Issue 15

I. S

. Raju et alii, Fr

attura ed Integri

tà Strutturale, 1

5 (2011) 35-49

; DOI: 10.3221/I

GF-ESIS.15.05

ode G value orbit cold is tive.

e G II values d indicating

n the G I valu parison of G

Th ope ove

e individual m ning for on rly conserva

s were also e dominated b

xamined. Th y Mode II an

are larger tha that the com

es, suggestin T to G Ic in F

g that the de ig. 16(b) may

fect be

(a) Interface

defect at craze at varyin

crack Locatio g craze crack l

n +1 and defo ocations (defo

rmed configu rmation scaled

rations for int by 20x).

erface defects

G T . ace defect loca

(b

) Normalized ction of interf

ed G T

16 : Normaliz

as a fun

tion – On-orb

it cold.

Figure

Sub Th loc use tips En and 17( nor Eq cas righ cas

strate Defects e fracture me ations and th d in this pap are located try Peak Heati the location b) for the le malized by G . 4 and norm es -2→+1 an t tip becom e -2→+4), th

– Effect of D chanics resp en extending er to indicate at Locations ng . To study of the right ft tip and in Ic , and the g alized by G I d -2→+2), t es larger than e left tip nor

efect Length onse for sub the defect a that a subsu A and B, resp “very long” s defect tip is v Fig. 17(c) fo reen dashed c . For the in he left tip is s the normal malized G T e

strate defects long the jogg rface defect e ectively, as i ubstrate defe aried along r the right ti curves repres itial case (i.e table, but th ized G T sugg xceeds the n

is examined le (i.e., chan xists between llustrated in F cts for entry the joggle up p. The blue ent the resis ., case -2→0 e right tip is u esting a retu ormalized R a

by fixing th ging the defe Location A ig. 17(a). peak heating, to Location curves repre tance to the ), both defec nstable. Fo rn to a stabl nd hence th

e left tip of t ct size or len and Locatio the left defe +4. The frac sent the tota defect drivin t tips are sta r the case -2→ e region. Fo e left tip beco

he defect at gth). The no n B. The left ct tip is place ture respons l defect driv g force, or R ble. For lon +3, the nor r the “very l mes unstable

different acre tation ‘A→B and right de d at Location e is given in ing force, or , evaluated u ger defects malized R at ong” defect .

age ’ is fect -2, Fig. G T , sing (i.e., the (i.e.,

E F A

FECT OF V A

RIOUS V AR

THE D EFE

CT D RIVIN

G F ORCE

IABLES ON

g force, the G of these varia

this ssed

s menti applica qualitat

oned previou tion. Some o ively.

sly, there are f these variab

many variab les are ident

les that cont ified in Fig. 1

ribute to the 8, and the ef

defect drivin fect of each

T value, for bles is discu

46