(i) ix 1 1 1.1 1 1.24 1.35 1.46 1.4.1 6 1.4.2 6 1.4.2.1 6 1.4.2.2 8 1.4.3 8 1.4.4 8 1.4.5 10 1.5 12 1.6 12 2 15 2.1 16 2.2 18 2.3 20 2.3.1 20 2.3.2 23 2.3.2.1 23 2.3.2.2 24 2.3.2.3 26 2.3.3 Griffith 27 2.3.4 Griffith 29 2.4 35 2.4.1 35 (ii) 2.4.2 38 2.4.3 42 2.5 K G44 2.6 49 2.7 51 2.8 56 2.8.1 56 2.8.1.1 Westergaard56 2.8.1.2 Muskhelishvili60 2.8.1.3 Williams60 2.8.2 61 2.8.3 64 2.8.4 66 2.8.4.1 70 2.8.4.2 K75 2.8.5 79 2.8.5.1 K 80 2.8.5.2 K 81 2.8.6 86 2.8.6.1 K86 2.8.6.2 K87 2.8.7 88 2.8.8 90 2.9 91 2.9.1 92 2.9.2 93 2.9.3 94 2.9.3.1 Irwin94 2.9.3.2 100 (iii) 2.10 102 2.11 104 2.11.1 CTOD Irwin105 2.11.2 CTOD 1062.12 109 2.13 110 : Williams113 3 -125 3.1 125 3.2 J-128 3.2.1 128 3.2.2 J 131 3.2.3 J 133 3.3 J - CTOD134 3.4 J 137 3.4.1 J 137 3.4.2 J 148 3.4.2.1 148 3.4.2.2 151 3.4.2.3 164 3.4.3 EPRI166 3.4.4 1703.5 J 175 3.5.1 J-175 3.5.2 J 178 3.6 181 3.7 182 : Jpl EPRI 185 : J-integral estimation for a semi-elliptical surface crack in a round bar under tension193 (iv) 4 197 4.1 197 4.2 199 4.3 201 4.3.1 201 4.3.2 202 4.3.2 202 4.4 206 4.5 214 4.5.1 214 4.5.2 214 4.5.3 217 4.5.4 219 4.5.5 220 4.5.6 221 4.6 KIc223 4.7 KR234 4.8 JIc244 4.8.1 245 4.8.2 255 4.9 JR262 4.10 JR 267 4.10.1 EPRI268 4.10.2 268 4.11 CTOD272 4.12 277 4.13 278 4.14 278 : 281 (v) 5 295 5.1 295 5.2 297 5.2.1 299 5.2.2 299 5.2.3 299 5.3 301 5.3.1 da/dN 302 5.3.2 da/dN incremental polynomial302 5.3.3 da/dN modified difference303 5.3.4 da/dN central difference304 5.4 308 5.4.1 309 5.4.2 309 5.5 311 5.5.1 311 5.5.1.1 311 5.5.1.2 313 5.5.1.3 313 5.5.2 314 5.5.3 317 5.6 318 5.6.1 318 5.6.2 320 5.7 321 5.7.1 323 5.7.2 323 5.8 327 5.8.1 327 5.8.2 328 (vi) 5.8.3 Simplified Rainflow334 5.8.4 339 5.8.4.1 340 5.8.4.2 Wheeler341 5.8.4.3 Wheeler 343 5.8.4.4 Willenborg343 5.8.4.5 346 5.8.4.6 346 5.9 347 5.10 -349 5.11 353 5.12 357 5.13 357 : 363 : 375 6 381 6.1 381 6.1.1 381 6.1.2 SCC383 6.1.2.1 384 6.1.2.2 384 6.1.3 387 6.2 389 6.2.1 389 6.2.2 391 6.3 395 6.3.1 C*396 6.3.1.1 C* 397 6.3.1.2 C* EPRI399 6.3.1.3 C* 401 (vii) 6.3.1.4 C* 402 6.3.2 403 6.3.3 407 6.4 410 6.5.1 412 6.5.2 412 6.5 414 6.6 415 : 419 7 425 7.1 425 7.2 425 7.3 427 7.3.1 427 7.3.2 428 7.3.3 431 7.3.4 435 7.4 CTOD438 7.5 441 7.5.1 441 7.5.2 J-445 7.6 R6448 7.6.1 449 7.6.2 451 7.6.2.1 451 7.6.2.2 451 7.6.2.3 452 7.6.2.4 453 7.6.2.5 454 7.6.2.6 Lr455 (viii)7.6.2.7 Kr455 7.6.2.8 458 7.7 472 : WES 2805-1997473 479 (ix) (simulation) 7 123 - 4 56 7 R6 EmeritusProf.Dr.YasuhideASADA (), Assoc. Prof. Dr. ToshiyaNAKAMURA (x) Prof.ShinsukeSAKAI TJTTP-OECF .. Jirapong.K@Chula.ac.th 2553 (xi) stress intensity factor +++ singularity dominated-zone + + fracture toughness 1 1.1 1 (overload)(fatigue)(creep)(corrosion) (wear)(buckling)(failurecriteria) ()( )( )()() (failureanalysis) 2(1) () f( ) g 1 2failure damage corrosion damage corrosion failure 2 ( )( ) ,... f ( ) ,... g >b ()2a (6) aA2 (7) (7)(=0) (infinitely sharp) ! 20 () [7] ( ) 0 > (7) 2.3. ..1921A.A.Griffith (globalanalysis) 2.3.1 (conservationofenergytheorem) (externalwork)W (strain energy) U U W = (8) WP (load-line displacement) LL LLPd W= (9) 4 LLP W 21= (8) LLP U 21= 5 (strain energy density) Ud 21 E221 dxdydzEU221 = (10) 21 WPLLLLP 4 - U 5 - (central through-crack plate) 2a P 6 PLL (stiffness) 2aPPLLLL1 6 22 WUWs dA dAdWdAdUdAdWs+ = ( )dAdWU WdAds= (11) (11) (fracture criteria) (total potential energy) W U = (12) (11)

