flfloxbxtn‘vxw‘b QKQIQ QMQQQUMQ SO>~ (Qm\> szbek>0>xQV NVSQU .0 \A Q Qth («SKSSVQQT @ Jf‘ / <2 m t. l: w J the .unm E?» w -3 .38 m a x SK .. k Q .395 5 . . J‘MII \ A A out w {E w Aw r w F. i Illllfllll >93 [\Io \. l l; m. g3§ufi0 % BMW QMDQ gauge T 2WX§UWQ6 « a J: A. - Gene 1. “.3 f2! 1) . l. 8. T‘E'il. 1‘~~.I‘I‘E‘=I"..'j‘f‘ff:F‘I!13 2+ .L'J. C) 3 bpeciren, rod or cylinder of uniform cross—sec. is hold at its ’idroint end tanned Ylth e li:ht Electromagnetic detector t'ensror s Ch”hiCTl Vihretion into electrinl volteqe oscille ion, which when amplified, controls vertical deflezcion of fluorescent spot of cetnode-rey oscillogreih. biflfllQ-chvorse tine-base 8 reads out vibration pettern horizontally across screen at nroner tine, [-Jo ne—msrker superimnoses on the rnoto— While a t . f) wrennic record, 8 bFQRK or snort duration every by con ering vihretion pettern Tith the time wrvrfefi, ‘rrerinencsf is (HTtFTSMlDGfi. iled irrzngements' ‘7- I" mXCiter and Detector “Toad (LI) MM??? T -or‘ur 3 qppn -- “2.1/1 on 7‘1": (1i (1‘. “[‘ltr H‘ ‘ .. , ‘1 C. 4. L.‘ , C , k’-.IJ .. J t- ‘4 ..«' \Ji.tx‘_. - L/\A,l _| \J ,._~ I. I U.~ fiTn as to prevent nrrreCJenle translator; movement vhen stru0n xv the lifiht shrine h5w.@r, .ueteCLor'— I” zillijht POlt iron er.eture, {bout l/S?" thick enl ce-ented to end of seecl on is (EDIHET{”fPCE htr c 8 Jill- a lT-H;9}3 ?“r(vn II-Ffiiffl‘ed ner enent ;quH3b H, wou d rfiififi calls or the tyre used in ordinary telerhone TOCPJVPTF. l. l ’ ‘1 O L I .( ,J ,J E._l .J- H\ F-1- ‘er a. Lost suit hle is e resistance—cereCitv unit of ,5006 response in the urper eudihle renqe. n. ln these QEpOWjJPNtS, e direct—coutieo e nlifier of good Characteristics, vein; eveilecle *es uSew, 3. Cetflnmfie-rey Oscillhigreph and idfma-Hase a. Oscillogrerh onereted norgall; et anode volte e or ecu—1°00, according to intensity require onts. D ‘0 IT Potentionetere, P, e0“- 7ijh-tension sunrly nrovlde control or initial position of the fluor- escent sent. h.‘flhere being no neeh of 8 linear tiwe-hvco, a very r r]; Le? Of'C)%CilJJl§T€jfll in EWJflLGS td_fi size? a); Volta e in the usurl way. Conlenser is Cher ed iron oscillograph nign tension supply; 0. when a ne‘e;uf is prepared ior r recorc conee Her U is “hora-oircwited my 2 S”it0n, S ett ch w to fiasu-e1‘ twalrnlsc>, 1), E?fi(' L: e i1l11oiwesm;erit 53L(Vb J.s derlectee to leit Side of screen. 1. £110 in; ten; ‘\ ,4 )._4 I r... .1 P4 .L— ' '. ,, 1 -. , r f“ “(:10 SlJTl;-p E1ryn, l4], Era—LP(J;7GS at Cgrrect instant to Sfireeo end the v.&TfltiOU e. lst £1 vriltzoge oi‘ 8;,grw:rll l -ete_y 500, entree”, (iisclurr e lfiflf F coxnecued in CorLCienSer 1 T‘O'v’~‘ I'WI'L, 7'1 '1‘ , J' ,V . ‘2‘ _:__l.:; _t| “.O_LVI.J I “1 D O I u ‘ .J \ . .. \J F-PI'l "-f S If CIT): E? 'a )9 1...! F'e o thrr~ly«5 culfiwwit, {‘mC *Vitfz it late Eirot Wwel~ciiqy eecreeee e Ton¢nti#lly as cond‘LP'r Cu.r ‘9. Pete of rec 3"? ror 3r:n -'"m 01 ~ r u er~ ceC”, if qua e s ll. tiPC’ lire, "crt ‘3 [any :3 7? V, gi‘oLJe L isu Tin t nr?e(: z,o ixe v42oii ”a 5“ J ’2‘ rr‘ V >». _-‘ __ n , I ~« . ~ ‘- fJJ LlUlDu 1.10 ~ (L . n, L_|_ Flap-LY , ' Pf} '5 ‘Wvllfk l ‘ r ----- " -H-\ -v . r- W M' Q r Eif'l’jfif‘: 5‘13'1FC» Hun LII 5‘; The lJFl‘_‘(,-':1‘kglam‘ ", CWT-”C I ll: C01". v a; _‘ '0 v . , ‘ _ ‘O ‘ ml' f "5 1 ll ’31) (l 1‘ Ll- , ' {(7. fl 1 llV'CCE‘G C(,)I"E""i.31,l‘f r; 1(1’xw Cz‘q ' , '0‘ r ".H vr ' r ,,,-‘ (.14 r4 ' WA I: HI; Lv , I l1 1 I r . .13: ’(7 I I U —‘ J- P\ _ ' . fl 0 511*U1 mar L tn“ .9 t k—7 This netloc of testinx is vzeev on the nrincinle that precticmllv ell systems in the field 0? enfiineer- inq cen he set in :otion hy elternetin: forces of e i (‘1 \ily rerroducihle hv bin (D form. Such forces ere re “:1 ("W 1 L two revolvinr leeees eccentricellv smnprrted end I . novir: in orroeitc directions. is shown tv the dieqrew telow, (ijiudiich the e {VHL solid_(3:rcles ere the }_Jo eccentricclly surpirtod revolvin: ”fRSflf) et inte rel velues of pi for the these Fuele, centrifufiel forces ect in such e “e6 99 to cencel one another. At other values of pi, resultent ection is snow as to produce 9 CUIWIe (3? Tile {jirvn fr)? L. FVflflSE INVGLE' -30.. lmoUClrU VIBRflTIONS H‘- ‘w «a A ~.‘ . f“ v .‘L‘. I v - I' ' . -. 3- 1 imicn iniit enticigflna ei Thi? T£flMltVJDPs(i‘Se&W e electric deter driving, inst_u‘ents to newsure “S D C c+ Q d . frcwniencx; of din: s any? to Furire Tmrver irnn1t tn’;»‘ Drivinfi actor * \, Speci .mn I. AKUeflecto— rxét€?r V\\ \\ \ \ \\ \ \\\ \\ \\\\\\\\‘ I/lj/l/l| .1 I’ll/J 971 do or (c) G E lorsion Test (d) Gimmice ill T011 rive ivnsitf ll of‘IreVQLAWLng rewaens J (D "5 (3 (D T! is C. ‘ "‘ Q < H. .4 3.) __$ "‘3 ...L ; in is v: icrle, os ill- etors have heen built ior frequenCi,s u; to 100 cvcles U Per 3533”“‘3- Umi'l'll'ufiéil forces have been iiw'ctmced of iirom l.- b“,fflh3 poruuis. Eihice inie 1U13t jiSEittETfiled rig ixilbr tr) tine inidgf Tile .etri;nun ivoiuiiite .toIUEe i) 5 produced i£%}frcfortionrl_ixi twc F‘Flifnj’”7 TFCROT of tie svste . For or: rle: in irid eq “n “V“Pfl‘u “*3 J O ('9' ’3 ‘3 C w ‘3 Zn ' ) r—J i + .1 1., 7* 'L—Jo O ,3 VJ. '1 I). “D (1' Si) d (D "3 A) .L‘" {D :1" 7).. CD fl 4" l icum eltwrnetinfi force produced will hecome as high as 40 X 50,000 or 2,000,000 pounds. Procedure With the oscillator rigidly fired to vitreting system, the corresponcinr power innut --.) - v f‘ Ny~ j J“ f ‘1"r‘ '. '1 ['1 ‘J :I .C) V -."I r " a ' 11encgiixater cdirmmvvt to the fflfhl‘l0£*tlfTQF cl‘ tfiis: cifiicfi. 91%: nt1i+m= n11 - _.--4 ‘ l .L 31 ~ ' ~\ ~..— Ta‘ '7- . r . ‘ ' -- ‘ —.. ,. QTOLS. VJJTHLlOiS bros can by _;3_1ncr7 lanc b¢ ~~ "r-~.- WV- . L ‘ i ‘- —, . : m -4. VQJJ Qcflg”£04r3 .Prcc pro-octor igcflcn cl rcccnkpc ‘3 ‘ ‘~' 'v '. ‘ 'l 'V " N WI I. ‘1“ ' V "- . —‘ ' ’ Trcnncncy 1n eaxly antics Ol OOuRt?lCujvn YOUld m .- — w-u'. (x _.'C— 3;, r r- - ‘v - 1‘» . .. l ‘ . -. -\ 7- . 1 icronca WVJJLijfa. l5; .«mxnn,'if {$118 calla, 3t -15 7w3r57_cle o -. ~ ~ r ‘ w ‘ r . “ ‘ ‘ -: ‘ 4. _‘ to lOFTJQdCQ path cl Vibrat arc cl eniivcs Pnn . r" - . r —--— 1 3,: < v - . q - 1 . -‘ - - -. . ~n A» ‘- > I- —~p ,\ xnzeng Icnrcuan; e ‘4F£._fOUJM1 :11 su7l’QUlWJ7li,S '3rfi1'5+3 Cauld we made Fefcnc cc fleticn of ccnctructicn or “,4- ,2 0 fl 0 - .g'l .L 7-. 1-, 3. : _\ _“ 1" (A ‘ . . lntbclluthfl cl hc ~Ccplncry. l?ls ypa bécn cone (— ‘1 -I- '1 1 r' 1. 1 'l - ‘ J‘- - a - '1 - < an 2P7, (I‘CIS one ills. One 01 {im> wiry iicsb 19"nl.|r.t iY-11.=fl t‘“?W1 i‘cricr ctr? iril rrvtirin 01' ii 9 ci‘fivfl‘— hccn n “ *nln -9tt9r to corrnct. Si ilcrly Nari?— .. k L} - 5 .t . GUtFJN, V”?