def run_pm4sand_et(sl, csr, esig_v0=101.0e3, static_bias=0.0, n_lim=100, k0=0.5, strain_limit=0.03, strain_inc=5.0e-6, etype='implicit'): nu_init = k0 / (1 + k0) damp = 0.02 omega0 = 0.2 omega1 = 20.0 a1 = 2. * damp / (omega0 + omega1) a0 = a1 * omega0 * omega1 # Initialise OpenSees instance osi = o3.OpenSeesInstance(ndm=2, ndf=3, state=3) # Establish nodes h_ele = 1. bl_node = o3.node.Node(osi, 0, 0) br_node = o3.node.Node(osi, h_ele, 0) tr_node = o3.node.Node(osi, h_ele, h_ele) tl_node = o3.node.Node(osi, 0, h_ele) all_nodes = [bl_node, br_node, tr_node, tl_node] # Fix bottom node o3.Fix3DOF(osi, bl_node, o3.cc.FIXED, o3.cc.FIXED, o3.cc.FIXED) o3.Fix3DOF(osi, br_node, o3.cc.FIXED, o3.cc.FIXED, o3.cc.FIXED) o3.Fix3DOF(osi, tr_node, o3.cc.FREE, o3.cc.FREE, o3.cc.FIXED) o3.Fix3DOF(osi, tl_node, o3.cc.FREE, o3.cc.FREE, o3.cc.FIXED) # Set out-of-plane DOFs to be slaved o3.EqualDOF(osi, tr_node, tl_node, [o3.cc.X, o3.cc.Y]) # Define material pm4sand = o3.nd_material.PM4Sand(osi, sl.relative_density, sl.g0_mod, sl.h_po, sl.unit_sat_mass, 101.3, nu=nu_init) # Note water bulk modulus is irrelevant since constant volume test - so as soil skeleton contracts # the bulk modulus of the soil skeleton controls the change in effective stress water_bulk_mod = 2.2e6 ele = o3.element.SSPquadUP(osi, all_nodes, pm4sand, 1.0, water_bulk_mod, 1., sl.permeability, sl.permeability, sl.e_curr, alpha=1.0e-5, b1=0.0, b2=0.0) o3.constraints.Transformation(osi) o3.test_check.NormDispIncr(osi, tol=1.0e-6, max_iter=35, p_flag=0) o3.numberer.RCM(osi) omegas = np.array(o3.get_eigen(osi, n=1))**0.5 periods = 2 * np.pi / omegas periods = [0.001] if etype == 'implicit': o3.algorithm.Newton(osi) o3.system.FullGeneral(osi) o3.integrator.Newmark(osi, gamma=5. / 6, beta=4. / 9) dt = 0.01 else: o3.algorithm.Linear(osi, factor_once=True) o3.system.FullGeneral(osi) if etype == 'newmark_explicit': o3.integrator.NewmarkExplicit(osi, gamma=0.5) explicit_dt = periods[0] / np.pi / 8 elif etype == 'central_difference': o3.integrator.CentralDifference(osi) explicit_dt = periods[0] / np.pi / 16 # 0.5 is a factor of safety elif etype == 'hht_explicit': o3.integrator.HHTExplicit(osi, alpha=0.5) explicit_dt = periods[0] / np.pi / 8 elif etype == 'explicit_difference': o3.integrator.ExplicitDifference(osi) explicit_dt = periods[0] / np.pi / 4 else: raise ValueError(etype) print('explicit_dt: ', explicit_dt) dt = explicit_dt o3.analysis.Transient(osi) freqs = [0.5, 10] xi = 0.1 use_modal_damping = 0 if use_modal_damping: omega_1 = 2 * np.pi * freqs[0] omega_2 = 2 * np.pi * freqs[1] a0 = 2 * xi * omega_1 * omega_2 / (omega_1 + omega_2) a1 = 2 * xi / (omega_1 + omega_2) o3.rayleigh.Rayleigh(osi, a0, 0, a1, 0) else: o3.ModalDamping(osi, [xi]) o3.update_material_stage(osi, pm4sand, stage=0) # print('here1: ', o3.get_ele_response(osi, ele, 'stress'), esig_v0, csr) all_stresses_cache = o3.recorder.ElementToArrayCache(osi, ele, arg_vals=['stress']) all_strains_cache = o3.recorder.ElementToArrayCache(osi, ele, arg_vals=['strain']) nodes_cache = o3.recorder.NodesToArrayCache(osi, all_nodes, dofs=[1, 2, 3], res_type='disp') o3.recorder.NodesToFile(osi, 'node_disp.txt', all_nodes, dofs=[1, 2, 3], res_type='disp') # Add static vertical pressure and stress bias ttime = 30 time_series = o3.time_series.Path(osi, time=[0, ttime, 1e10], values=[0, 1, 1]) o3.pattern.Plain(osi, time_series) o3.Load(osi, tl_node, [0, -esig_v0 / 2, 0]) o3.Load(osi, tr_node, [0, -esig_v0 / 2, 0]) o3.analyze(osi, num_inc=int(ttime / dt) + 10, dt=dt) ts2 = o3.time_series.Path(osi, time=[ttime, 80000, 1e10], values=[1., 1., 1.], factor=1) o3.pattern.Plain(osi, ts2, fact=1.) y_vert = o3.get_node_disp(osi, tr_node, o3.cc.Y) o3.SP(osi, tl_node, dof=o3.cc.Y, dof_values=[y_vert]) o3.SP(osi, tr_node, dof=o3.cc.Y, dof_values=[y_vert]) # Close the drainage valves for node in all_nodes: o3.remove_sp(osi, node, dof=3) o3.analyze(osi, int(5 / dt), dt=dt) print('here3: ', o3.get_ele_response(osi, ele, 'stress'), esig_v0, csr) o3.update_material_stage(osi, pm4sand, stage=1) o3.set_parameter(osi, value=0, eles=[ele], args=['FirstCall', pm4sand.tag]) o3.analyze(osi, int(5 / dt), dt=dt) o3.set_parameter(osi, value=sl.poissons_ratio, eles=[ele], args=['poissonRatio', pm4sand.tag]) o3.extensions.to_py_file(osi) n_cyc = 0.0 target_strain = 1.1 * strain_limit target_disp = target_strain * h_ele limit_reached = 0 export = 1 while n_cyc < n_lim: print('n_cyc: ', n_cyc) h_disp = o3.get_node_disp(osi, tr_node, o3.cc.X) curr_time = o3.get_time(osi) steps = target_strain / strain_inc ts0 = o3.time_series.Path(osi, time=[curr_time, curr_time + steps, 1e10], values=[h_disp, target_disp, target_disp], factor=1) pat0 = o3.pattern.Plain(osi, ts0) o3.SP(osi, tr_node, dof=o3.cc.X, dof_values=[1.0]) curr_stress = o3.get_ele_response(osi, ele, 'stress')[2] if math.isnan(curr_stress): raise ValueError if export: o3.extensions.to_py_file(osi) export = 0 while curr_stress < (csr - static_bias) * esig_v0: o3.analyze(osi, int(0.1 / dt), dt=dt) curr_stress = o3.get_ele_response(osi, ele, 'stress')[2] h_disp = o3.get_node_disp(osi, tr_node, o3.cc.X) print(h_disp, target_disp) if h_disp >= target_disp: print('STRAIN LIMIT REACHED - on load') limit_reached = 1 break if limit_reached: break n_cyc += 0.25 print('load reversal, n_cyc: ', n_cyc) curr_time = o3.get_time(osi) o3.remove_load_pattern(osi, pat0) o3.remove(osi, ts0) o3.remove_sp(osi, tr_node, dof=o3.cc.X) # Reverse cycle steps = (h_disp + target_disp) / (strain_inc * h_ele) ts0 = o3.time_series.Path(osi, time=[curr_time, curr_time + steps, 1e10], values=[h_disp, -target_disp, -target_disp], factor=1) pat0 = o3.pattern.Plain(osi, ts0) o3.SP(osi, tr_node, dof=o3.cc.X, dof_values=[1.0]) i = 0 while curr_stress > -(csr + static_bias) * esig_v0: o3.analyze(osi, int(0.1 / dt), dt=dt) curr_stress = o3.get_ele_response(osi, ele, 'stress')[2] h_disp = o3.get_node_disp(osi, tr_node, o3.cc.X) if -h_disp >= target_disp: print('STRAIN LIMIT REACHED - on reverse') limit_reached = 1 break i += 1 if i > steps: break if limit_reached: break n_cyc += 0.5 print('reload, n_cyc: ', n_cyc) curr_time = o3.get_time(osi) o3.remove_load_pattern(osi, pat0) o3.remove(osi, ts0) o3.remove_sp(osi, tr_node, dof=o3.cc.X) # reload cycle steps = (-h_disp + target_disp) / (strain_inc * h_ele) ts0 = o3.time_series.Path(osi, time=[curr_time, curr_time + steps, 1e10], values=[h_disp, target_disp, target_disp], factor=1) pat0 = o3.pattern.Plain(osi, ts0) o3.SP(osi, tr_node, dof=o3.cc.X, dof_values=[1.0]) while curr_stress < static_bias * esig_v0: o3.analyze(osi, int(0.1 / dt), dt=dt) curr_stress = o3.get_ele_response(osi, ele, 'stress')[2] h_disp = o3.get_node_disp(osi, tr_node, o3.cc.X) if h_disp >= target_disp: print('STRAIN LIMIT REACHED - on reload') limit_reached = 1 break if limit_reached: break o3.remove_load_pattern(osi, pat0) o3.remove(osi, ts0) o3.remove_sp(osi, tr_node, dof=o3.cc.X) n_cyc += 0.25 o3.wipe(osi) all_stresses = all_stresses_cache.collect() all_strains = all_strains_cache.collect() disps = nodes_cache.collect() stress = all_stresses[:, 2] strain = all_strains[:, 2] ppt = all_stresses[:, 1] return stress, strain, ppt, disps pass
def site_response(sp, asig, freqs=(0.5, 10), xi=0.03, analysis_dt=0.001, dy=0.5, analysis_time=None, outs=None, rec_dt=None, use_explicit=0): """ Run seismic analysis of a soil profile that has a compliant base Parameters ---------- sp: sfsimodels.SoilProfile object A soil profile asig: eqsig.AccSignal object An acceleration signal Returns ------- """ if analysis_time is None: analysis_time = asig.time[-1] if outs is None: outs = { 'ACCX': [0] } # Export the horizontal acceleration at the surface if rec_dt is None: rec_dt = analysis_dt osi = o3.OpenSeesInstance(ndm=2, ndf=2, state=3) assert isinstance(sp, sm.SoilProfile) sp.gen_split(props=['shear_vel', 'unit_mass'], target=dy) thicknesses = sp.split["thickness"] n_node_rows = len(thicknesses) + 1 node_depths = np.cumsum(sp.split["thickness"]) node_depths = np.insert(node_depths, 0, 0) ele_depths = (node_depths[1:] + node_depths[:-1]) / 2 unit_masses = sp.split["unit_mass"] / 1e3 grav = 9.81 omega_1 = 2 * np.pi * freqs[0] omega_2 = 2 * np.pi * freqs[1] a0 = 2 * xi * omega_1 * omega_2 / (omega_1 + omega_2) a1 = 2 * xi / (omega_1 + omega_2) k0 = 0.5 pois = k0 / (1 + k0) newmark_gamma = 0.5 newmark_beta = 0.25 ele_width = min(thicknesses) # Define nodes and set boundary conditions for simple shear deformation # Start at top and build down? sn = [[o3.node.Node(osi, 0, 0), o3.node.Node(osi, ele_width, 0)]] for i in range(1, n_node_rows): # Establish left and right nodes sn.append([ o3.node.Node(osi, 0, -node_depths[i]), o3.node.Node(osi, ele_width, -node_depths[i]) ]) # set x and y dofs equal for left and right nodes o3.EqualDOF(osi, sn[i][0], sn[i][1], [o3.cc.X, o3.cc.Y]) # Fix base nodes o3.Fix2DOF(osi, sn[-1][0], o3.cc.FREE, o3.cc.FIXED) o3.Fix2DOF(osi, sn[-1][1], o3.cc.FREE, o3.cc.FIXED) # Define dashpot nodes dashpot_node_l = o3.node.Node(osi, 0, -node_depths[-1]) dashpot_node_2 = o3.node.Node(osi, 0, -node_depths[-1]) o3.Fix2DOF(osi, dashpot_node_l, o3.cc.FIXED, o3.cc.FIXED) o3.Fix2DOF(osi, dashpot_node_2, o3.cc.FREE, o3.cc.FIXED) # define equal DOF for dashpot and soil base nodes o3.EqualDOF(osi, sn[-1][0], sn[-1][1], [o3.cc.X]) o3.EqualDOF(osi, sn[-1][0], dashpot_node_2, [o3.cc.X]) # define materials ele_thick = 1.0 # m soil_mats = [] prev_args = [] prev_kwargs = {} prev_sl_type = None eles = [] for i in range(len(thicknesses)): y_depth = ele_depths[i] sl_id = sp.get_layer_index_by_depth(y_depth) sl = sp.layer(sl_id) app2mod = {} if y_depth > sp.gwl: umass = sl.unit_sat_mass / 1e3 else: umass = sl.unit_dry_mass / 1e3 # Define material sl_class = o3.nd_material.ElasticIsotropic sl.e_mod = 2 * sl.g_mod * (1 + sl.poissons_ratio) / 1e3 app2mod['rho'] = 'unit_moist_mass' overrides = {'nu': sl.poissons_ratio, 'unit_moist_mass': umass} args, kwargs = o3.extensions.get_o3_kwargs_from_obj( sl, sl_class, custom=app2mod, overrides=overrides) changed = 0 if sl.type != prev_sl_type or len(args) != len(prev_args) or len( kwargs) != len(prev_kwargs): changed = 1 else: for j, arg in enumerate(args): if not np.isclose(arg, prev_args[j]): changed = 1 for pm in kwargs: if pm not in prev_kwargs or not np.isclose( kwargs[pm], prev_kwargs[pm]): changed = 1 if changed: mat = sl_class(osi, *args, **kwargs) prev_sl_type = sl.type prev_args = copy.deepcopy(args) prev_kwargs = copy.deepcopy(kwargs) soil_mats.append(mat) # def element nodes = [sn[i + 1][0], sn[i + 1][1], sn[i][1], sn[i][0]] # anti-clockwise eles.append( o3.element.SSPquad(osi, nodes, mat, o3.cc.PLANE_STRAIN, ele_thick, 0.0, -grav)) # eles.append(o3.element.Quad(osi, nodes, mat=mat, otype=o3.cc.PLANE_STRAIN, thick=ele_thick, pressure=0.0, rho=unit_masses[i], b2=grav)) # define material and element for viscous dampers base_sl = sp.layer(sp.n_layers) c_base = ele_width * base_sl.unit_dry_mass / 1e3 * sp.get_shear_vel_at_depth( sp.height) dashpot_mat = o3.uniaxial_material.Viscous(osi, c_base, alpha=1.) o3.element.ZeroLength(osi, [dashpot_node_l, dashpot_node_2], mats=[dashpot_mat], dirs=[o3.cc.DOF2D_X]) # Static analysis o3.constraints.Transformation(osi) o3.test_check.NormDispIncr(osi, tol=1.0e-4, max_iter=30, p_flag=0) o3.algorithm.Newton(osi) o3.numberer.RCM(osi) o3.system.ProfileSPD(osi) o3.integrator.Newmark(osi, newmark_gamma, newmark_beta) o3.analysis.Transient(osi) o3.analyze(osi, 40, 1.) for i in range(len(soil_mats)): if isinstance(soil_mats[i], o3.nd_material.PM4Sand) or isinstance( soil_mats[i], o3.nd_material.PressureIndependMultiYield): o3.update_material_stage(osi, soil_mats[i], 1) o3.analyze(osi, 50, 0.5) # reset time and analysis o3.set_time(osi, 0.0) o3.wipe_analysis(osi) ods = {} for otype in outs: if otype == 'ACCX': ods['ACCX'] = [] if isinstance(outs['ACCX'], str) and outs['ACCX'] == 'all': ods['ACCX'] = o3.recorder.NodesToArrayCache(osi, nodes=sn[:][0], dofs=[o3.cc.X], res_type='accel', dt=rec_dt) else: for i in range(len(outs['ACCX'])): ind = np.argmin(abs(node_depths - outs['ACCX'][i])) ods['ACCX'].append( o3.recorder.NodeToArrayCache(osi, node=sn[ind][0], dofs=[o3.cc.X], res_type='accel', dt=rec_dt)) if otype == 'TAU': ods['TAU'] = [] if isinstance(outs['TAU'], str) and outs['TAU'] == 'all': ods['TAU'] = o3.recorder.ElementsToArrayCache( osi, eles=eles, arg_vals=['stress'], dt=rec_dt) else: for i in range(len(outs['TAU'])): ind = np.argmin(abs(ele_depths - outs['TAU'][i])) ods['TAU'].append( o3.recorder.ElementToArrayCache(osi, ele=eles[ind], arg_vals=['stress'], dt=rec_dt)) if otype == 'STRS': ods['STRS'] = [] if isinstance(outs['STRS'], str) and outs['STRS'] == 'all': ods['STRS'] = o3.recorder.ElementsToArrayCache( osi, eles=eles, arg_vals=['strain'], dt=rec_dt) else: for i in range(len(outs['STRS'])): ind = np.argmin(abs(ele_depths - outs['STRS'][i])) ods['STRS'].append( o3.recorder.ElementToArrayCache(osi, ele=eles[ind], arg_vals=['strain'], dt=rec_dt)) # Define the dynamic analysis ts_obj = o3.time_series.Path(osi, dt=asig.dt, values=asig.velocity * 1, factor=c_base) o3.pattern.Plain(osi, ts_obj) o3.Load(osi, sn[-1][0], [1., 0.]) # Run the dynamic analysis if use_explicit: o3.system.FullGeneral(osi) # o3.algorithm.Newton(osi) o3.algorithm.Linear(osi) # o3.integrator.ExplicitDifference(osi) # o3.integrator.CentralDifference(osi) o3.integrator.NewmarkExplicit(osi, newmark_gamma) # also works else: o3.system.SparseGeneral(osi) o3.algorithm.Newton(osi) o3.integrator.Newmark(osi, newmark_gamma, newmark_beta) o3.numberer.RCM(osi) o3.constraints.Transformation(osi) n = 2 modal_damp = 0 omegas = np.array(o3.get_eigen(osi, n=n))**0.5 response_periods = 2 * np.pi / omegas print('response_periods: ', response_periods) if not modal_damp: o3.rayleigh.Rayleigh(osi, a0, a1, 0, 0) else: o3.ModalDamping(osi, [xi, xi]) o3.analysis.Transient(osi) o3.test_check.NormDispIncr(osi, tol=1.0e-6, max_iter=10) while o3.get_time(osi) < analysis_time: print(o3.get_time(osi)) if o3.analyze(osi, 1, analysis_dt): print('failed') break o3.wipe(osi) out_dict = {} for otype in ods: if isinstance(ods[otype], list): out_dict[otype] = [] for i in range(len(ods[otype])): out_dict[otype].append(ods[otype][i].collect()) out_dict[otype] = np.array(out_dict[otype]) else: out_dict[otype] = ods[otype].collect().T out_dict['time'] = np.arange(0, analysis_time, rec_dt) return out_dict