dAdWdAds= (13) ..1956Irwin(13) (11) (energy release rate, G 2) (crack driving force) (crack growth resistance, R) dAddAdUdAdWG = = (14) dAdWRs= (15) R G = (16) (16) GR(dA dG dA dR ) 2 Griffith 23 dAdRdAdG>(17) dAdRdAdG2c a 12 sin 2c cos 2c ( A) cos a API 579 [3] 2 1 [5()] [5()] (equivalent crack length, 2ceq) (1) ()[5()] (equivalent crack depth, aeq) 42912c 2 cos aa 2 1 cos a cos 2c sin 2c A 4 WES 2805-1997 12c 2c 21212eqc 2() () () 5 API 579(1 20 ) () () () ( o45 ) 430 ceq aeq1. (biaxiality ratio) B (1) 12= B (1) 1 20 (1 0 B ) 2. eqc45 1 ( ) sin2cos sin 1cos2 2BBcceq++ = (2) 45 > 2 ( ) 22 22sin2cos sin 1 cos++ =BBB cceq(3) 3. eqa 3.1 ceq

6() ( ) cos0a a =3.2 W= W W 1(4) 7 12 6 10 5 8 4 63 5 2 4 510 8220 . 1 10 5751 . 4 10 4977 . 4 10 0688 . 210 4141 . 3 10 5471 . 1 10 0481 . 1 99999 . 0 + + + + + = W(5) 3.3 eqa W a aeq 0= (6) ta0a0Wa () () 6 API 579 431 (branched cracking) 7 [7()] W 1.2 ( 8)7.3.3 9 K 9() (coplanar crack) K K 2a 1 12c 212c 2()()12eqc 2() 7 t02 . 1 a aeq =0a ()() 8 432AB1B (s)9()(non-coplanarcrack) (crack shielding) 7() 2 (non-coplanarcracks)(coplanarcracks) 7.1 7.2 API 579 a 2saK 00.20.40.60.81as21 2 3 4a 2sa 2aK 11.11.21.31.41.5as20.5 1 1.5 200 A BA B ()() 9 K [4] 433 7.1 API 579 2c12c2s12c 1 2 1s c c + 2c 2c12c2s1s2 1 2 1s c c + 2 2 1s c c + 2c1+2c2+s2 434 7.2 API 579 2c12c2a2a1s2 2 2 1s c c + 2 2 12 2 2 s c c c + + =[ ]2 1, max a a a =2c12c22a22a1s3 3 2 1s a a + [ ]2 12 , 2 max 2 c c c =3 2 12 2 2 s a a a + + = 2c12c22a22a1s2 2 2 1s c c + 2 2 12 2 2 s c c c + + =[ ]2 12 , 2 max 2 a a a =2c12c22a22a1s2s3 2 2 1s c c + 3 2 1s a a + 2 2 12 2 2 s c c c + + =3 2 12 2 2 s a a a + + =2c22a2a1t s32c1 3 2 1s a a + [ ]2 12 , 2 max 2 c c c =3 2 12 s a a a + + =2c22a2a12c1s2s3 2 2 1s c c + 3 2 1s a a + 2 2 12 2 2 s c c c + + =3 2 12 s a a a + + = 4357.3.4 1 ( ) 7.3 1 dd 0.2t 2 2K ( ) 7.3 API 579 2c0d2a0ta2c :2 . 0 < t d :d c c 2 2 20 + =d a a + =022c0a0 td t2ct2c :8 . 00> t a :( )0 02 2 2 a t c c + = 1 R6 recharacterization 436 1 2 Pa 2,500Pm3,500(E1) 7.2 1) K =Waa K sec a 2) 50m MPa3)( )8 . 