FORMATION ITech Code_Aster et Salomé- Méca module 4 : Génie Civil (ARN3960) - PDF

Description
FORMATION ITech Code_Aster et Salomé- Méca module 4 : Génie Civil (ARN3960) Recherche & Développement 2-3 mai 2016 Copyright EDF 2016 S. Michel-Ponnelle Part 2 Modeling of the prestressed reinforced concrete

Please download to get full document.

View again

of 41
All materials on our website are shared by users. If you have any questions about copyright issues, please report us to resolve them. We are always happy to assist you.
Information
Category:

Services

Publish on:

Views: 24 | Pages: 41

Extension: PDF | Download: 0

Share
Transcript
FORMATION ITech Code_Aster et Salomé- Méca module 4 : Génie Civil (ARN3960) Recherche & Développement 2-3 mai 2016 Copyright EDF 2016 S. Michel-Ponnelle Part 2 Modeling of the prestressed reinforced concrete Aster Génie Civil 02/05/2016 2 OUTLINE 1. MODELING OF THE REINFORCED CONCRETE IN A 3D MODEL IN A 2D MODEL IN A 1D MODEL WITH A GLOBAL MODEL 2. MODELING OF THE TENDONS Aster Génie Civil 02/05/2016 3 OUTLINE 1. MODELING OF THE REINFORCED CONCRETE IN A 3D MODEL IN A 2D MODEL IN A 1D MODEL WITH A GLOBAL MODEL 2. MODELING OF THE TENDONS Aster Génie Civil 02/05/2016 4 MODELING THE STEEL IN REINFORCED CONCRETE : IN A 3D MODEL Option #1 : use the BARRE model (or if needed POU_D_T) Mesh steels with SEG2 elements Behavior is 1D Steel and concrete nodes must be identical Perfect bond between steel and concrete Aster Génie Civil 02/05/2016 5 MODELING THE STEEL IN REINFORCED CONCRETE : IN A 3D MODEL Option #2 : use the GRILLE_MEMBRANE model Steel is meshed with 2D elements : QUAD4, TRIA3, QUAD8, TRIA6 Steel and concrete nodes must be identical Perfect bond between steel and concrete Behavior law 1D (GRILLE_ISOT_LINE,...) Overlay meshes for different directions of reinforcement (CREA_MAILLAGE) CREA_MAILLAGE( MODELE=MO, CREA_MAILLE=(_F(NOM = 'barreh', GROUP_MA = 'surf', PREF_MAILLE='h'), _F(NOM = 'barrev',group_ma = 'surf', PREF_MAILLE= V')) Aster Génie Civil 02/05/2016 6 MODELING THE STEEL IN REINFORCED CONCRETE : IN A 3D MODEL Option #3 : use the MEMBRANE model Steel is meshed with 2D elements : QUAD4, TRIA3, QUAD8, TRIA6 Steel and concrete nodes must be identical Perfect bond between steel and concrete Orthotropic behavior law : ELAS only Aster Génie Civil 02/05/2016 7 MODELING THE STEEL IN REINFORCED CONCRETE : IN A 3D MODEL Option #4 : use the 3D model Steel is meshed with 3D elements Perfect bond between steel and concrete if nodes are identical. Behavior law : no restriction Aster Génie Civil 02/05/2016 8 MODELING THE STEEL IN REINFORCED CONCRETE : IN A 3D MODEL Modeling the decohesion steel/concrete introduction of 3D_INTERFACE elements between concrete 3D and steel 3D or MEMBRANE the behavior law CZM_LAB_MIX CONCRETE REINFORCEMENT INTERFACE CONCRETE Aster Génie Civil 02/05/2016 9 MODELING THE STEEL IN REINFORCED CONCRETE : IN A 2D MODEL (PLAN OR AXIS) Option #1 : use the 2D_BARRE model Steel meshed with SEG2 elements Perfect bond between steel and concrete Behavior is 1D Option #2 : use the 2D model Steel is meshed with 2D elements Behavior law : no restriction Perfect bond between steel and concrete 2D/2D (decohesion by introducing X_JOINT elements with JOINT_BA law) Aster Génie Civil 02/05/ MODELING THE STEEL IN REINFORCED CONCRETE : WITH A SHELL MODEL (DKT) Use GRILLE_EXCENTREE Steel meshed with linear 2D elements : QUAD4 or TRIA3 Overlay meshes for different directions of reinforcement (CREA_MAILLAGE) Perfect bond between steel and concrete Behavior law 1D (GRILLE_ISOT_LINE,...) Acier H -1 Acier V-1 Acier H-2 Acier V_2 CONCRETE Aster Génie Civil 02/05/ MODELING THE STEEL IN REINFORCED CONCRETE : FOR A 1D MODEL Use of multi-fiber beam POU_D_EM/POU_D_TGM MESH 1D + Definition of the section of the beam : mesh/point by point (DEFI_GEOM_FIBRE) Aster Génie Civil 02/05/ SOME DETAILS FOR MEMBRANE, GRILLE_MEMBRANE, GRILLE_EXCENTREE MEMBRANE GRILLE_MEMBRANE GRILLE_EXCENTREE unknowns Displacement Displacement Displacement + rotation rigidity orthotropic 1D 1D Behavior law ELAS GRILLE_xxxx GRILLE_xxxx eccentricity No No yes Property DEFI_MATERIAU ELAS_MEMBRANE ELAS, ELAS, Property AFFE_CARA_ELEM MEMBRANE/ ANGL_REP or AXE GRILLE/ SECTION (m 2 /ml) ANGL_REP or AXE GRILLE/ SECTION (m 2 /ml), EXCENTREMENT, ANGL_REP or AXE COEF_RIGI_DRZ Be careful : for MEMBRANE elements, RHO: r [kg/m 3 ]* S[m 2 /ml] Aster Génie Civil 02/05/ SOME DETAILS FOR MEMBRANE, GRILLE_MEMBRANE, GRILLE_EXCENTREE Duplication of the mesh : V12.3 CREA_MAILLAGE( MODELE=MO, CREA_MAILLE=(_F(GROUP_MA = CONCRETE',name of the existing face NOM = AcierH1', name of the new group PREF_MAILLE= H1')) suffix used for the new mesh _F(GROUP_MA = CONCRETE', NOM = AcierV1', PREF_MAILLE= V1') ) Acier H1 Acier V1 Acier H2 Acier V2 CONCRETE Aster Génie Civil 02/05/ SOME DETAILS FOR MEMBRANE, GRILLE_MEMBRANE, GRILLE_EXCENTREE Definition of the local directions (X1,Y1,Z1) of the elements in AFFE_CARA_ELEM Option 1 : ANGL_REP= (a, b) to define X1 Option 2 : AXE= V (vx,vy,vz) to define Y1 For instance : If X1= X : (0,0) If X1= Y : (90,0) Aster Génie Civil 02/05/ SOME DETAILS FOR MEMBRANE, GRILLE_MEMBRANE, GRILLE_EXCENTREE Comparison on a flexural test (perfect adhesion of the bars) Excellent results with the membrane model Satisfactory results with the grid model Model Displacement Discrepancy ( dof) Reference model (3D) 87.1 µm Concrete only 119 µm 37 % Concrete + Grid model Concrete + Membrane model 84 µm 3.6 % 87.3 µm 0.2 % Aster Génie Civil 02/05/ MODELING THE REINFORCED CONCRETE : AN ALTERNATIVE USING GLOBAL MODEL OF REINFORCED CONCRETE DKTG elements and a global constitutive law GLRC_DM (moderate damage) DHRC (moderate damage+ cracking) GLRC_DAMA (damage for impact) More robust (no softening) especially for dynamic analysis Typical response in tension for GLRC_DM Aster Génie Civil 02/05/ OUTLINE Modeling of the reinforced concrete Modeling of the prestressed concrete Aster Génie Civil 02/05/ MODELING OF THE PRESTRESSED CONCRETE: PRINCIPLES Mesh of the tendon: With 3D elements With (GRILLE_)MEMBRANE (2D) Tensioning of the tendon: PRE_EPSI