def site_response(sp, asig, freqs=(0.5, 10), xi=0.03, analysis_dt=0.001, dy=0.5, analysis_time=None, outs=None, rec_dt=None): """ Run seismic analysis of a soil profile - example based on: http://opensees.berkeley.edu/wiki/index.php/Site_Response_Analysis_of_a_Layered_Soil_Column_(Total_Stress_Analysis) Parameters ---------- sp: sfsimodels.SoilProfile object A soil profile asig: eqsig.AccSignal object An acceleration signal Returns ------- """ if analysis_time is None: analysis_time = asig.time[-1] if outs is None: outs = { 'ACCX': [0] } # Export the horizontal acceleration at the surface if rec_dt is None: rec_dt = analysis_dt osi = o3.OpenSeesInstance(ndm=2, ndf=2, state=3) assert isinstance(sp, sm.SoilProfile) sp.gen_split(props=['shear_vel', 'unit_mass'], target=dy) thicknesses = sp.split["thickness"] n_node_rows = len(thicknesses) + 1 node_depths = np.cumsum(sp.split["thickness"]) node_depths = np.insert(node_depths, 0, 0) ele_depths = (node_depths[1:] + node_depths[:-1]) / 2 unit_masses = sp.split["unit_mass"] / 1e3 grav = 9.81 omega_1 = 2 * np.pi * freqs[0] omega_2 = 2 * np.pi * freqs[1] a0 = 2 * xi * omega_1 * omega_2 / (omega_1 + omega_2) a1 = 2 * xi / (omega_1 + omega_2) k0 = 0.5 pois = k0 / (1 + k0) newmark_gamma = 0.5 newmark_beta = 0.25 ele_width = min(thicknesses) total_soil_nodes = len(thicknesses) * 2 + 2 # Define nodes and set boundary conditions for simple shear deformation # Start at top and build down? sn = [[o3.node.Node(osi, 0, 0), o3.node.Node(osi, ele_width, 0)]] for i in range(1, n_node_rows): # Establish left and right nodes sn.append([ o3.node.Node(osi, 0, -node_depths[i]), o3.node.Node(osi, ele_width, -node_depths[i]) ]) # set x and y dofs equal for left and right nodes o3.EqualDOF(osi, sn[i][0], sn[i][1], [o3.cc.X, o3.cc.Y]) sn = np.array(sn) # Fix base nodes o3.Fix2DOF(osi, sn[-1][0], o3.cc.FREE, o3.cc.FIXED) o3.Fix2DOF(osi, sn[-1][1], o3.cc.FREE, o3.cc.FIXED) # Define dashpot nodes dashpot_node_l = o3.node.Node(osi, 0, -node_depths[-1]) dashpot_node_2 = o3.node.Node(osi, 0, -node_depths[-1]) o3.Fix2DOF(osi, dashpot_node_l, o3.cc.FIXED, o3.cc.FIXED) o3.Fix2DOF(osi, dashpot_node_2, o3.cc.FREE, o3.cc.FIXED) # define equal DOF for dashpot and soil base nodes o3.EqualDOF(osi, sn[-1][0], sn[-1][1], [o3.cc.X]) o3.EqualDOF(osi, sn[-1][0], dashpot_node_2, [o3.cc.X]) # define materials ele_thick = 1.0 # m soil_mats = [] strains = np.logspace(-6, -0.5, 16) ref_strain = 0.005 rats = 1. / (1 + (strains / ref_strain)**0.91) prev_args = [] prev_kwargs = {} prev_sl_type = None eles = [] tau_inds = [] total_stress_inds = 0 strs_inds = [] total_strain_inds = 0 for i in range(len(thicknesses)): y_depth = ele_depths[i] sl_id = sp.get_layer_index_by_depth(y_depth) sl = sp.layer(sl_id) app2mod = {} if y_depth > sp.gwl: umass = sl.unit_sat_mass / 1e3 else: umass = sl.unit_dry_mass / 1e3 # Define material if sl.type == 'pm4sand': sl_class = o3.nd_material.PM4Sand overrides = {'nu': pois, 'p_atm': 101, 'unit_moist_mass': umass} app2mod = sl.app2mod elif sl.type == 'sdmodel': sl_class = o3.nd_material.StressDensity overrides = {'nu': pois, 'p_atm': 101, 'unit_moist_mass': umass} app2mod = sl.app2mod elif sl.type == 'pimy': sl_class = o3.nd_material.PressureIndependMultiYield overrides = { 'nu': pois, 'p_atm': 101, 'rho': umass, 'nd': 2.0, 'g_mod_ref': sl.g_mod / 1e3, 'bulk_mod_ref': sl.bulk_mod / 1e3, 'cohesion': sl.cohesion / 1e3, 'd': 0.0, # 'no_yield_surf': 20 } tau_inds.append(total_stress_inds + 3) # 4th total_stress_inds += 5 strs_inds.append(total_strain_inds + 2) # 3rd total_strain_inds += 3 else: sl_class = o3.nd_material.ElasticIsotropic sl.e_mod = 2 * sl.g_mod * (1 - sl.poissons_ratio) / 1e3 app2mod['rho'] = 'unit_moist_mass' overrides = {'nu': sl.poissons_ratio, 'unit_moist_mass': umass} # opw.extensions.to_py_file(osi) args, kwargs = o3.extensions.get_o3_kwargs_from_obj( sl, sl_class, custom=app2mod, overrides=overrides) changed = 0 if sl.type != prev_sl_type or len(args) != len(prev_args) or len( kwargs) != len(prev_kwargs): changed = 1 else: for j, arg in enumerate(args): if not np.isclose(arg, prev_args[j]): changed = 1 for pm in kwargs: if pm not in prev_kwargs or not np.isclose( kwargs[pm], prev_kwargs[pm]): changed = 1 if changed: mat = sl_class(osi, *args, **kwargs) prev_sl_type = sl.type prev_args = copy.deepcopy(args) prev_kwargs = copy.deepcopy(kwargs) soil_mats.append(mat) # def element nodes = [sn[i + 1][0], sn[i + 