2 510 5 KdNda =./ K m MPa4) W t 150 . 5 . 5) 2c1 10 . 2c2 13 .6) ( x1, x2) 65 . 52 . 2c22c1Pm, Pax1x2Ws2 E1 2 5 . 212 1 2 1 2= = c c x x W s. 5 . 11 5 . 6 52 1= + = + c c. 437 2 1 2c c s + > 7.2 N 1 2 c1, c2 s 7.2 31)( K )2)3) 3 ( ) ( ) ( ) ( )2 2 1 1 2 1 2 2 1 1c c c c x x W c c c c + + = + + + (E1) N (E1) N () 1c () 2c () N 10,0000.3270.48612.31320.687 N 50,0002.0093.12816.63716.363 N 45,0001.7582.71715.97617.024 N 48,9891.9573.04316.50016.500 Nmerge 48,989 cmerge ( ) ( ) [ ] s c c c c cmerge+ + + + =2 2 1 12 2 2 221 ( ) ( ) [ ] 500 . 16 043 . 3 2 13 957 . 1 2 1021+ + + + =75 . 24 =. cc cccKWcc = secmax 438ccca mKWccWtP P= + sec22 cc 45 . 37 =cc. c mergec c = 5 . 0 ;25 . 0 ; 22Y YY Y (8) 439kYYa 11 CTOD WES 2805-1997 [2] >= 0 . 1 ; 5 980 . 1 ;22Y YY Y (9) WES 2805 CTOD 1. 2. (effective crack size)a3. 3.1 1 3.2 (welding residual stress) 2 3.3 3 4. CTOD 5. CTOD c c 2 3 440 2(buttweld) 1 E1 200 MPa 2 . WES 2805 1) 2) Y 685 MPa 3) CTOD c 0.05 . 3840305200 MPa E1 1: : 2 : : 47 . 6 = a. 3 : 3.1

496110 662 . 910 20710 200 == =E 4413.2 4960210 618 . 610 20710 6852 . 0 2 . 0 == =E3.3 2.2 15 . 1 =tK 230 = tKMPaY(strain concentration factor)15 . 1 = =tK K ( ) ( )4 41 310 449 . 1 10 662 . 9 15 . 0 1 = = = K 33 2 110 773 . 1 = + + = 4 39610 309 . 310 20710 685 == =EYY536 . 010 309 . 310 773 . 133==Y 1 ( ) 0097 . 0 536 . 0142247 . 6 10 309 . 322 320= == aY . 5 c

c 0.05 . c 7.5 7.5.1 DowlingTownley [6] ( LEFM) 442 c ( )u cW a D = (10) ( ) W a D u (ultimate tensile strength) f ( ) W a f aKmatf = (11) Kmat ( KIc Kc ) f(a/W) (10) uc ( )u ucD = 0 (12) (10) (11) (12) ( )( )umatucf fDW a f aKP= 0(13) ( )( )uuucc uDW a DP= 0(14) a (13)Pf [f(a/W)1](14) Pu 1 a W ( a/W 1) Pf Pu (13)(14) 12 a1a2 a1a2 443u fP P ,aa11a2PfPu 12 Pu Pf ( ) Dowling et al. cP P c fP PP Pf Pc P=Pf P=Pc1 cP P c fP PcP P 45 cP P1 13 cP P1c fP P 1 (16) 13 444Dowling Townley 13 P c fP P cP P 13 () ( 2a ) Heald, Spink Worthington [7]

