def test_ele_load_uniform(): osi = o3.OpenSeesInstance(ndm=2, state=3) ele_len = 2.0 coords = [[0, 0], [ele_len, 0]] ele_nodes = [o3.node.Node(osi, *coords[x]) for x in range(len(coords))] transf = o3.geom_transf.Linear2D(osi, []) ele = o3.element.ElasticBeamColumn2D(osi, ele_nodes=ele_nodes, area=1.0, e_mod=1.0, iz=1.0, transf=transf, mass=1.0, c_mass="string") for i, node in enumerate(ele_nodes): if i == 0: o3.Fix3DOF(osi, node, o3.cc.FIXED, o3.cc.FIXED, o3.cc.FIXED) else: o3.Fix3DOF(osi, node, o3.cc.FREE, o3.cc.FIXED, o3.cc.FIXED) ts_po = o3.time_series.Linear(osi, factor=1) o3.pattern.Plain(osi, ts_po) udl = 10. o3.EleLoad2DUniform(osi, ele, w_y=-udl) tol = 1.0e-4 o3.constraints.Plain(osi) o3.numberer.RCM(osi) o3.system.BandGeneral(osi) o3.test_check.NormDispIncr(osi, tol, 6) o3.algorithm.Newton(osi) n_steps_gravity = 1 d_gravity = 1. / n_steps_gravity o3.integrator.LoadControl(osi, d_gravity, num_iter=10) o3.analysis.Static(osi) o3.analyze(osi, n_steps_gravity) opy.reactions() ele_loads = o3.get_ele_response(osi, ele, 'force') assert np.isclose(ele_loads[0], 0.0) assert np.isclose(ele_loads[1], udl * ele_len / 2) assert np.isclose(ele_loads[2], udl * ele_len**2 / 12) assert np.isclose(ele_loads[3], 0.0) assert np.isclose(ele_loads[4], udl * ele_len / 2) assert np.isclose(ele_loads[5], -udl * ele_len**2 / 12) assert np.isclose(o3.get_node_reaction(osi, ele_nodes[0], o3.cc.Y), udl * ele_len / 2)
def get_inelastic_response(fb, asig, extra_time=0.0, xi=0.05, analysis_dt=0.001): """ Run seismic analysis of a nonlinear FrameBuilding Parameters ---------- fb: sfsimodels.Frame2DBuilding object asig: eqsig.AccSignal object extra_time xi analysis_dt Returns ------- """ osi = o3.OpenSeesInstance(ndm=2) q_floor = 10000. # kPa trib_width = fb.floor_length trib_mass_per_length = q_floor * trib_width / 9.8 # Establish nodes and set mass based on trib area # Nodes named as: C<column-number>-S<storey-number>, first column starts at C1-S0 = ground level left nd = OrderedDict() col_xs = np.cumsum(fb.bay_lengths) col_xs = np.insert(col_xs, 0, 0) n_cols = len(col_xs) sto_ys = fb.heights sto_ys = np.insert(sto_ys, 0, 0) for cc in range(1, n_cols + 1): for ss in range(fb.n_storeys + 1): nd[f"C{cc}-S{ss}"] = o3.node.Node(osi, col_xs[cc - 1], sto_ys[ss]) if ss != 0: if cc == 1: node_mass = trib_mass_per_length * fb.bay_lengths[0] / 2 elif cc == n_cols: node_mass = trib_mass_per_length * fb.bay_lengths[-1] / 2 else: node_mass = trib_mass_per_length * (fb.bay_lengths[cc - 2] + fb.bay_lengths[cc - 1] / 2) o3.set_node_mass(osi, nd[f"C{cc}-S{ss}"], node_mass, 0., 0.) # Set all nodes on a storey to have the same displacement for ss in range(0, fb.n_storeys + 1): for cc in range(1, n_cols + 1): o3.set_equal_dof(osi, nd[f"C1-S{ss}"], nd[f"C{cc}-S{ss}"], o3.cc.X) # Fix all base nodes for cc in range(1, n_cols + 1): o3.Fix3DOF(osi, nd[f"C{cc}-S0"], o3.cc.FIXED, o3.cc.FIXED, o3.cc.FIXED) # Coordinate transformation transf = o3.geom_transf.Linear2D(osi, []) l_hinge = fb.bay_lengths[0] * 0.1 # Define material e_conc = 30.0e6 i_beams = 0.4 * fb.beam_widths * fb.beam_depths ** 3 / 12 i_columns = 0.5 * fb.column_widths * fb.column_depths ** 3 / 12 a_beams = fb.beam_widths * fb.beam_depths a_columns = fb.column_widths * fb.column_depths ei_beams = e_conc * i_beams ei_columns = e_conc * i_columns eps_yield = 300.0e6 / 200e9 phi_y_col = calc_yield_curvature(fb.column_depths, eps_yield) phi_y_beam = calc_yield_curvature(fb.beam_depths, eps_yield) * 10 # TODO: re-evaluate # Define beams and columns # Columns named as: C<column-number>-S<storey-number>, first column starts at C1-S0 = ground floor left # Beams named as: B<bay-number>-S<storey-number>, first beam starts at B1-S1 = first storey left (foundation at S0) md = OrderedDict() # material dict sd = OrderedDict() # section dict ed = OrderedDict() # element dict for ss in range(fb.n_storeys): # set columns for cc in range(1, fb.n_cols + 1): lp_i = 0.4 lp_j = 0.4 # plastic hinge length ele_str = f"C{cc}-S{ss}S{ss+1}" top_sect = o3.section.Elastic2D(osi, e_conc, a_columns[ss][cc - 1], i_columns[ss][cc - 1]) bot_sect = o3.section.Elastic2D(osi, e_conc, a_columns[ss][cc - 1], i_columns[ss][cc - 1]) centre_sect = o3.section.Elastic2D(osi, e_conc, a_columns[ss][cc - 1], i_columns[ss][cc - 1]) sd[ele_str + "T"] = top_sect sd[ele_str + "B"] = bot_sect sd[ele_str + "C"] = centre_sect integ = o3.beam_integration.HingeMidpoint(osi, bot_sect, lp_i, top_sect, lp_j, centre_sect) bot_node = nd[f"C{cc}-S{ss}"] top_node = nd[f"C{cc}-S{ss+1}"] ed[ele_str] = o3.element.ForceBeamColumn(osi, [bot_node, top_node], transf, integ) # Set beams for bb in range(1, fb.n_bays + 1): lp_i = 0.5 lp_j = 0.5 ele_str = f"C{bb-1}C{bb}-S{ss}" mat = o3.uniaxial_material.ElasticBilin(osi, ei_beams[ss][bb - 1], 0.05 * ei_beams[ss][bb - 1], phi_y_beam[ss][bb - 1]) md[ele_str] = mat left_sect = o3.section.Uniaxial(osi, mat, quantity=o3.cc.M_Z) right_sect = o3.section.Uniaxial(osi, mat, quantity=o3.cc.M_Z) centre_sect = o3.section.Elastic2D(osi, e_conc, a_beams[ss][bb - 1], i_beams[ss][bb - 1]) integ = o3.beam_integration.HingeMidpoint(osi, left_sect, lp_i, right_sect, lp_j, centre_sect) left_node = nd[f"C{bb}-S{ss+1}"] right_node = nd[f"C{bb+1}-S{ss+1}"] ed[ele_str] = o3.element.ForceBeamColumn(osi, [left_node, right_node], transf, integ) # Define the dynamic analysis a_series = o3.time_series.Path(osi, dt=asig.dt, values=-1 * asig.values) # should be negative o3.pattern.UniformExcitation(osi, dir=o3.cc.X, accel_series=a_series) # set damping based on first eigen mode angular_freq_sqrd = o3.get_eigen(osi, solver='fullGenLapack', n=1) if hasattr(angular_freq_sqrd, '__len__'): angular_freq = angular_freq_sqrd[0] ** 0.5 else: angular_freq = angular_freq_sqrd ** 0.5 if isinstance(angular_freq, complex): raise ValueError("Angular frequency is complex, issue with stiffness or mass") beta_k = 2 * xi / angular_freq o3.rayleigh.Rayleigh(osi, alpha_m=0.0, beta_k=beta_k, beta_k_init=0.0, beta_k_comm=0.0) # Run the dynamic analysis o3.wipe_analysis(osi) o3.algorithm.Newton(osi) o3.system.SparseGeneral(osi) o3.numberer.RCM(osi) o3.constraints.Transformation(osi) o3.integrator.Newmark(osi, 0.5, 0.25) o3.analysis.Transient(osi) tol = 1.0e-4 iter = 4 o3.test_check.EnergyIncr(osi, tol, iter, 0, 2) analysis_time = (len(asig.values) - 1) * asig.dt + extra_time outputs = { "time": [], "rel_disp": [], "rel_accel": [], "rel_vel": [], "force": [], "ele_mom": [], "ele_curve": [], } print("Analysis starting") while o3.get_time(osi) < analysis_time: curr_time = opy.getTime() o3.analyze(osi, 1, analysis_dt) outputs["time"].append(curr_time) outputs["rel_disp"].append(o3.get_node_disp(osi, nd["C%i-S%i" % (1, fb.n_storeys)], o3.cc.X)) outputs["rel_vel"].append(o3.get_node_vel(osi, nd["C%i-S%i" % (1, fb.n_storeys)], o3.cc.X)) outputs["rel_accel"].append(o3.get_node_accel(osi, nd["C%i-S%i" % (1, fb.n_storeys)], o3.cc.X)) # outputs['ele_mom'].append(opy.eleResponse('-ele', [ed['B%i-S%i' % (1, 0)], 'basicForce'])) o3.gen_reactions(osi) react = 0 for cc in range(1, fb.n_cols): react += -o3.get_node_reaction(osi, nd["C%i-S%i" % (cc, 0)], o3.cc.X) outputs["force"].append(react) # Should be negative since diff node o3.wipe(osi) for item in outputs: outputs[item] = np.array(outputs[item]) return outputs