1][1], sn[i][1], sn[i][0]] # anti-clockwise # ele = o3.element.Quad(osi, nodes, ele_thick, o3.cc.PLANE_STRAIN, mat, b2=grav * unit_masses[i]) ele = o3.element.SSPquad(osi, nodes, mat, 'PlaneStrain', ele_thick, 0.0, b2=grav * unit_masses[i]) eles.append(ele) # define material and element for viscous dampers base_sl = sp.layer(sp.n_layers) c_base = ele_width * base_sl.unit_dry_mass / 1e3 * sp.get_shear_vel_at_depth( sp.height) dashpot_mat = o3.uniaxial_material.Viscous(osi, c_base, alpha=1.) o3.element.ZeroLength(osi, [dashpot_node_l, dashpot_node_2], mats=[dashpot_mat], dirs=[o3.cc.DOF2D_X]) # Static analysis o3.constraints.Transformation(osi) o3.test_check.NormDispIncr(osi, tol=1.0e-4, max_iter=30, p_flag=0) o3.algorithm.Newton(osi) o3.numberer.RCM(osi) o3.system.ProfileSPD(osi) o3.integrator.Newmark(osi, newmark_gamma, newmark_beta) o3.analysis.Transient(osi) o3.analyze(osi, 40, 1.) for i in range(len(soil_mats)): if isinstance(soil_mats[i], o3.nd_material.PM4Sand) or isinstance( soil_mats[i], o3.nd_material.PressureIndependMultiYield): o3.update_material_stage(osi, soil_mats[i], 1) o3.analyze(osi, 50, 0.5) # reset time and analysis o3.set_time(osi, 0.0) o3.wipe_analysis(osi) # o3.recorder.NodeToFile(osi, 'sample_out.txt', node=nd["R0L"], dofs=[o3.cc.X], res_type='accel') na = o3.recorder.NodeToArrayCache(osi, node=sn[0][0], dofs=[o3.cc.X], res_type='accel') otypes = ['ACCX', 'TAU', 'STRS'] ods = {} for otype in outs: if otype == 'ACCX': ods['ACCX'] = [] if isinstance(outs['ACCX'], str) and outs['ACCX'] == 'all': ods['ACCX'] = o3.recorder.NodesToArrayCache(osi, nodes=sn[:, 0], dofs=[o3.cc.X], res_type='accel', dt=rec_dt) else: for i in range(len(outs['ACCX'])): ind = np.argmin(abs(node_depths - outs['ACCX'][i])) ods['ACCX'].append( o3.recorder.NodeToArrayCache(osi, node=sn[ind][0], dofs=[o3.cc.X], res_type='accel', dt=rec_dt)) if otype == 'TAU': ods['TAU'] = [] if isinstance(outs['TAU'], str) and outs['TAU'] == 'all': ods['TAU'] = o3.recorder.ElementsToArrayCache( osi, eles=eles, arg_vals=['stress'], dt=rec_dt) else: for i in range(len(outs['TAU'])): ind = np.argmin(abs(ele_depths - outs['TAU'][i])) ods['TAU'].append( o3.recorder.ElementToArrayCache(osi, ele=eles[ind], arg_vals=['stress'], dt=rec_dt)) if otype == 'STRS': ods['STRS'] = [] if isinstance(outs['STRS'], str) and outs['STRS'] == 'all': ods['STRS'] = o3.recorder.ElementsToArrayCache( osi, eles=eles, arg_vals=['strain'], dt=rec_dt) else: for i in range(len(outs['STRS'])): ind = np.argmin(abs(ele_depths - outs['STRS'][i])) ods['STRS'].append( o3.recorder.ElementToArrayCache(osi, ele=eles[ind], arg_vals=['strain'], dt=rec_dt)) # Define the dynamic analysis ts_obj = o3.time_series.Path(osi, dt=asig.dt, values=asig.velocity * -1, factor=c_base) o3.pattern.Plain(osi, ts_obj) o3.Load(osi, sn[-1][0], [1., 0.]) # Run the dynamic analysis o3.algorithm.Newton(osi) o3.system.SparseGeneral(osi) o3.numberer.RCM(osi) o3.constraints.Transformation(osi) o3.integrator.Newmark(osi, newmark_gamma, newmark_beta) o3.rayleigh.Rayleigh(osi, a0, a1, 0, 0) o3.analysis.Transient(osi) o3.test_check.EnergyIncr(osi, tol=1.0e-7, max_iter=10) o3.extensions.to_py_file(osi) while opy.getTime() < analysis_time: print(opy.getTime()) if o3.analyze(osi, 1, analysis_dt): print('failed') break opy.wipe() out_dict = {} for otype in ods: if isinstance(ods[otype], list): out_dict[otype] = [] for i in range(len(ods[otype])): a = ods[otype][i].collect() out_dict[otype].append( a[3::4]) # TODO: not working for generic case out_dict[otype] = np.array(out_dict[otype]) else: if otype == 'TAU': a = ods[otype].collect() out_dict[otype] = a[:, tau_inds].T * 1e3 elif otype == 'STRS': a = ods[otype].collect() out_dict[otype] = a[:, strs_inds].T else: out_dict[otype] = ods[otype].collect().T out_dict['time'] = np.arange(0, len(out_dict[otype][0])) * rec_dt return out_dict
def update_to_nonlinear(self): from o3seespy import update_material_stage update_material_stage(self.osi, self, 1)
def run_ts_custom_strain(mat, esig_v0, strains, osi=None, nu_dyn=None, target_d_inc=0.00001, k0=None, etype='newmark_explicit', handle='silent', verbose=0, opyfile=None, dss=False, plain_strain=True, min_n=10, nl=True): # if dss: # raise ValueError('dss option is not working') damp = 0.05 omega0 = 0.2 omega1 = 20.0 a1 = 2. * damp / (omega0 + omega1) a0 = a1 * omega0 * omega1 if osi is None: osi = o3.OpenSeesInstance(ndm=2, ndf=2) mat.build(osi) # Establish nodes h_ele = 1. nodes = [ o3.node.Node(osi, 0.0, 0.0), o3.node.Node(osi, h_ele, 0.0), o3.node.Node(osi, h_ele, h_ele), o3.node.Node(osi, 0.0, h_ele) ] # Fix bottom node o3.Fix2DOF(osi, nodes[0], o3.cc.FIXED, o3.cc.FIXED) if k0 is None: o3.Fix2DOF(osi, nodes[1], o3.cc.FIXED, o3.cc.FIXED) # Set