( ) =228exp arccos2a W a fKumatu (15) c fP P cP P =228exp arccos2cfcPPPP (16) 13 Harrison [6] Dowling Townley f matrPPKKK = (17) LrPPL = (18) Harrison( )Y u + =21 PL(uPc) Pc (16) PL (17) (18) =228exp arccos2rrrKLL(19) 2 122sec ln8=r r rL L K(19) 445 (19) Lr Kr (failure assessmentdiagram,FAD)14 Kr Lr 1) K K 2) Kmat 3) Kr (17) 4) PL 5) Lr (18) 6) ( )r rK L , 7) 7.5.2 J- (19) (14) strain hardening 10.80.60.40.200.25 0.50 0.75 1rLrK( )r rK L , 14 446 Kumar [8]J- Jr K Kr JJJelr= (20) K J-integral Jr Kr r rJ K = (21) 3 2a - (pl ) nY Ypl= J- Kr Lr

1. 2. J- EPRI (20) (21) ( )( ) ( ) a J a Ja JKpl eff elelr+= a aeff ( ) ( )( )( )( ) a Ja Ja Ja J a JKelplelpl eff elr+ += 11(E1) (A4) 3 111+ =nLY Y plPPhWaa J L rP P L= 111+ =nr Y Y plL hWaa J (E2) 447 (14) 3 EKJel2= (E3) 2.4 ( 2) K Tada + =4 206 . 0 025 . 0 12sec4 WaWaWaWaW BPK (E4) PL [ (A5.2) 3] ( )Y LB a W P = 2 (E5) (E4) Lr ( )+ =4 206 . 0 025 . 0 12sec42WaWaWaWaW BB a WL KYr (E6) (20), (21) (22) (19) ( )24 2 2 2 21106 . 0 025 . 0 12sec44111+ + =+WaWaWaWaWa WELL hWaaKY rnr Y Yr 22 21106 . 0 025 . 0 12sec 111+ +=WaWaWaWaL hKnrr FAD a/W0.5Y=60ksi,E=30x103ksi - =1.12,n=10 E1 4480.5 1.0 1.5rL0.20.40.60.81.0rK J- (19) E1 7.6 R6 R6 [1]CentralElectricityGeneratingBoard(CEGB).1976 ( 7.5) R61)2) 3) (margin of safety) 4) (sensitivity) R6 ( 1) R6 1) 2) 3) (buckling) 4497.6.1 R6 15 1 ( 7.6.2.1) 2 ( 7.6.2.2 ) 3 FAD ( 7.6.2.3) 4 ( 7.6.2.4) 5 ( 7.6.2.5) 6 ( 7.6.2.2 ) 7 8 Lr ( 7.6.2.6) 9 Kr ( 7.6.2.7) 10 (Lr,Kr)FAD 11 ( 5 6) 12 (loadreservefactor) [9] ( 7.6.2.8) 13 R6 1) 2) 3)FAD4) 4501. 2. 3. 4. 5. 6. KIc, Kc, K0.26. K0.2, Kg6. K0.2, Kg K7. a07. a0 ag7. a0 a(i)8. Lr9. Kr10. (Lr,Kr ) FAD 11. 12. : 13. 1 2 313. 13. FAD 13. 15 R6 4517.6.2 7.6.2.1 LrKrFAD 3 - ( FAD J-) 7.6.2.2 ) ( FAD ) 1) Y (lower yield stress) (proof stress) 0.2% (uniaxial tensile test) 2) u - 3) ( ) 2u Y +4)E ) () 1) KIc 2) Kc 3) K0.2 0.2 . 4) K0.2/BL 0.2. J-a( BLJ/ 2 . 0 E J KBL BL / 2 . 0 / 2 . 0= ) 5) Kg ga J- 4526)K(a)a Kg R6 Kmat Kmat 7.6.2.3 3 1 : ( )R6 ( ) ( ) [ ]> + =maxmax 6 2; 0; 65 . 0 exp 7 . 0 3 . 0 14 . 0 1r rr r r rrL LL L L LK (22) maxrL YrL=max(23) 2 : >+=maxmax2 13; 0;2r rr rrefY rY rrefrL LL LELLEK(24) ref ref - (true stress-strain curve)Y Y /E 1) (0.2% )2) 3) - 1 453 3 : J- J- Jr ( 7.5.2) >=maxmax; 0;r rr relrL LL LJJK (25) 7.6.2.4 1) 7.3.12) 3) 4) 3 1) 2) 3) 13 K 7.6.2.7 3 1) 2) BS PD6493 ASME XI( BS K 20ASME K 6 ) 3) K 9 R6 2() R6 2 2 454 [ 16()] = c 2 d c a + +0 02 2 04c (28) d a a + =02 (28) d c a c + + =0 02 2 2 (29) d a a + =02 (29) [ 16()] = c 2 d c a + +0 02 04c (30) d a c c + + =0 02 2 (30) 7.6.2.5 R6 3 1 KIc, Kc, K0.2 K0.2/BL 2 K0.2 , K0.2/BL Kg 3 K0.2, K0.2/BL , Kg K(a)2a02c0ad2ca02c02c) ) d 16 4557.6.2.6 Lr

