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Д a = y h - — h = ----- , G GA A b s o lu t s iljis h s iljitu v c h i k u c h va k e s im la r o ra s id a g i m asofaga to ‘ g ‘ ri, k o ‘ n d a la n g kesim yu za va s iljis h d a g i e la s tik lik m o d u lig a te s k a ri p ro p o rs io n a l ekan. G u k q o n u n i absolut s iljis h u ch u n ana shunday ifo d a la n a d i. G u k q o n u n i c h o ‘ z ilis h va s iq ilis h uchun q u y id a g ic h a ifo d a la n is h in i il- g a ri k o ‘ rib o ‘tgan edik; Iz o t r o p m a te ria lla r u c h u n s iljis h d a g i e la s t ik lik m o d u li G b ila n c h o ‘ z ilis h d a g i e la s tik lik m o d u li E orasida m a ’ lu m b o g ‘ lanish m a vju d . B u bogM anishning m a te m a tik ifo d a s in i k e ltirib c h iq a ris h uchun s o f s iljis h h o - Ia tid a g i e lem entni k o ‘ rib o ‘ tam iz. S o f s iljis h n in g o ‘ zi nim a? T e k is k u c h la n is h h o la tid a boMgan p riz m a tik sterjendan m a ’ lu m b u rch a k v a y o ‘ n a lish d a to ‘ g ‘ r i to ‘ rtb u rc h a k s h a k lli shun day elem entar boMakcha a jra tib o lis h m u m k in -k i, unga fa q a t u rin m a ku ch la n is h la r ta ’ sir etadi. N o rm a l k u c h la n is h la r n o lg a teng boMadi. A n a shun day h o la td a , y a ’ ni faqat u rin m a k u c h la n is h la r ta ’ s irid a h o sil boMgan d e fo r m a tsiya s o f siljish deb ataladi (5 .4 -ra sm ). S o f s iljis h m a te ria ln in g h a jm i o ‘ z g a rm a y d ig a n b ir d a n -b ir te k is k u c h la n is h h o la tid ir , b u n d a e le m e n ta r boM akcha faqat sh a k lin i o ‘ z g a rtira d i. E n d i E b ila n G orasidagi bogM anishni a niqlashga o ‘ ta m iz . S o f s iljis h tu fa y li A C dia g on a l AS m asofaga uzayadi (5 .5 -ra sm ): 5.4-rasm. 5.5-rasm F) bu yerda a = S -c o s 4 5 ° = S — ; y = — \ A C = S bo M g a n lig id a n 2 G AS = — S (a) 2 G (Jm umlashgan G u k q onuniga k o ‘ ra n is b iy uzayish q u yid ag ich a y o z ila d i: AS cr. a , s, - — = — - u — , 1 S E E cr, = г va cr3 = - г e k a n lig in i e’ tib o rg a olsak, uzayish (l + jj ) t AS = ±— ^ — S (b ) boMadi. E (a) va (b ) ifo d a la m in g chap to m o n la ri teng boMgani u ch u n o ‘ n g to m o n - la r ham teng boMadi: G = 2 ( l + / / ) ' (5 -5) B u fo rm u la d a g i c h o ‘ z ilis h (s iq ilis h ) e la s tik lik m o d u li E v a Puasson k o e ffits ie n ti ц ta jrib a yoM i b ila n a n iq la n a d i. B u la r o rq a li s iljis h d a g i e la s tik lik m o d u lin i aniqlasa boMadi. 1 3 A g a r Ц = — boMsa, G - —E boMadi. j 8 5.2. Sof siljishda ruxsat etilgan kuchlanishlar R u x s a t e tilg a n k u c h la n is h n i ta n la sh m asalasi s iljis h d a s iq ilis h va ch o ‘ zilishdagiga nisbatan ancha m urakkab. C hunki tajribalarda boshqa x il de- form atsiyalardan x o li boMgan s o f siljis h holatiga erishish ju d a q iy in . Shu saba b li siljishdagi ruxsat etilgan kuchlanishlar nazariy yoM lar b ilan belgilanadi. T e k is k u c h la n is h h o la tid a u ch ta bosh ku ch la n ish d a n b ir i n o lg a teng boMadi (5 .5 -ra sm ). Shunga k o ‘ ra s o f s iljis h d a cr, = r , cr2 = 0, cr3 = - x Ik k in c h i m u s ta h k a m lik nazariyasidan cr, - fio - < [c