%;1cclc. a r 'tfilW7300F]_ V‘CULU?fiClfi¥E of (xvil- inifi walls, townrs, nnfi founioticnc ccnlc be found. DOWCLKSIOU From stuoies of e number of artiCles on the subject, "Determination of Young‘s nooulus by the sonic Method" the following general statements seem to he indiceted. J U 1. In the derivetion of tne reletionsnin tetween E ena frequency or vibretion, the materiel is assumed perfectly elastic. by the Sonic method, emplituées of Vibration UP to 10“6 incnes per inch are produced, Whisk seems to be sufi loientlr sushi as to remain Witnin the elastic li its for the nsteriel and thus Verify the accuracy of T1? . whet Specimens cen be tested Without destroying, de aging, or otherWise alterinfi the saunle. hence tre (a 6 C)” T“) ’1 < “ :3 be used for nrozressive tests at ell sees. This is conGHCiVe to greater eccurecy OJ results since the rnynber'cyf vars! bles ill'tbfi tweet sergile cer1lme held. to the onenée in the intetuel structure of the been it— o. in the freezing ens thawing tests of concrete, tfle largest cnange in E occurs curing the Iinst few cyCles L l CFC BVQD 3 0f Eood concrete Will slow a oecneeso. Poor Speci e s can usually be fletegtec mjtnjn 20 cycles “MN the 5 of the mood and the bed ereciwens st tnet tine is quite different. Ufliziwe SPQMIE'CO in? :vart nifxwise ijl'the lulilfiijt: heterisl field wtwere 52in? ocours thnu eyeles of free?— L—J. f5 1 fl: :‘3 pi 6+ :3. D H. H VT 3 d U) 0 CD CD :3 O L. similsr cycles. 4. Temperature chon cs have little effect on results. sstureteo or near saturated U ,3 0! IL.) [.4 O ,_J 2’) cf s ’D O 4 k ,5 CD ’3’) ‘ .J :5 Specimen have little effect on tte results. Hence e seturetee condition is Well suited for obteinins center- stive neasurewonts. fine sonic wofiulus is very sensitive to s (ll omen es of moisture in e reletively dry sample. 14‘ 5 Yet unexrlsined - That the oifrererce in or the saturated enfi the dry Specimen is severel ti es ttet cue to the chenge in density, the wofiulus meins frester for tile tset; STV§ClTLQ ,s. 5. That oven drying will cruse e conniooreole cuanze ( in natural frequency. Obert (t-lO) found tnnt His best results were ozteinev when the sample was cured in water, 28 days in air and then dried for 24 hours in en even; this lest step being etsoluteLy necessary. nor testins of stone, two week crying st ordinary room eur- eratures ves suffiCJenp to give consistent results. 1w nrocess troceers, sneciuen toxins to dis— ‘ _.‘ "' 3;) l intefirate ens causes the resonfince DQFK to stresd out, it; brute {is . 01“? crni nmirew ci‘tific. it ‘to E?Cli?0tl fiuidelweniu l frocuency. .UTOKEW} P k'. P k ' I l A. I c — I r _ . I i r ' I . t r O A I ‘I'IPIV 7. tr L ‘ l . . . x . . - I ~ . \ I. I . I _ I _ . . a. . _ m . _ o '| u C D I . ‘ IL. . . - _ n I I t -_ S . .l. a II‘ I I . _ Z. n. _ at M . ..I u .... u . I I. I \ III. II‘ I 0" no! J0.“ _ I. I «I 4.. II I I A . .. - . P O I . . . Q . . .. I. . r I . I. I _. I; I. p .\. . II ._ II . I I I . I .. I I I . I. .1 I. I I I I I I I . v I\ I w v a p ~ h I 0 . .. . L . . I . . .I . I I II I. I' . I! \~ I I I ( a a n _ i u 0\ I J I . I t \ .I‘ t h . OI I I I J I ’ . « I: 5 . ~ I . . I u I \ I p o |.. i I . . I I I .\ Iv WW" 0 ‘P MICHIGAN STATEI UNIVERSITY LIBRARIES LU. 3| ‘1