out-of-plane DOFs to be slaved o3.EqualDOF(osi, nodes[2], nodes[3], [o3.cc.X, o3.cc.Y]) else: # control k0 with node forces o3.Fix2DOF(osi, nodes[1], o3.cc.FIXED, o3.cc.FREE) if plain_strain: oop = 'PlaneStrain' else: oop = 'PlaneStress' ele = o3.element.SSPquad(osi, nodes, mat, oop, 1, 0.0, 0.0) angular_freqs = np.array(o3.get_eigen(osi, solver='fullGenLapack', n=2)) ** 0.5 print('angular_freqs: ', angular_freqs) periods = 2 * np.pi / angular_freqs xi = 0.03 o3.ModalDamping(osi, [xi, xi]) print('periods: ', periods) o3.constraints.Transformation(osi) o3.test_check.NormDispIncr(osi, tol=1.0e-6, max_iter=35, p_flag=0) o3.numberer.RCM(osi) if etype == 'implicit': o3.algorithm.Newton(osi) o3.system.FullGeneral(osi) o3.integrator.Newmark(osi, gamma=0.5, beta=0.25) dt = 0.01 else: o3.algorithm.Linear(osi, factor_once=True) o3.system.FullGeneral(osi) if etype == 'newmark_explicit': o3.integrator.NewmarkExplicit(osi, gamma=0.5) explicit_dt = periods[0] / np.pi / 8 elif etype == 'central_difference': o3.integrator.CentralDifference(osi) explicit_dt = periods[0] / np.pi / 16 # 0.5 is a factor of safety elif etype == 'hht_explicit': o3.integrator.HHTExplicit(osi, alpha=0.5) explicit_dt = periods[0] / np.pi / 8 elif etype == 'explicit_difference': o3.integrator.ExplicitDifference(osi) explicit_dt = periods[0] / np.pi / 4 else: raise ValueError(etype) print('explicit_dt: ', explicit_dt) dt = explicit_dt o3.analysis.Transient(osi) o3.update_material_stage(osi, mat, stage=0) # dt = 0.00001 tload = 60 n_steps = tload / dt # Add static vertical pressure and stress bias time_series = o3.time_series.Path(osi, time=[0, tload, 1e10], values=[0, 1, 1]) o3.pattern.Plain(osi, time_series) # ts0 = o3.time_series.Linear(osi, factor=1) # o3.pattern.Plain(osi, ts0) if k0: o3.Load(osi, nodes[2], [-esig_v0 / 2, -esig_v0 / 2]) o3.Load(osi, nodes[3], [esig_v0 / 2, -esig_v0 / 2]) o3.Load(osi, nodes[1], [-esig_v0 / 2, 0]) # node 0 is fixed else: o3.Load(osi, nodes[2], [0, -esig_v0 / 2]) o3.Load(osi, nodes[3], [0, -esig_v0 / 2]) print('Apply init stress to elastic element') o3.analyze(osi, num_inc=n_steps, dt=dt) stresses = o3.get_ele_response(osi, ele, 'stress') print('init_stress0: ', stresses) o3.load_constant(osi, tload) if hasattr(mat, 'update_to_nonlinear') and nl: print('set to nonlinear') mat.update_to_nonlinear() o3.analyze(osi, 10000, dt=dt) # if not nl: # mat.update_to_linear() if nu_dyn is not None: mat.set_nu(nu_dyn, eles=[ele]) o3.analyze(osi, 10000, dt=dt) # o3.extensions.to_py_file(osi) stresses = o3.get_ele_response(osi, ele, 'stress') print('init_stress1: ', stresses) # Prepare for reading results exit_code = None stresses = o3.get_ele_response(osi, ele, 'stress') if dss: o3.gen_reactions(osi) force0 = o3.get_node_reaction(osi, nodes[2], o3.cc.DOF2D_X) force1 = o3.get_node_reaction(osi, nodes[3], o3.cc.DOF2D_X) # force2 = o3.get_node_reaction(osi, nodes[0], o3.cc.DOF2D_X) stress = [force1 + force0] strain = [o3.get_node_disp(osi, nodes[2], dof=o3.cc.DOF2D_X)] sxy_ind = None gxy_ind = None # iforce0 = o3.get_node_reaction(osi, nodes[0], o3.cc.DOF2D_X) # iforce1 = o3.get_node_reaction(osi, nodes[1], o3.cc.DOF2D_X) # iforce2 = o3.get_node_reaction(osi, nodes[2], o3.cc.DOF2D_X) # iforce3 = o3.get_node_reaction(osi, nodes[3], o3.cc.DOF2D_X) # print(iforce0, iforce1, iforce2, iforce3, stresses[2]) else: ro = o3.recorder.load_recorder_options() import pandas as pd df = pd.read_csv(ro) mat_type = ele.mat.type dfe = df[(df['mat'] == mat_type) & (df['form'] == oop)] df_sxy = dfe[dfe['recorder'] == 'stress'] outs = df_sxy['outs'].iloc[0].split('-') sxy_ind = outs.index('sxy') df_gxy = dfe[dfe['recorder'] == 'strain'] outs = df_gxy['outs'].iloc[0].split('-') gxy_ind = outs.index('gxy') stress = [stresses[sxy_ind]] cur_strains = o3.get_ele_response(osi, ele, 'strain') strain = [cur_strains[gxy_ind]] time_series = o3.time_series.Path(osi, time=[0, tload, 1e10], values=[0, 1, 1]) o3.pattern.Plain(osi, time_series) disps = list(np.array(strains) * 1) d_per_dt = 0.01 diff_disps = np.diff(disps, prepend=0) time_incs = np.abs(diff_disps) / d_per_dt approx_n_steps = time_incs / dt time_incs = np.where(approx_n_steps < 800, 800 * dt, time_incs) approx_n_steps = time_incs / dt assert min(approx_n_steps) >= 8, approx_n_steps curr_time = o3.get_time(osi) times = list(np.cumsum(time_incs) + curr_time) disps.append(disps[-1]) times.append(1e10) disps = list(disps) n_steps_p2 = int((times[-2] - curr_time) / dt) + 10 print('n_steps: ', n_steps_p2) times.insert(0, curr_time) disps.insert(0, 0.0) init_disp = o3.get_node_disp(osi, nodes[2], dof=o3.cc.X) disps = list(np.array(disps) + init_disp) ts0 = o3.time_series.Path(osi, time=times, values=disps, factor=1) pat0 = o3.pattern.Plain(osi, ts0) o3.SP(osi, nodes[2], dof=o3.cc.X, dof_values=[1]) o3.SP(osi, nodes[3], dof=o3.cc.X, dof_values=[1]) print('init_disp: ', init_disp) print('path -times: ', times) print('path -values: ', disps) v_eff = [stresses[1]] h_eff = [stresses[0]] time = [o3.get_time(osi)] for i in range(int(n_steps_p2 / 200)): print(i / (n_steps_p2 / 200)) fail = o3.analyze(osi, 200, dt=dt) o3.gen_reactions(osi) stresses = o3.get_ele_response(osi, ele, 'stress') v_eff.append(stresses[1]) h_eff.append(stresses[0]) if dss: o3.gen_reactions(osi) force0 = o3.get_node_reaction(osi, nodes[2], o3.cc.DOF2D_X) force1 = o3.get_node_reaction(osi, nodes[3], o3.cc.DOF2D_X) stress.append(force1 + force0) strain.append(o3.get_node_disp(osi, nodes[2], dof=o3.cc.DOF2D_X)) else: stress.append(stresses[sxy_ind]) cur_strains = o3.get_ele_response(osi, ele, 'strain') strain.append(cur_strains[gxy_ind]) time.append(o3.get_time(osi)) if fail: break return np.array(stress), np.array(strain)-init_disp, np.array(v_eff), np.array(h_eff), np.array(time), exit_code
def run_2d_strain_driver_iso(osi, base_mat, esig_v0, disps, target_d_inc=0.00001, max_steps=10000, handle='silent', da_strain_max=0.05, max_cycles=200, srate=0.0001, esig_v_min=1.0, k0_init=1, verbose=0, cyc_lim_fail=True): if not np.isclose(k0_init, 1., rtol=0.05): raise ValueError(f'Only supports k0=1, current k0={k0_init:.3f}') max_steps_per_half_cycle = 50000 nodes = [ o3.node.Node(osi, 0.0, 0.0), o3.node.Node(osi, 1.0, 0.0), o3.node.Node(osi, 1.0, 1.0), o3.node.Node(osi, 0.0, 1.0) ] for node in nodes: o3.Fix2DOF(osi, node, 1, 1) mat = o3.nd_material.InitStressNDMaterial(osi, other=base_mat, init_stress=-esig_v0, n_dim=2) ele = o3.element.SSPquad(osi, nodes, mat, 'PlaneStrain', 1, 0.0, 0.0) # create analysis o3.constraints.Penalty(osi, 1.0e15, 1.0e15) o3.algorithm.Linear(osi) o3.numberer.RCM(osi) o3.system.FullGeneral(osi) o3.analysis.Static(osi) d_init = 0.0 d_max = 0.1 # element height is 1m max_time = (d_max - d_init) / srate ts0 = o3.time_series.Linear(osi, factor=1) o3.pattern.Plain(osi, ts0) o3.Load(osi, nodes[2], [1.0, 0.0]) o3.Load(osi, nodes[3], [1.0, 0.0]) o3.analyze(osi, 1) o3.set_parameter(osi, value=1, eles=[ele], args=['materialState']) o3.update_material_stage(osi, base_mat, 1) o3.analyze(osi, 1) exit_code = None # loop through the total number of cycles react = 0 strain = [0] stresses = o3.get_ele_response(osi, ele, 'stress') stress = [stresses[2]] v_eff = [stresses[1]] h_eff = [stresses[0]] d_incs = np.diff(disps, prepend=0) # orys = np.where(diffs >= 0, 1, -1) for i in range(len(disps)): d_inc_i = d_incs[i] if target_d_inc < abs(d_inc_i): n = int(abs(d_inc_i / target_d_inc)) d_step = d_inc_i / n else: n = 1 d_step = d_inc_i for j in range(n): o3.integrator.DisplacementControl(osi, nodes[2], o3.cc.DOF2D_X, -d_step) o3.Load(osi, nodes[2], [1.0, 0.0]) o3.Load(osi, nodes[3], [1.0, 0.0]) o3.analyze(osi, 1) o3.gen_reactions(osi) # react = o3.get_ele_response(osi, ele, 'force')[0] stresses = o3.get_ele_response(osi, ele, 'stress') v_eff.append(stresses[1]) h_eff.append(stresses[0]) force0 = o3.get_node_reaction(osi, nodes[0], o3.cc.DOF2D_X) force1 = o3.get_node_reaction(osi, nodes[1], o3.cc.DOF2D_X) stress.append(-force0 - force1) # stress.append(stresses[2]) end_strain = -o3.get_node_disp(osi, nodes[2], dof=o3.cc.DOF2D_X) strain.append(end_strain) return -np.array(stress), np.array(strain), np.array(v_eff), np.array(h_eff), exit_code
def run_2d_stress_driver(osi, base_mat, esig_v0, forces, d_step=0.001, max_steps=10000, handle='silent', da_strain_max=0.05, max_cycles=200, srate=0.0001, esig_v_min=1.0, k0_init=1, verbose=0, cyc_lim_fail=True): if k0_init != 1: raise ValueError('Only supports k0=1') max_steps_per_half_cycle = 50000 nodes = [ o3.node.Node(osi, 0.0, 0.0), o3.node.Node(osi, 1.0, 0.0), o3.node.Node(osi, 1.0, 1.0), o3.node.Node(osi, 0.0, 1.0) ] for node in nodes: o3.Fix2DOF(osi, node, 1, 1) mat = o3.nd_material.InitStressNDMaterial(osi, other=base_mat, init_stress=-esig_v0, n_dim=2) ele = o3.element.SSPquad(osi, nodes, mat, 'PlaneStrain', 1, 0.0, 0.0) # create analysis o3.constraints.Penalty(osi, 1.0e15, 1.0e15) o3.algorithm.Linear(osi) o3.numberer.RCM(osi) o3.system.FullGeneral(osi) o3.analysis.Static(osi) d_init = 0.0 d_max = 0.1 # element height is 1m max_time = (d_max - d_init) / srate ts0 = o3.time_series.Linear(osi, factor=1) o3.pattern.Plain(osi, ts0) o3.Load(osi, nodes[2], [1.0, 0.0]) o3.Load(osi, nodes[3], [1.0, 0.0]) o3.analyze(osi, 1) o3.set_parameter(osi, value=1, eles=[ele], args=['materialState']) o3.update_material_stage(osi, base_mat, 1) o3.analyze(osi, 1) exit_code = None print('hhh') # loop through the total number of