r ] (5 .6 ) e k a n lig i b izg a maMum. B oshqa k u c h la n is h la r q iy m a tin i (5 .6 )g a q o ‘ y ib , M r < J — L (5 .7 ) 1 + m ga ega b o ‘ la m iz . F o rm u la n in g o ‘ ng to m o n i ru x s a t e tilg a n k u c h la n is h n i if o d a la y d i. Shunga k o ‘ ra ru x s a t e tilg a n u rin m a k u c h la n is h n i q u y id a g ic h a ifo - dalash m u m k in : ( 5 8 ) M e ta lla r u ch u n ц = 0 ,2 5 -0 ,4 2 e k a n lig in i h is o b g a o lsa k, ik k in c h i m u s ta h k a m lik n a za riya sig a k o ‘ ra s o f s iljis h d a g i ru x s a t e tilg a n u rin m a k u c h la n ish q u y id a g i k o 'rin is h g a ega b o ‘ la d i: [ r ] = ( 0 , 7 * 0 , 8 ) [ < r ] (5 .9 ) U c h in c h i m u s ta h k a m lik nazariyasi b o ‘ y ic h a cr, - cr3 < [c r ] y o k i t - ( - r ) < [c r ] asosida q u y id a g i fo rm u la g a ega boM am iz: [c r ] T < -—- = \ t 2 И , (5 .1 0 ) y a ’ n i s iljis h d a g i ru x s a t e tilg a n u rin m a k u c h la n is h [ r ] = 0 , 5 [ o - ] . (5 .1 1 ) T o ‘ rtin c h i (e n e rg e tik ) m u s ta h k a m lik n a za riya sig a m u v o fiq < [ a ] y o k i V t ^ m ^ " + t ^ < [ c t ] . [c r ] B u n d a n : г > ^ = [ г ] . (5 .1 2 ) D e m a k, [ r ] = 0 . 5 7 [ o - ] « 0 . 6 [ < r ] . (5 .1 3 ) T u r li m u s ta h k a m lik n a z a riy a la ri asosida a n iq la n g a n ru x s a t e tilg a n k u ch la n is h la r b ir x il e m a s lig in i k o ‘ rd ik . P la stik m a te ria lla r uchun e n e rg e tik nazari ya b o ‘ y ic h a a n iq la n g a n ru xsa t e tilg a n k u c h la n is h (5 .1 3 ) b oshqalarga nisba tan y a x s h iro q n a tija b e ris h in i a y tib o ‘ tis h jo iz . R u xsa t e tilg a n u rin m a k u c h la n is h m a ’ lu m boMsa s iljis h (q ir q ilis h ) dagi m u s ta h k a m lik sharti q u y id a g ic h a ifo d a la n a d i; < [ r ] , (5 .1 4 ) max a A B a ’ z i m a te ria lla r u c h u n s iljis h d a g i ru x s a t e tilg a n k u c h la n is h la rn in g q iy m a tla ri 7 -ja d v a ld a k e ltirilg a n . 7-jadval. Parchin mix va payvand birikmalar uchun qirqilishga boMgan ruxsat etilgan kuchlanishlar B irik m a tu r i Qirqilishdagi kuchlanish, M p a P a rch in m ix: P o 'la t 20 d a n ta y y o rla n g a n asosiy e le m e n tla r P arm alangan te sh ikd a g i p a rc h in m ix (B s in f) Y o y ilg a n te sh ikd a g i p a rc h in m ix (C s in f) 100 140 100 Payvand: Y u p q a q o p la m a li e le k tro d d a q o ‘ ld a payvandlash Q a lin q o p la m a li e le k tro d d a q o 'ld a payvandlash A v to m a tik payvandlash 80 110 110 5.3. K onstruksiya elem entlarini siljishga hisoblash 5.6-rasm. 1. Parchin mixli birikmalar. T u rli x il ferm a s te ije n la rin i, qozon va sam olyot lis tla rin i b irik ti- ris h d a b o lt v a p a rch in m ix (з а к л ё п к а л а р ^ а п fo y d a la n ila d i. B o ltli y o k i parchin m ix li b irik m a la r s iljis h g a ishlaydigan elem entlar hisoblanadi. Ik k i Iis tn i p archin m ix bilan ulash uchun u la m - in g ik k a la s i ham b ir x ild a te sh ilib , teshiklarga p a rc h in m ix k iy g iz ila d i. U n in g uchi g id ra v lik press y o k i m axsus b o lg ‘ a b ila n p a rc h in la n ib , qalpoq h o s il q ilin a d i (5.6-rasm ). M is o l ta riq a