Lr LprPPL = (31) Pp PL LprL= (31) p L 7.6.2.7 Kr K Kr matIrKKK = (32) KI K 1 Kmat KK, pKK , sK p s (32) srpr rK K K + = (33) prK K srK K 1 K prK srK ( )matpI prKa KK0= (34) ( )( )00aKa KKmatsI sr + = (34) a0 Kmat KIc, Kc ,K0.2 K0.2/BL

(plasticity correction factor) 456( )< < =rr rrLL LL05 . 1 005 . 1 8 . 0 05 . 1 48 . 011 (35) ( )( )( )< + Kmat Keff (41) KIIc < Kmat + =122 IIIf ef effKK K (41) 232 22 2 2 2 2 218 28 1288 6 2++ + + + +=II III I I II I II I If efK KK K K K K K K KK466 . 0 IIIKK(41) 7 . 0IIf efKK = 466 . 0 1.050 = YZY ZB B rArBLLLF = (44) LrB < 0.8 [ 18()] LrA > 1.05 [ 18()] (44) OB OA 459rKrL11OBA0rKrL11OCA0rKrL11OA0DABA OOBFL=A OB OFL=ABA OB OFL=() ()()A 17 () () () 11A0LrKrsrKOLr= 1.05 Lr= 0.8XYZBLrALrB () 18 46011A0LrKrsrKOXYZBLrALrBLr= 1.05 Lr= 0.8 () LrB < 0.8 11A0LrKrsrKOLr= 1.05 Lr= 0.8XY,ZBLrALrB () LrA > 1.05 18 () 1 FL[19()][19()]FLA FL20FL (19) (marginofsafety)(aD-aC) 461 (KD-KC)FL FL,allow20 (19) 2 FL0 Kmat = K0.2 FLg Kmat=Kg 1 . 1 LgF2 . 10 L LgF F 1FLAAB1FLAABaAaBKAKBFLFL ()() 19 FL () () 1FLAAB1FLAABKDKC CDaC aDDC FLFLFL,allowaB- aAFL,allowKA - KB 20 FL FL,allow 462 3 FL 21 2 a01 FL a01, a01+a1, a01+a2 a02, a03, A, B, C FL01a02a03aA2a 11a BC 21 FL 4 ( ) ( ) 26 . 0 , 40 . 0 , =r rK L (19) (18) OB r rL K40 . 026 . 0= OB 2122sec ln840 . 026 . 0=rr rLL L 966 . 0 =rL628 . 0 =rK OB 152 . 1 966 . 0 628 . 02 2= + OA 477 . 0 40 . 0 26 . 02 2= + FL 42 . 2 477 . 0 152 . 1 = 4635 [10] t3. E1 E1 1 R6 W2cat E1 E1 (.) a 2c W(.) Pcr

(.) 10.804.0015.209,336 21.105.0015.207,759 31.105.8015.107,238 41.407.5019.608,556 51.407.2018.407,700 61.709.0019.107,883 71.707.5018.506,905 4641.M300grademaragingsteel Yu 215 230 /.2 Kc = 415.05 /.3/2