Fictive thermal strain With 1D element More sophisticate tools available in Code_Aster! Aster Génie Civil 02/05/ MODELING OF THE PRESTRESSED CONCRETE: PRINCIPLES If tendons = 1D elements embedded in a 3D or DKT mesh, specific tools (DEFI_CABLE_BP/CALC_PRECONT) enable : - to use a steel mesh independent of the concrete mesh - to take into account the tension s losses in the tendon such as friction types of elements are available : BARRE for grouted tendons CABLE_GAINE for ungrouted tendons New Aster Génie Civil 02/05/ MODELING OF THE UNGROUTED TENDON / GROUTED TENDON : MAIN DIFFERENCES GROUTED MESH SEG2 SEG3 UNGROUTED MODELING BARRE CABLE_GAINE Behavior law ELAS, VMIS_ISOT_LINE, KIT_DDI : a law for the tendon + CABLE_GAINE_FROT Prestressing STAT_NON_LINE or CALC_PRECONT CALC_PRECONT only Tension Prescribed formula Obtained by the calculation Aster Génie Civil 02/05/ MODELING OF THE GROUTED TENDON : PRESCRIBED FORMULA FOR THE TENSION IN THE TENDONS Example : tension at any point of the cable as recommended by BPEL91 F (s)= F (s) {x flu F 0 + x ret F 0 + r ( j) ρ 1000[ F (s) S a f prg μ 0] F (s)} Taking into account the instantaneous losses by friction and anchor recoil F c (s)= F 0 exp ( f α ϕs) F c (s) F (s)= [F c (d )] 2 Aster Génie Civil 02/05/ MODELING OF THE GROUTED TENDON : PRESCRIBED FORMULA FOR THE TENSION IN THE TENDONS Example : tension at any point of the cable as recommended by BPEL91 F (s)= F (s) {x flu F 0 + x ret F 0 + r ( j) ρ 1000[ F (s) S a σ y μ 0] F (s)} Creep of concrete Shrinkage of concrete Relaxation of steel (ETCC BPEL) Taking account of losses depending on time Aster Génie Civil 02/05/ MODELING OF THE GROUTED TENDON : DATA SETTINGS MBETON=DEFI_MATERIAU(ELAS=_F(E= 30.E9,...), BPEL_BETON= _F( PERT_FLUA = 0, ETCC_BETON=_F() PERT_RETR = 0),); MCABLE=DEFI_MATERIAU(ELAS=_F(E=200.E9 ), BPEL_ACIER=_F( FROT_COURB =3.0E-3, FROT_LINE =1.5E-3, F_PRG =1.94E11, RELAX_1000 = 0, MU0_RELAX = 0),) ETCC_ACIER=_F( COEF_FROT PERT_LIGNE F_PRG RELAX_1000 F 0, Δ,r( j) S a in DEFI_CABLE_BP in AFFE_CARA_ELEM Aster Génie Civil 02/05/ MODELING OF THE GROUTED TENDON METHODOLGY The DEFI_CABLE_BP command creates loads corresponding to : The link (assumed perfect) between the cable and concrete : automatic definition of Lagrange multipliers The calculation of tension in the cables as recommended by BPEL/ETCC GRI N1 N2 N3 N4 N5 N6 GRF cable1 [U ] Aster Génie Civil 02/05/ MODELING OF THE GROUTED TENDON DEFI_CABLE_BP COMMAND cabl_pr = DEFI_CABLE_BP ( MODELE = modele, CHAM_MATER = chmat, CARA_ELEM = caelem, GROUP_MA_BETON = grmabe, GRI N1 N2 N3 cable1 Required for kinematic links N4 N5 N6 GRF Aster Génie Civil 02/05/ MODELING OF THE GROUTED TENDON DEFI_CABLE_BP COMMAND cabl_pr = DEFI_CABLE_BP ( GRI N1 N2 N3 MODELE = modele, CHAM_MATER = chmat, cable1 CARA_ELEM = caelem, GROUP_MA_BETON = grmabe, TENSION_INIT = f0, RECUL_ANCRAGE = delta, ADHERANT = OUI ( NON ) TYPE_RELAX = SANS / BPEL / ETCC_DIRECT / ETCC_REPRISE R_J/NBH_RELAX N4 N5 N6 GRF Characteristics of the tendon for the tension estimation Aster Génie Civil 02/05/ MODELING OF THE GROUTED TENDON DEFI_CABLE_BP COMMAND cabl_pr = DEFI_CABLE_BP ( GRI N1 N2 N3 MODELE = modele, CHAM_MATER = chmat, cable1 CARA_ELEM = caelem, GROUP_MA_BETON = grmabe, TENSION_INIT = f0, RECUL_ANCRAGE = delta, ADHERANT = OUI ( NON ) TYPE_RELAX = SANS / BPEL / ETCC_DIRECT / ETCC_REPRISE R_J/NBH_RELAX DEFI_CABLE = _F ( GROUP_MA = cable1, GROUP_NO_ANCRAGE = ( GRI, GRF ),) TYPE_ANCRAGE = ( ACTIF, PASSIF ), TENSION_CT N4 Definition of the cable(s) N5 N6 GRF Aster Génie Civil 02/05/ MODELING OF THE GROUTED TENDON DEFI_CABLE_BP COMMAND [U ] cabl_pr = DEFI_CABLE_BP ( GRI GRF N1 N2 N3 N4 N5 N6 MODELE = modele, CHAM_MATER = chmat, cable1 CARA_ELEM = caelem, GROUP_MA_BETON = grmabe, TENSION_INIT = f0, RECUL_ANCRAGE = delta, ADHERANT = OUI ( NON ) TYPE_RELAX = SANS / BPEL / ETCC_DIRECT / ETCC_REPRISE R_J/NBH_RELAX DEFI_CABLE = _F ( GROUP_MA = cable1, GROUP_NO_ANCRAGE = ( GRI, GRF ), TYPE_ANCRAGE = ( ACTIF, PASSIF ), TENSION_CT CONE = _F ( RAYON = rayon, LONGUEUR = long, Definition of the «diffusion cone» PRESENT = ('OUI','NON')) ] Aster Génie Civil 02/05/ MODELING OF THE GROUTED TENDON: POTENTIAL DIFFICULTIES Aster Génie Civil 02/05/ MODELING OF THE GROUTED TENDON: DIFFUSION CONE Possibility of introducing a diffusion cone [U ] Real situation Without modelling the shaft With modeling of the effect of shaft vanishing mesh size required management of redundant boundary conditions Aster Génie Civil 02/05/ MODELING OF THE GROUTED TENDON METHODOLGY T The AFFE_CHAR_MECA command defines the effective loads CAB1 = DEFI_CABLE_BP (...) CMCAB=AFFE_CHAR_MECA( MODELE=MO, RELA_CINE_BP=_F(CABLE_BP=CAB1, SIGM_BPEL= OUI' or 'NON', RELA_CINE='OUI' or 'NON')) Dependant on the strategy used Aster Génie Civil 02/05/ MODELING OF THE GROUTED TENDON : TWO STRATEGIES Strategy #1 Strategy #2 chcab=affe_char_meca(... RELA_CINE_BP=_F( CABLE_BP=cable, SIGM_BPEL= OUI', RELA_CINE='OUI')) chcab =AFFE_CHAR_MECA(... RELA_CINE_BP=_F( CABLE_BP=cable, SIGM_BPEL= NON', RELA_CINE='OUI',),); RES1 = STAT_NON_LINE(... EXCIT=(_F(CHARGE = CLIM,), _F(CHARGE = chcab)),...,) RES1 = CALC_PRECONT(... EXCIT=(_F(CHARGE =CLIM,),), CABLE_BP=cable,...,) Aster Génie Civil 02/05/ MODELING OF THE GROUTED TENDON : TWO STRATEGIES Tensions le long du câble 6,E+06 5,E+06 4,E+06 Strategy #2 : CALC_PRECONT Tension (N) 3,E+06 2,E+06 Strategy #1 : STAT_NON_LINE 1,E+06 0,E Elément BPEL DCBP sans correction DCBP après correction STAT_NON_LINE Loss of tension due to the instantaneous strain of the concrete No stages for the prestress loading Easier implementation CALC_PRECONT Final tension in cables = BPEL/ETCC Allows prestress loading stages A little more complex Aster Génie Civil 02/05/ MODELING OF THE GROUTED TENDON : CALC_PRECONT COMMAND statnl [evol_noli] = CALC_PRECONT( reuse = statnl, ETAT_INIT = _F( ) MODELE = mo, CHAM_MATER = chmat, CARA_ELEM = carac, COMP_INCR = _F() INCREMENT =_F( LIST_INST = litps, INST_FIN = instfin,), EXCIT =(_F( CHARGE = chi ), ), [U ] Boundary conditions, instant loads, kinematic links related to tendons already prestressed CABLE_BP = cabl_pr, The cables that will be prestressed between instini and instfin CABLE_BP_INACTIF = cabl_pr, Inactive tendons (no stiffness) + mot-clé facteur STAT_NON_LINE) Aster Génie Civil 02/05/ MODELING OF THE GROUTED TENDON : EXAMPLE CAB_BP=DEFI_CABLE_BP(...) CH_L=AFFE_CHAR_MECA(MODELE=MO, RELA_CINE_BP=_F(CABLE_BP=CAB_BP, SIGM_BPEL= NON', RELA_CINE='OUI',),); Define the cable Define the load : CH_L contains the kinematic links EVOL = CALC_PRECONT(CABLE_BP = CAB_BP, EXCIT = _F(CHARGE = CL), INCREMENT =_F(LIST_INST=L, INST_FIN = 1., ) EVOL = STAT_NON_LINE(reuse =EVOL, ETAT_INIT =_F(EVOL_NOLI= EVOL) EXCIT=(_F(CHARGE= CL), F(CHARGE=CH_L), Aster Génie Civil 02/05/ MODELING OF THE GROUTED TENDON : EXAMPLE CAB_BP=DEFI_CABLE_BP(...) CH_L=AFFE_CHAR_MECA(MODELE=MO, RELA_CINE_BP=_F(CABLE_BP=CAB_BPi, SIGM_BPEL= NON', RELA_CINE='OUI',),); EVOL = CALC_PRECONT(CABLE_BP = CAB_BP, EXCIT = _F(CHARGE = CL), INCREMENT =_F(LIST_INST=L, INST_FIN = 1., ) EVOL = STAT_NON_LINE(reuse =EVOL, ETAT_INIT =_F(EVOL_NOLI= EVOL) EXCIT=(_F(CHARGE= CL), F(CHARGE=CH_L),. Tensioning of cables defined in CAB_BP, from t= 0 to 1 Loads : only boundary conditions + instant loads Aster Génie Civil 02/05/ MODELING OF THE GROUTED TENDON : EXAMPLE CAB_BP=DEFI_CABLE_BP(...) CH_L=AFFE_CHAR_MECA(MODELE=MO, SIGM_BPEL= NON', RELA_CINE_BP=_F(CABLE_BP=CAB_BPi, RELA_CINE='OUI',),); EVOL = CALC_PRECONT(CABLE_BP = CAB_BP, EXCIT = _F(CHARGE = CL), INCREMENT =_F(LIST_INST=L, INST_FIN = 1., ) EVOL = STAT_NON_LINE(reuse =EVOL, ETAT_INIT =_F(EVOL_NOLI= EVOL) EXCIT=(_F(CHARGE= CL), F(CHARGE=CH_L),. Continuation of the calculation Load : boundary conditions + kinematic links related to the tendons + other loads Aster Génie Civil 02/05/ MODELING OF THE TENDON : TIPS Combine a maximum tendons in DEFI_CABLE_BP Option CONE : Pay attention to redundant connections (not factorable matrix) + size of elements If TYPE_ANCRAGE = ('PASSIF', 'PASSIF'), there is no tension in the cable! For strategy#1, in case of a continuation calculation (POURSUITE), define a new load without tension, otherwise the two tensions will be added In case of non-linear simulation, pay attention to the loss you want to take into account with DEFI_CABLE_BP For prestress loading stages, you can alternate STAT_NON_LINE and CALC_PRECONT, but pay attention to the loads to be taken into account! For more details, see documentation U (or practical sessions) Aster Génie Civil 02/05/ THANKS Aster Génie Civil 02/05/ End of presentation Is something missing or unclear in this document? Or feeling happy to have read such a clear tutorial? Please, we welcome any feedbacks about Code_Aster training materials. Do not hesitate to share with us your comments on the Code_Aster forum dedicated thread. Aster Génie Civil 02/05/
Related Search
We Need Your Support
Thank you for visiting our website and your interest in our free products and services. We are nonprofit website to share and download documents. To the running of this website, we need your help to support us.

Thanks to everyone for your continued support.

No, Thanks