s id a ik k i m e ta ll Iis tn i o ‘ zaro b ir ik tir u v c h i b ir d ona p a rch in m ix n in g ish i b i lan ta n is h ib o ‘ ta m iz (5 .7-rasm ). F k u c h la ri lis tla rn i b ir b irig a nisb a ta n s ilji- tis h g a in tila d i. B u n g a p a rc h in m ix q a r s h ilik k o ‘ rs a ta d i, n a tija d a u lis tla r b o s im ig a u c h ra y d i. P a rch in m ix s irtig a ta ’ s ir e tu v c h i b o s im k u c h in in g q iy m a ti ta sh q i k u c h F ga teng b o ‘ lib , bu k u ch p a rc h in m ix n i q irq is h g a harakat q ila d i. Q ir q ilis h ke sim id a u rin m a k u c h la n is h la r b ir te k is d a ta rq a lg a n deb faraz etsak, u h o l da bu b irik m a u ch u n m u s ta h k a m lik s h a rti q u y id a g ic h a ifo d a la n a d i: 5 .7-rasm. _ F _ Г ~ A ~ 4 F n d 2 < [ r ] yo k i 4 F n d 2 Ф 1 - B u n d a n p a rc h in m ix n in g d ia m e trin i a n iq la s h q iy in emas: S h u n i ham ta ’ k id la s h jo iz k i, F k u c h i p a rc h in m ix n i egishga ham in tila - d i. B ir o q e g u v c h i m o m e n tn in g q iy m a ti k ic h ik b o M g a n lig i tu fa y li u n d a n h o s il boM adigan n o rm a l k u c h la n is h la m i e’ tib o rg a olm asa ham b o M a d i, c h u n k i b u z ilis h aynan q irq ilis h natija sid a s o d ir boMadi. Shunga k o ‘ ra b o lt v a p a rc h in m ix la m i s iljis h g a h iso b la sh a m a liy jih a td a n y e ta rli h is o b la n a d i. A m m o bu yerda p a rch in m ix li b irik m a la m in g m us ta h k a m lig ig a s e z ila rli ta ’ s ir k o ‘ rsatadigan boshqa b ir o m il b o r. U ham boMsa, lis tla m in g parchin m ix s irtig a boMgan ta ’ s irid ir. B u ta ’ s ir natija sid a parchin m ix e zila d i. Ezilish deganda k o n ta k t sirtla rd a vu ju d ga keladigan p la s tik de fo rm a ts iy a tu s h u n ila d i. E z ilis h g a h is o b la s h ham ta q r ib iy x a ra k te rg a ega, c h u n k i, e z u v c h i k u c h n in g k o n ta k t s irti b o ‘ y ic h a ta rq a l- ish q o n u n iy a ti h a m b iz g a a n iq em as. B u k u c h n in g p a rc h in m ix s irti b o ‘ y ic h a ta x m in iy ta rq a lis h q o n u n i 5 .8 - rasm da ta svirla n g a n . R asm ga k o ‘ ra ezuvchi k u c h A n u q tada eng k a tta q iy m a tg a ega boM ib, В va С n u q ta la rid a u n in g q iy m a ti n o lg a teng boMadi. P a rch in m ix s irti b o ‘ y ic h a n o te kis ta rq a lg a n b o s im y a ’ n i yu za b irlig id a g i q iy m a tin i q desak, m u v o z a n a t s h a rtin i q u y id a g ic h a yozsa boM adi: F = h dA (5 .1 6 ) B ir o q q n in g p a rc h in m ix s irti b o ‘ y ic h a ta rq a lis h q o n u n i n o m a ’ lu m b o M g a n lig i u ch u n , b o s im n in g toM iq q iy m a tin i ifo d a lo v c h i in te g ra ln i, in te g ra l boM m agan, am m o shunga teng k u c h li boMgan ifo d a b ila n a lm a s h ti- ra m iz . E z u v c h i b o s im s ilin d r ik s irt b o 'y ic h a em as, p a rc h in m ix n in g d ia m e tra l k e s im i b o ‘ y ic h a te n g ta r qalgan deb fa ra z e ta m iz (5 .9 -ra sm ). B u h o ld a (5 .1 6 ) ifo d a q u y id a g i k o ‘ rin is h n i o la d i: 5.8-rasm. in te n s iv lig in i, F = jqdA - (J„A3J, (5 .1 7 ) bu ye rd a crez - p a rc h in m ix n in g d ia m e tra l k