2. K FQaK =( ) ( ) [ ] g f f t a M t a M M Fw 4322 1+ + =( ) c a M 09 . 0 13 . 11 =( )122 . 0 89 . 0 54 . 0+ + = c a M( ) ( )24 131 14 65 . 0 5 . 0 c a c a M + + = ( ) [ ]412 2 2sin cos + = c a f =taWcfwsec( ) [ ]( )2 2sin 1 35 . 0 1 . 0 1 + + = t a g( )65 . 1464 . 1 1 c a Q + =3. L [4] + =c tt aY L11 5 . 2222230 215=+ /2 tWPcr= LrL= K crKKK = K, Kr, Lr 465K ) ( m MPaKrL ) (MPaLr 1102.580.7971883.51.066 2102.570.7971757.00.950 3102.260.7951728.40.907 4112.710.8761561.80.914 5106.630.8291571.70.870 6128.761.0001391.60.970 7105.030.8161444.70.845 (23)maxrL04 . 1 215 / 5 . 222 =(Lr,Kr) E2 R6 FAD 1 0.51.0rKrL0.5 1.0 0maxrL E2 FAD 1 R6 466 6[11] M4E1 A155 2R 711. 23.6 . GPa E 8 . 190 = ,MPaY3 . 230 = MPau4 . 545 = JR;( ) ( )mc Rc C J c J + = JcJ- 206.5 kJ/m2, C m 185.4( kJ/m2) 0.31 c() 37 . 0 = 2 PP2RoRit E1 1. KF Rt RMKmm = 2(E1) + + =24 . 4 5 . 16422 . 2 5967 . 4 1A F (E2) =20 10 ; 0 . 3 4 . 010 5 ; 25 . 0 125 . 025 . 025 . 0tRtRtRtRAm mm m(E3) Rm , t 2. (limiting moment) =2sin2cos 42 Y m Lt R M (E4) 4673. n Ramberg-Osgood YE002 . 0= (E5) 3 2318 . 0 660 . 0 666 . 0 324 . 01+ =uYuYuYn (E6) 4. Kmat JR(c) ( )21 =c EJKRmat(E7) 2 t R Ro m == 343.7 . n (E5) (E6) 1.657 7.325 ref - Ramberg-Osgood + =nYrefYrefY ref (E8) Lr ( ) ( )nr r Y r refL L L + = (E9) (E9) (24) ( )( )>+++=maxmax2 13; 0;2r rr r nr rrrnr rr rL LL LL LLLL LL K(E10) maxrL (23) ( ) ( ) = + 3 . 230 2 4 . 545 3 . 2301.68 ( )( )( ) c Kc M Kc Kmatr=,max(E11) ( )( ) c MMc LLrmax= (E12) Mmax (E11) (E12) 468 c ( 100 .) Mmax (E1), (E2), (E4) (E7) ( ) ( ) c FRcRt RMc M Kmmm + = 2maxmax, (E13) ( ) ++ ++ =24 . 4 5 . 16422 . 2 5967 . 4 1m mR c R cA c F (E14) ( )( ) + +=2sin2cos 42 m mY m LR c R ct R c M (E15) ( )( ) [ ]21 += mcmatc C J Ec K (E16) Mmax (600, 700 809 kN-m) E1E2Mmax=809kN-m 809 kN-m E1 Mmax = 600 kN-mMmax = 700 kN-mMmax = 809 kN-mc (.)KrLrKrLrKrLr 00.8810.6201.0280.7231.1890.836 50.5700.6310.6650.7370.7690.851 100.5430.6430.6330.7500.7320.867 150.5300.6550.6180.7650.7140.884 200.5230.6680.6100.7790.7050.900 250.5190.6810.6060.7940.7000.918 300.5180.6940.6040.8100.6980.936 350.5180.7080.6040.8260.6980.954 400.5190.7220.6060.8420.7000.973 450.5210.7360.6080.8590.7020.993 500.5230.7520.6110.8770.7061.013 550.2821.1580.2491.0230.711.034 600.2831.1820.2501.0440.7151.056 469m kN M = 600maxm kN 700m kN 8090 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.60.20.40.60.81.0LrKr (E10)1.2 E2 1. 1205.7 kN-m R6 2. 171-12(base metal)13-17(weldmetal)E2 17 E3 1 12 E4 13-17 3.13-17[(E10)] ( ) 4. E5 470 E2 2Ro (.)t (.) () 1API5L X65106715.90.372SA333 Gr6273.118.30.346 3STS-49763.5238.180.166 4A15571122.70.0625 5STS-41016614.50.166 6A106168140.36 7SA358 TP30410677.110.37 8SA312 TP30460.360.229 9SA376 TP304114.390.371 10SA358 TP30441426.20.368 11SA376 TP304158.913.90.388 12TP316L106.28.30.244 13SA106 Gr B168.311.050.304 14SA333 Gr 661231.30.079 15SA376 TP304168.314.30.371 16SA358 TP304413.526.20.367 17SA240 TP31671130.20.0625 E3 E (GPa) Y

