* fichier : q8ri_bcn.dgibi ************************************************************************ * Section : Mecanique Elastique ************************************************************************ OPTI ECHO 1 ; ****************************************************************** * TEST Q8RI BCN * * Verification of element Q8RI (QUA8 with 2x2 Gauss points) * * Elastic analysis of a square subjected to biaxial extension * ****************************************************************** TITRE 'VERIFICATION OF ELEMENT Q8RI' ; OPTI DIME 2 ELEM QUA8 MODE PLAN DEFO ; GRAPH='N'; * *------------ Geometry definition -------------------------------- * pa = 0. 0. ; pb = 10. 0. ; pc = 10. 10. ; pd = 0. 10 ; lab = pa DROIT 10 pb ;lbc = pb DROIT 10 pc ; lcd = pc DROIT 10 pd ;lda = pd DROIT 10 pa ; mesh = DALLER lab lbc lcd lda ; * SI (NEG GRAPH 'N'); TRACE mesh ; FINSI ; * *------------ Model and material --------------------------------- * mod1 = MODE mesh MECANIQUE ELASTIQUE Q8RI ; mat1 = MATE mod1 YOUN 1.E7 NU 0 ; * *------------ Stiffness and boundary conditions ------------------ * rig1 = RIGI mod1 mat1 ; bc_lab = BLOQ UY lab ; bc_lbc = BLOQ UX lbc ; bc_lcd = BLOQ UY lcd ; bc_lda = BLOQ UX lda ; bc_tot = bc_lab ET bc_lbc ET bc_lcd ET bc_lda ; rigtot = rig1 ET bc_tot ; * *------------ Prescribed displacements: dilatation --------------- * di_lbc = DEPI bc_lbc 0.01 ; di_lcd = DEPI bc_lcd 0.01 ; ftot = di_lbc ET di_lcd ; * *------------ Linear system -------------------------------------- * desp = RESO rigtot ftot ; *================================================================= * Postprocess *================================================================= * * Deformed mesh * SI (NEG GRAPH 'N') ; def0 = DEFO mesh desp 0. BLAN ; def1 = DEFO mesh desp 10. ROUG ; TRACE (def0 ET def1) ; FINSI ; * * Stresses computed with SIGM * stress1 = SIGM mod1 mat1 desp 'LINE' ; * * Stresses computed with EPSI and ELAS * strain = EPSI mod1 desp 'LINE' ; stress2 = ELAS mod1 strain mat1 ; * * Gradient of displacements computed with GRAD * grad1 = GRAD mod1 desp ; * * Verifications ERRE 0 ; * 1) stress1 = stress2 * difstres = MAXI (stress1-stress2) ABS ; SI (difstres > 1.E-4) ; ERRE 5 ; FINSI ; * * 2) smxx = smyy = 1.e4 , smzz = smxy = 0 * smxxmin = MINI (EXCO stress1 SMXX) ; dxxmin = ABS (smxxmin-1.E4) ; smxxmax = MAXI (EXCO stress1 SMXX) ; dxxmax = ABS (smxxmax-1.E4) ; smyymin = MINI (EXCO stress1 SMYY) ; dyymin = ABS (smyymin-1.E4) ; smyymax = MAXI (EXCO stress1 SMYY) ; dyymax = ABS (smyymax-1.E4) ; smzzmin = MINI (EXCO stress1 SMZZ) ; dzzmin = ABS smzzmin ; smzzmax = MAXI (EXCO stress1 SMZZ) ; dzzmax = ABS smzzmax ; smxymin = MINI (EXCO stress1 SMXY) ; dxymin = ABS smxymin ; smxymax = MAXI (EXCO stress1 SMXY) ; dxymax = ABS smxymax ; dif = PROG dxxmin dxxmax dyymin dyymax dzzmin dzzmax dxymin dxymax ; SI ( (MAXI dif ABS)> 1.E-4) ; ERRE 5 ; FINSI ; FIN ;