cycles react = 0 strain = [0] stresses = o3.get_ele_response(osi, ele, 'stress') stress = [stresses[2]] v_eff = [stresses[1]] h_eff = [stresses[0]] diffs = np.diff(forces, prepend=0) orys = np.where(diffs >= 0, 1, -1) for i in range(len(forces)): print('i: ', i, d_step) ory = orys[i] o3.integrator.DisplacementControl(osi, nodes[2], o3.cc.DOF2D_X, -d_step * ory) o3.Load(osi, nodes[2], [ory * 1.0, 0.0]) o3.Load(osi, nodes[3], [ory * 1.0, 0.0]) for j in range(max_steps): if react * ory < forces[i] * ory: o3.analyze(osi, 1) else: print('reached!') break o3.gen_reactions(osi) # react = o3.get_ele_response(osi, ele, 'force')[0] stresses = o3.get_ele_response(osi, ele, 'stress') # print(stresses) tau = stresses[2] print(tau, forces[i], ory) react = -tau v_eff.append(stresses[1]) h_eff.append(stresses[0]) stress.append(tau) end_strain = -o3.get_node_disp(osi, nodes[2], dof=o3.cc.DOF2D_X) strain.append(end_strain) if j == max_steps - 1: if handle == 'silent': break if handle == 'warn': print(f'Target force not reached: force={react:.4g}, target: {forces[i]:.4g}') else: raise ValueError() return np.array(stress), np.array(strain), np.array(v_eff), np.array(h_eff), exit_code
def run_2d_strain_driver(osi, mat, esig_v0, disps, target_d_inc=0.00001, handle='silent', verbose=0): k0 = 1.0 pois = k0 / (1 + k0) damp = 0.05 omega0 = 0.2 omega1 = 20.0 a1 = 2. * damp / (omega0 + omega1) a0 = a1 * omega0 * omega1 # Establish nodes h_ele = 1. nodes = [ o3.node.Node(osi, 0.0, 0.0), o3.node.Node(osi, h_ele, 0.0), o3.node.Node(osi, h_ele, h_ele), o3.node.Node(osi, 0.0, h_ele) ] # Fix bottom node o3.Fix2DOF(osi, nodes[0], o3.cc.FIXED, o3.cc.FIXED) o3.Fix2DOF(osi, nodes[1], o3.cc.FIXED, o3.cc.FIXED) o3.Fix2DOF(osi, nodes[2], o3.cc.FREE, o3.cc.FREE) o3.Fix2DOF(osi, nodes[3], o3.cc.FREE, o3.cc.FREE) # Set out-of-plane DOFs to be slaved o3.EqualDOF(osi, nodes[2], nodes[3], [o3.cc.X, o3.cc.Y]) ele = o3.element.SSPquad(osi, nodes, mat, 'PlaneStrain', 1, 0.0, 0.0) o3.constraints.Transformation(osi) o3.test_check.NormDispIncr(osi, tol=1.0e-3, max_iter=35, p_flag=0) o3.algorithm.Newton(osi) o3.numberer.RCM(osi) o3.system.FullGeneral(osi) o3.integrator.DisplacementControl(osi, nodes[2], o3.cc.DOF2D_Y, 0.005) # o3.rayleigh.Rayleigh(osi, a0, a1, 0.0, 0.0) o3.analysis.Static(osi) o3.update_material_stage(osi, mat, stage=0) # Add static vertical pressure and stress bias # time_series = o3.time_series.Path(osi, time=[0, 100, 1e10], values=[0, 1, 1]) # o3.pattern.Plain(osi, time_series) ts0 = o3.time_series.Linear(osi, factor=1) o3.pattern.Plain(osi, ts0) o3.Load(osi, nodes[2], [0, -esig_v0 / 2]) o3.Load(osi, nodes[3], [0, -esig_v0 / 2]) o3.analyze(osi, num_inc=100) stresses = o3.get_ele_response(osi, ele, 'stress') print('init_stress0: ', stresses) # ts2 = o3.time_series.Path(osi, time=[110, 80000, 1e10], values=[1., 1., 1.], factor=1) # o3.pattern.Plain(osi, ts2, fact=1.) # y_vert = o3.get_node_disp(osi, nodes[2], o3.cc.Y) # o3.SP(osi, nodes[3], dof=o3.cc.Y, dof_values=[y_vert]) # o3.SP(osi, nodes[2], dof=o3.cc.Y, dof_values=[y_vert]) # # o3.analyze(osi, 25, dt=1) o3.wipe_analysis(osi) o3.constraints.Transformation(osi) o3.test_check.NormDispIncr(osi, tol=1.0e-6, max_iter=35, p_flag=0) o3.algorithm.Newton(osi) o3.numberer.RCM(osi) o3.system.FullGeneral(osi) o3.analysis.Static(osi) o3.update_material_stage(osi, mat, stage=1) o3.analyze(osi, 25, dt=1) # o3.set_parameter(osi, value=sl.poissons_ratio, eles=[ele], args=['poissonRatio', 1]) # o3.extensions.to_py_file(osi) stresses = o3.get_ele_response(osi, ele, 'stress') print('init_stress1: ', stresses) exit_code = None strain = [0] stresses = o3.get_ele_response(osi, ele, 'stress') force0 = o3.get_node_reaction(osi, nodes[0], o3.cc.DOF2D_X) force1 = o3.get_node_reaction(osi, nodes[1], o3.cc.DOF2D_X) stress = [-force0 - force1] v_eff = [stresses[1]] h_eff = [stresses[0]] d_incs = np.diff(disps, prepend=0) for i in range(len(disps)): d_inc_i = d_incs[i] if target_d_inc < abs(d_inc_i): n = int(abs(d_inc_i / target_d_inc)) d_step = d_inc_i / n else: n = 1 d_step = d_inc_i for j in range(n): o3.integrator.DisplacementControl(osi, nodes[2], o3.cc.DOF2D_X, -d_step) o3.Load(osi, nodes[2], [1.0, 0.0]) o3.Load(osi, nodes[3], [1.0, 0.0]) o3.analyze(osi, 1) o3.gen_reactions(osi) stresses = o3.get_ele_response(osi, ele, 'stress') print(stresses) v_eff.append(stresses[1]) h_eff.append(stresses[0]) force0 = o3.get_node_reaction(osi, nodes[0], o3.cc.DOF2D_X) force1 = o3.get_node_reaction(osi, nodes[1], o3.cc.DOF2D_X) stress.append(-force0 - force1) end_strain = o3.get_node_disp(osi, nodes[2], dof=o3.cc.DOF2D_X) strain.append(end_strain) return -np.array(stress), -np.array(strain), np.array(v_eff), np.array(h_eff), exit_code