(MPa) u

(MPa) Jc

(kN/m2) Cm 1API5L X65207.6425567 399528.30.49 2SA333 Gr6190.5239526158180.90.33 3STS-49190.1242583366248.10.55 4A155190.8231541.9206.5194.30.30 5STS-410190.1215.8492.6367.9249.80.58 6A106190.832062169111.40.33 7SA358 TP304206.8224681610354.40.39 8SA312 TP304205.92466575021037.30.54 9SA376 TP304205.92436291800333.20.39 10SA358 TP304205.929574420801019.30.75 11SA376 TP304190.81284471090248.70.09 12TP316L2062585276801014.70.62 471 E4 E (GPa) Y

(MPa) u (MPa) Jc

(kN/m2) Cm 190.8270610---13SA106 Gr B 190.8315669160200.60.42 190.8234521---14SA333 Gr 6 190.841557553103.20.48 190.8134451---15SA376 TP304 190.8325466100183.80.37 190.8174456---16SA358 TP304 190.8325466100183.80.37 190.8143427---17SA240 TP316 190.836650361200.30.53 E5 Mmax Mmax(kN-m) 1API5L X652668.62280 2SA333 Gr6154.84120 3STS-496015.43840 4A1553016.302550 5STS-41092.7666.5 6A10651.3338.5 7SA358 TP304915.6596 8SA312 TP3044.884.32 9SA376 TP30417.3513.8 10SA358 TP304784.55610 11SA376 TP30437.6621.6 12TP316L17.1116.6 13SA106 Gr B51.3638.2 14SA333 Gr 634162210 15SA376 TP30437.5021.4 16SA358 TP304377.14269 17SA240 TP3163063.622350 4727.7 [1] Assessmentoftheintegrityofstructurescontainingdefects.British Energy Generation report R6, Revision 3, 2000. [2] Methodofassessmentforflaws infusionweldedjointswithrespecttobrittlefractureandfatigue crack growth. WES 2805-1997, Japan Welding Engineering Society, Tokyo, 1997. [3] Fitness-for-service.API Recommended Practice 579,AmericanPetroleumInstitute,Washington, DC., 2000. [4] Anderson,T.L. Fracture Mechanics: Fundamental and Application, 2nd ed., CRC Press 1995. [5] Ainsworth,R.A.,Schwalbe,K.-H.,andZerbst,U.Crackdrivingforceestimationmethods. Comprehensive structural integrity Vol. 7, Practical failure assessment method.InR.A.Ainsworth and K.-H Schwalbe (eds.), 2003, pp. 142-148. [6] Ainsworth,R.A.Failureassessmentdiagrammethods.ComprehensivestructuralintegrityVol.7, Practical failure assessment method. In R.A. Ainsworth and K.-H Schwalbe (eds.), 2003, pp. 91-95.[7] Darlaston,B.J.L.ThedevelopmentandapplicationoftheCEGBtwocriteriaapproachforthe assessment of defects in structures. Advances in elasto-plastic fracture mechanics. In L.H.Larsson (ed.), 1979, p. 321. [8] Kumar,V.,German,M.D.,andShih,C.F.Anengineeringapproachforelastic-plasticfracture analysis EPRI NP-1931, 1981. [9] Milne, I., Dowling, A.R.Decide on margins and factors. Comprehensive structural integrity Vol. 7, Practical failure assessment method. In R.A. Ainsworth and K.