e s im id a g i e z u v c h i k u c h la n is h ; A ez - p a rch in m ix n in g d ia m e tra l k e s im y u z a s i, Aa = S d ; d - p a rc h in m ix d ia m e tri; 6 - p a rc h in m ix s ir itig a e z u v c h i b o sim b e ra y o tg a n lis tn in g q a lin lig i; (5 .1 7 ) d a n e z ilis h k u c h la n is h i a n iq la n a d i. F E z ilis h u c h u n ru xsa t e tilg a n k u c h la n is h n i [c r ,.] desak, e z ilis h d a g i m us ta h k a m lik s h a rti q u y id a g ic h a ifo d a la n a d i: (5 .1 9 ) E z ilis h u c h u n ru xsa t e tilg a n k u c h la n is h c h o 'z ilis h (s iq ilis h ) d a g i ru xsa t e tilg a n k u c h la n is h d a n ka tta ro q o lin a d i: [ (5 .1 9 ) b o ‘ y ic h a aniq la n g a n d ia m e tr e z ilis h d a g i m u s ta h k a m lik s h a rtin i q a n o a tla n tira d i: H a m s iljis h , ham e z ilis h b o 'y ic h a m u s ta h k a m lik s h a rtla ri q a n o a tla n tiri- lis h i u c h u n , d ia m e tr qaysi shart b o ‘ y ic h a k a tta c h iq q a n boMsa, o ‘ shanisi q a b u l q ilin a d i v a standartlarga m oslab y a x litla n a d i. B o lt y o k i p a rc h in m ix u ch u n lis tla r i я j h l j h l te s h ilg a n d a k e s im z a ifla s h ib q o la d i. ^ -------i § T ~ S h u n in g u c h u n u la n u v c h i lis t la r j U c h o ‘ z ilis h g a y o k i s iq ilis h g a te k s h ir ib Ш k o 'r ila d i. О О 1 I Anetw Abmtto U la n u v c h i lis t n in g I - I k e s im id a g i 1 1 y u z a n i A nett0, 11-11 k e s im id a g i y u z a n i 5.10-rasm. A brutl0 d e b b e tg ila s a k ( 5 .1 0 -ra s m ), c h o ‘ z ilis h ( s iq ilis h ) d a g i m u s ta h k a m lik sh a rti q u y id a g ic h a y o z ila d i: F r i ° — A— - И . (5 .2 0 ) nctro B u y e rd a F - u la n u v c h i lis tla rn i c h o ‘ z u v c h i k u c h ; [cr] - c h o ‘ z ilis h uch u n ruxsat e tilg a n k u c h la n is h Anellu= ( e - 2 d ) S . 2. P ayvand birikmalar. K o n s tru k s iy a e le m e n tla rin i b ir ik t ir is h uchun p a rc h in m ix la r is h la tis h X I X a s m in g b o sh ida n bo sh lan g a n b o ‘ lsa, asr o x ir i- ga k e lib u n in g o ‘ m in i asta-sekin p a y v a n d la s h e g a lla y b o s h la d i. K e y in g i p a y tla rd a p a rc h in m ix la rd a n fo y d a la n is h d o ira s i a n ch a k ic h ra y g a n : e n d ilik - da p a rc h in m ix la r, asosan, y u q o ri harorat o stid a boM adigan va d in a m ik k u ch - . F \ 1 1 в (г 1 . ) 5 = 8 м м р к 60-70? б :: Т> ; = ( 1 0 - 1 б ) м м la r ta ’ s irid a is h la y d ig a n k o n s tru k s iy a la rd a (m a s a la n , s a m o ly o ts o z lik d a , k o ‘ p rik la rd a ) is h la tila d i xo lo s. P ayvand b ir ik m a la m in g bu q a d a r k e n g ta r q a lis h in in g s a b a b i, u n in g p a rc h in m ix li b irik m a la rg a nisbatan q a to r a fz a llik la rg a ega e k a n lig id a d ir. A v v a la m b o r y e ta rli darajada m u s ta h k a m lik k a ega. B u n d a lis tla r te s h ilm a y - d i, dem ak ham m a te ria l te ja la d i, ham b ir ik tir is h te x n o lo g iy a s i soddalasha- d i, k o n s tru k s iy a y e n g illa s h a d i; c h o k la r z ic h b o M g a n lig i tu fa y li suv va gazni 0 ‘ tka zm a yd i. P a yva n d la sh is h la ri e le k tr y o y