应变花

=E1NME1NNNN2MWM-75-CRdRNNMMaRbR)(a•••ABCaRbRcRdR)(b•ABCD•••RabRcRdR)(c52RaRb52aRcRdRaRbR1ABRcRdR252bRa=Rb=Rc=Rb=RR1=Ra+Rb=2RR2=Rc+Rd=2RtABR1=Ra+Rb=KRa+b=KR[N+W+t+N-W+t]=2KRN+tds=1-2=N+t-t=NNN=E.N=Eds52cds=a-b+c-d=N+W+t-N-W+t+t-t=2WM12112122MnTE-76-2dsWεε=)(1211νσσε−=E)(1122νσσε−=E)(12121νεενσ+−=E)(11222νεενσ+−=EttKRKRKRRεεε==∆=2.2222tNtNKRKRKRRεεεεε+=−=∆=2)(2111nMnMABPqbRdRaRcR)(adsWWEEεεσ⋅=⋅=214553b1=-3=13131=-3pq13RaRbRcRd53a53cds=a-b+d-c=1-3+1-3=41431dsεεε=−=131154OABCOA1B1C1XεxYyxyααεxεyxyαεxεyxyεαα-77-D45D45τ1σ3σaRbRD45D45τ1σ3σcRdR)(b••••ABCDaRdRcRbR)(c53dsdsdsEEEενενεννεεντσσ)1(4)44(1)(1231231+=−−=+−==−=εxOABCOA1B1C55BB1OBOB1OBOBα1yOABC56OBOBα2OB-78-αεαψαεδεαα211coscos/)cos()(xxdxdxdldl≈−==ααεψαεψααcossin)sin(.11xxdldx≈−=1+y=dydydxx)1(ε+dxyxoABC1A1B1Cαxyγ54'1'2COABααεααεαεψαcossinsin/coscos2yyydydydldy−=−=−≈'2OBdydxdxxεxyA1AB1'BCO1d)1(dδ1αψα55αεααεδεα22sinsin/sin)(yydydydldl=≈=ydydyAB'2BC'1COxydx1d)1(dδ562αψxyOABC''3COAB57BB3’OBα3αγααγψαψαα2333sinsin/sin)sin(⋅=⋅⋅≈−=xyxydydydlBBεxεyτxyεαψαεα=εα1+εα2+εα3=εxcos2α+εysin2α+γxysinαcosα2A2B3αα58OBEDOBODOXα90+αα90+α3OBOD-79-'3B'CdyCCBBxy⋅==γ''3ααγααγαψαδεααcossinsin/cossin/)cos()(333⋅⋅=⋅⋅≈−==xyxydydydyBBdldlABCOxydx)(dlδxyγdl3αψαdy57αγαεεεεε2sin22cos22xyyxyxa+−++=αγααεααεψψψψαααα2321sincossincossinxyyx+−=++=αγαεε2sin2sin2xyyx+−=BA1BCDEO1DxyODψOBψα2παπγ−258BODB1OD158ODOBαγαεεααγαεεγα2cos2sin)()sin(cos2sin)(22xyyxxyyx+−−=−+−−=42Bα2B5500+905sin20cos202Bxyxy2221)2()2(2xyyxyxγεεεεεε+−±+=56xyxy1212152xyxy123α1α2α34560-80-αγαεεψ2sin2sin2xyyxOB+−=αγαεεαπγαπεεψ22cos2sin2)2(sin)2sin(2xyyxxyyxOD+−−=+++−=2)2(πψψγπα=−+−OBODOBODψψγα−=02cos2sin)(=+−−=αγαεεεxyyxadadyxxytgεεγα−=02yxbacD90εD45εD0εD455959axcyx=0ºy=90º2B45bxyxy57xyxy68197360A0º=7810-645º=α=8910-6-45º=c=-31106E=215GPa=0.28600=x2B45-45ababy=45º+-45º-0ºxy=45º--45ºxyxy5100xyxy6-81-22290045xyγεεε++=DDDDDD900452εεεγ−−=xyDDDDD90090045022εεεεεα−−−=tg29045245090021)()(222DDDDDDεεεεεεεε−+−±+=29045245090021)()()1(22)1(2)(DDDDDDεεεευυεεσσ−+−+±−+=EE222045xyyγεεε++=D222045xyyγεεε−+=−DDDDD454504545022−−−−−=εεεεεαtgLAAlD45D45−yxpznMyx1σαcRaRD45−D450R601111210101x0=25.45912MPa-82-24545245450454521)2()22(200−−−−+−−±+=εεεεεεεεεDDDD245020454545)()(222DDDDεεεεεε−+−±+=−−24502045454521)()()1(22)1(2)(DDDDεεεεννεεσσ−+−+±−+=−−EE22.19812010)3189732(10)3189(2660==×+−××+=−−αtg632110)3189()28.01(210215−×−−×=εε[]1222310)8978()7831()28.01(2102152−×−+−−−××±−=±=35.47.2101.1366.8