-H Schwalbe (eds.), 2003, pp. 567-575. [10]Rao,B.N.,Acharya,A.R.FailureassessmentonM300grademaragingsteelcylindricalpressure vesselswithaninternalsurfacecrack.Int. J. of Pressure Vessels and Piping,Vol.75,1998,pp. 537-543. [11]Kim,Y.J.,Shim,D.J.,Huh,N.S.,andKim,Y.J.Elastic-Plasticfracturemechanicsassessmentof testdataforcircumferentialcrackedpipes.EngineeringFractureMechanics,Vol.71,2004,pp. 173-191. 473 WES 2805-1997 WES 2805:1997 ( 7.4) 1. a1.1 a a = (1) 1.2 2taF a = (2) )5 . 0 2 c a0F Ft =( ) ( ) [ ]gf t a M t a M M F4322 1 0+ + =( ) c a M 09 . 0 13 . 11 = c aM++ =2 . 089 . 054 . 02 ( ) [ ]2431 1465 . 015 . 0 c ac aM ++ =1 =gf( )65 . 1464 . 1 1 c a + = )0 . 1 2 5 . 0 < c a0F Ft =( ) ( ) [ ]gf t a M t a M M F4322 1 0+ + = 474( ) [ ] a c a c M 04 . 0 11+ =( )422 . 0 a c M=( )4311 . 0 a c M =( )( )235 . 0 1 . 1 t a a c fg+ =( )65 . 1464 . 1 1 a c + = 1.3 5 . 0 2 c a 2taF a = (3) 0F Ft = 2 1 0M M F = ( )( )( )4 3 23 3 22 3 21565 . 1 931 . 2 594 . 1 7965 . 0557 . 2 892 . 4 446 . 2 4698 . 09213 . 0 037 . 2 399 . 1 3826 . 0 ln + ++ + + + = M ( )( )( )4 3 23 3 22 3 22428 . 1 681 . 2 424 . 1 1327 . 0770 . 2 270 . 4 233 . 2 1631 . 09348 . 0 920 . 1 251 . 1 2597 . 0 ln + ++ + + + = M c a = +=21;5 . 0;5 . 0M fore tcM fore tc( )65 . 1464 . 1 1 c a + = e 2. 2.1 2 t b b tH + ( )EHb t +=1(4) H 2.1.1-2.1.3 475 avg Eavg =1(4) 2.1.1 5 . 0 = H2.1.2 ) 5 . 0 2 c a 2 50 . 1 75 . 047 . 0 05 . 1 55 . 0 12 . 0 22 . 1 1 + + + =tacacatacaH)0 . 1 2 5 . 0 < c a 2 50 . 1 75 . 038 . 1 93 . 1 55 . 0 41 . 0 04 . 0 1 + + + =tacacataacH2.1.3 5 . 0 2 c a tateH + = 2 2.2 Y R =2 R 1 (butt weld) (fillet weld) 00.6 00.6 0.20.6 (postweldheattreatment) R 0.15 4762.3 ( )1 31 =K K Kt Kt 2 += t Y nett YtY t tKKA KK KK;1;1 ( )( )ttntKK KA=+11 2 YYn ;1390ln 12 . 0= MPa net=net 2 Kt 1.5 t p 15 . 0 1t p 15 . 0 > ( ) t h w+ + 3 1t p 5 . 0 ( ) t h w 2 3 1 + +t p 5 . 0 > 1 477 2 () Kt 1 1 3t p 1 . 0 2t p 1 . 0 > 3t h 2t h > 1.5t p 1 . 0 1 t p 1 . 0 > 1 1.5t p 1 . 0 1 t p 1 . 0 > 1) p 2) p 3) p 479 1 1. 2.1 (prestress)() (1.1) 2.1 P a 2.2 600 0.92 . 400 1.50 . 2.3 60m MPa 2.1) DbaAPPDbaAPP 1.1 1Valiente, A., and Elices, M.Premature failure of prestressed steel bars.Eng. Fail. Ana., Vol. 5, 1998, pp. 219-227. 480 =DaM KD DPc4

13 2 5 . 0463 . 13 4445 . 2 6386 . 0 0806 . 1+ + = DaDaDaDaDaM D 36 . Kc 33m MPa3./ damagetolerantdesign fail safe 2 1. 2 120.t8 .2a=60. P20 2.120 -20 P K 1 2 K 1 2 a/R = 0.5 25 ( ) 388 . 1 10 404 . 1 10 748 . 12 2 3+ = RtP aKI ( ) 1 2 310 386 . 1 10 038 . 2 + =RtP aKII 2.1 2Ayatollahi, M.R., and Aliha, M.R.M.Wide range data for crack tip parameters in two disc-type specimens under mixed-mode loading. Computational material science, 2006, pp. 1-11. 2aPP2R 4812. B2h2a P2.2 K h