i asosida amalga o s h irilib , asosan ik k i usulda b a ja rila d i: a) u c h m a -u c h payvandlash; b) ustm a-ust payvandlash. U la n a d ig a n lis t la r b i r te k is lik d a y o ts a u chm a-uch u la n a d i (5 .1 1 -ra sm ). B u n d a u la n a d ig a n lis t la r o ra s i e r itilg a n m e ta ll b ila n to M d irila d i, m e ta ll s o vig a ch , p a y v a n d c h o k h o sil boMadi. C h o k la r ulanadigan lis tla m in g q a lin lig ig a qa ra b , 5 .1 1 -ra s m d a k o 'rs a tilg a n s xe m a la rn in g b ir i k o ‘ rin is h id a am alga o s h iri- ladi. K o ‘ nda lan g c h o k n in g c h o ‘ z ilis h v a s i q ilis h b o ‘ y ic h a m u s ta h k a m lig i q u y id a g i fo r m u la y o rd a m id a te k s h irila d i: a = ■ (5 .2 1 ) B u yerda 8 1 = A, - c h o k n in g s h a rtli ish y u z a s i, £ = b - \ . 0 m m c h o k n in g h is o b iy u z u n lig i, d - u la n a d ig a n lis tn in g q a lin lig i. B a ’ zan te x n o lo g ik y o k i k o n s tru k tiv sa- bablarga k o ‘ ra ulanadigan lis tla m i ustm a- ust q o ‘ y ib payvandlashga to ‘ g ‘ ri ke la d i. P a yva n d la s h n in g b u u s u lid a p a y v a n d c h o k la r c h o ‘ z u v c h i k u c h g a n is b a ta n k o ‘ ndalang ( 5 . 12-rasm , a) y o k i b o ‘ y la m a (p a ra lle l) h o la td a ( 5 . 12-rasm, b) jo y la s h i- s h i m u m k in . C h o k b ir in c h i h o ld a k o ‘ ndalang y o k i v a lik s im o n deb, ik k in c h i h o ld a b o 'y la m a y o k i y o n b o s h c h o k deb ata la d i. U c h b u rc h a k k o ‘ rin is h id a g i c h o k n in g b is s e k trik y o ‘ n a lis h id a g i k e s im i z a if h iso b la n a d i, c h u n k i c h o k la rn in g y e m ir ili shi ana shu kesim d a n b o sh la n a d i. 5 .12-rasm. 5.11-rasm. ± _ ^ Л - T h = 0 ,7 8 S h u n in g u c h u n ham h iso b la sh d a aynan shu k e s im n in g m u s ta h k a m lig i te k s h irila d i. A B k e s im n in g h is o b te n g la m a si q u yid a g ich a y o z ila d i. F г - — V a lik s im o n c h o k i k k it a b o M g a n i u c h u n y u z a ik k ig a k o ‘ p a y tirilg a n . A g a r A = lkS c o s 4 5 ° = 0 .7 /*<5 e k a n lig in i in o b a tg a o lsa k, x a v fli k e s im n in g m u s ta h k a m lik sh a rti q u y id a g ic h a ifo d a la n a d i: B u ye rd a k o ‘ n d a la n g c h o k u z u n lig i l K = в - 1 0 т т - deb q a b u l q ilin a d i. A m a liy o td a y o n b o s h ( b o ‘ y la m a ) c h o k la r k o ‘ p is h la tila d i. L is tla r u stm a- ust q o ‘y ilg a n b irik m a la rd a y o n b o s h c h o k la r m u s ta h k a m lig i ham (5 .2 2 ) fo r m u la b ila n t e k s h ir ila d i. F a q a t b u y e rd a b o 'y la m a c h o k u z u n lig i £s = £ - \ 0 m m deb o lin a d i. 5.1-misoI. Parchin mix yordam ida biriktirilgan ikki list F =8kH kuch bilan torliladi. (5.13- rasm,a). Listlarning qalinligi d = 8mm, siljish uchun ruxsat etilgan kuchlanish [ r ] = 60 M P a , ezilishga ruxsat etilgan kuchlanish [стю ] = 200А Й Р а. Birikmaning mustahkamligi hisoblansin. Y e c h is h . P a rch in m ix d ia m e trin i m u s ta h k a m lik shartidan to p a m iz (5 .1 3 ); L is tla rn in g p a rc h in m ix g a te g ib tu rg a n s irtin i e z ilis h sh a rti b o ‘ y ic h a te k - sh ira m iz. L is tn in g p a rc h in m ix b o s im id a n e zila d ig a n s irti y a rim s ilin d r shak- lig a ega (5 .1 3 -ra sm , b). t = (5 .2 2 ) bundan - d 4 с Y a rim s ilin d rn in g b a la n d lig i §, d ia m e tri d. B o s im n i y a rim s ilin d r s irti b o ‘ y ic h a ta rq a lish q o n u n i bizga nom a’ lu m ; am m o u p a rch in m ix b ila n lis t o ra lig ‘ idagi tu rli nuqsonlarga hamda m aterialga b o g ‘ liq e k a n lig i ayon. H iso b n i sod d a la sh tirish m aqsadida bosim y a rim s ilin d r s irtig a emas, shu s irtn in g d ia m etral te k is lik d a g i proeksiyasiga, y a ’ ni dd yuzaga ta ’ s ir etadi, deb o lin a d i. Shunday q ilib , list teshigi devorlaridagi e zilish ku ch la nish i quyidagiga teng: F 8 0 0 _ „ H =■ = 7 6 9 2 ,3 - S d 0 .8 -1 .3 sm ' T o p ilg a n ku c h la n is h ruxsat e tilg a n k u c h la n is h d a n kam c h iq d i, dem ak e z ilm a s lik sharti q a n o a tla n tirila d i. 5.2-misol. Burchaklikni list- g a tutashtirish, uchun zaru r bo ‘Igan parchin mixlar soni an iqlansin (5,14-rasm). Qo'yilgan yuk F=75kH. Parchin mix d i ametri d = 1,7sm; [o]=140,0MPa; [ t ] = 110,0 MPa, [a , .] =280,0 MPa. L ist va burchaklikning uzilmasligi ham tekshirilsin. Boshqa о 'Ichamlar shaklda berilgan. Y e c h is h . P archin m ix la m in g k e s ilm a s lik s h a rtid a n : F 5 .14-rasm. n > E z ilm a s lik shartidan; n > , H F n d 2 n = 3 . n - 2 . KT U c h ta p a rc h in m ix q o ‘ y a m iz . B u rc h a k lik b ila n lis tn in g u z ilm a s lik s h a rtin i te k s h ira m iz ; B u rc h a k lik n in g k o ‘ ndalang kesim yu za si As = 9 , 8 7 s m 2. L is tn in g k o ‘ ndalang kesim yuzasi A = 8 ,0 T , 2 = 9 ,6 s m 2 c r, = — = 8 8 ,0 M Pa < [c r ] > As S d A1 - S d D e m a k , m u s ta h k a m lik ta ’ m in la n g a n . © ' О О 5 .15-rasm. 5.3-misoL Kengligi b = 27 sm, qalinligi 5 = 1,6 sm bo'lgan ikki list diam etri d = 2,5 sm bo'lgan 8 ta parchin mix bilan ustma-ust biriktirilgan (5,15-rasm). Bu birikma- ning xavfsizligi t a ’minlangan holda 1* listlarga qo'yilishi mumkin bo'lgan kuch (F) ning eng katta qiymati topilsin. Listlarning mustahkamligini parchin mixlar necha foizga pasayti- radi? Ruxsat etilgan kuchlanishlar; [ а ] = \2 0 ,Ш Р а -, [ r ] = 8 0 ,0 M P a; [стз, ] = 2 4 0 ,0 M P a . Yechish: F k u c h in in g q iy m a tin i, p a rc h in m ix la r o ‘ m a tila d ig a n ke s im - la m in g m u s ta h k a m lik sh a rtid a n a n iq la y m iz . 0 F} - \ a \ - { b - 2 d ) S - 4 2 2 ,4 к Н C h o ‘ z u v c h i ku ch F p a rch in m ix la rg a b ir x il ta rq a lm a y d i. M asalan, ik k in c h i qatordagi p archin m ix la rg a b irin c h i qatordagiga qaraganda ozroq y u k tushadi. Odatda, ik k in c h i qatordagi p a rch in m ix la r k u c h n in g 0,75 q ism in i qabul q ila d i. S huning uchun ham, ik k in c h i q a to r p a rch in m ix la ri o ‘ m atiladigan kesim n in g m u s ta h k a m lik shartini tu zish d a k u c h n in g 0,75 q is m i o lin a d i: 0 ,7 5 - F 2 = [ ( j ] - { b - 4 d ) S \ F2 = 4 3 5 , 2 кН. 2 ) P a rch in m ix la m in g q irq ilis h g a q a rs h ilik k o ‘ rs a tis h shartidan: F3 = Download 78.98 Kb. Do'stlaringiz bilan baham: 
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