def get_inelastic_response(mass, k_spring, f_yield, motion, dt, xi=0.05, r_post=0.0): """ Run seismic analysis of a nonlinear SDOF :param mass: SDOF mass :param k_spring: spring stiffness :param f_yield: yield strength :param motion: list, acceleration values :param dt: float, time step of acceleration values :param xi: damping ratio :param r_post: post-yield stiffness :return: """ osi = o3.OpenSeesInstance(ndm=2) # Establish nodes bot_node = o3.node.Node(osi, 0, 0) top_node = o3.node.Node(osi, 0, 0) # Fix bottom node o3.Fix3DOF(osi, top_node, o3.cc.FREE, o3.cc.FIXED, o3.cc.FIXED) o3.Fix3DOF(osi, bot_node, o3.cc.FIXED, o3.cc.FIXED, o3.cc.FIXED) # Set out-of-plane DOFs to be slaved o3.EqualDOF(osi, top_node, bot_node, [o3.cc.Y, o3.cc.DOF2D_ROTZ]) # nodal mass (weight / g): o3.Mass(osi, top_node, mass, 0., 0.) # Define material bilinear_mat = o3.uniaxial_material.Steel01(osi, fy=f_yield, e0=k_spring, b=r_post) # Assign zero length element, # Note: pass actual node and material objects into element o3.element.ZeroLength(osi, [bot_node, top_node], mats=[bilinear_mat], dirs=[o3.cc.DOF2D_X], r_flag=1) # Define the dynamic analysis values = list(-1 * motion) # should be negative acc_series = o3.time_series.Path(osi, dt, values) o3.pattern.UniformExcitation(osi, o3.cc.X, accel_series=acc_series) # set damping based on first eigen mode angular_freq2 = o3.get_eigen(osi, solver='fullGenLapack', n=1) if hasattr(angular_freq2, '__len__'): angular_freq2 = angular_freq2[0] angular_freq = angular_freq2**0.5 beta_k = 2 * xi / angular_freq o3.rayleigh.Rayleigh(osi, alpha_m=0.0, beta_k=beta_k, beta_k_init=0.0, beta_k_comm=0.0) # Run the dynamic analysis o3.wipe_analysis(osi) newmark_gamma = 0.5 newmark_beta = 0.25 o3.algorithm.Newton(osi) o3.constraints.Transformation(osi) o3.algorithm.Newton(osi) o3.numberer.RCM(osi) o3.system.SparseGeneral(osi) o3.integrator.Newmark(osi, newmark_gamma, newmark_beta) o3.analysis.Transient(osi) o3.test_check.EnergyIncr(osi, tol=1.0e-10, max_iter=10) analysis_time = (len(values) - 1) * dt analysis_dt = 0.001 outputs = {"time": [], "rel_disp": [], "rel_accel": [], "force": []} o3.record(osi) curr_time = o3.get_time(osi) while curr_time < analysis_time: outputs["time"].append(curr_time) outputs["rel_disp"].append(o3.get_node_disp(osi, top_node, o3.cc.X)) outputs["rel_accel"].append(o3.get_node_accel(osi, top_node, o3.cc.X)) o3.gen_reactions(osi) outputs["force"].append(-o3.get_node_reaction( osi, bot_node, o3.cc.X)) # Negative since diff node o3.analyze(osi, 1, analysis_dt) curr_time = o3.get_time(osi) o3.wipe(osi) for item in outputs: outputs[item] = np.array(outputs[item]) return outputs
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_analysis(asig, period, xi, f_yield, etype): # Load a ground motion # Define inelastic SDOF mass = 1.0 r_post = 0.0 # Initialise OpenSees instance osi = o3.OpenSeesInstance(ndm=2, state=0) # Establish nodes bot_node = o3.node.Node(osi, 0, 0) top_node = o3.node.Node(osi, 0, 0) # Fix bottom node o3.Fix3DOF(osi, top_node, o3.cc.FREE, o3.cc.FIXED, o3.cc.FIXED) o3.Fix3DOF(osi, bot_node, o3.cc.FIXED, o3.cc.FIXED, o3.cc.FIXED) # Set out-of-plane DOFs to be slaved o3.EqualDOF(osi, top_node, bot_node, [o3.cc.Y, o3.cc.ROTZ]) # nodal mass (weight / g): o3.Mass(osi, top_node, mass, 0., 0.) # Define material k_spring = 4 * np.pi**2 * mass / period**2 bilinear_mat = o3.uniaxial_material.Steel01(osi, fy=f_yield, e0=k_spring, b=r_post) # Assign zero length element, # Note: pass actual node and material objects into element o3.element.ZeroLength(osi, [bot_node, top_node], mats=[bilinear_mat], dirs=[o3.cc.DOF2D_X], r_flag=1) # Define the dynamic analysis # Define the dynamic analysis acc_series = o3.time_series.Path(osi, dt=asig.dt, values=-1 * asig.values) # should be negative o3.pattern.UniformExcitation(osi, dir=o3.cc.X, accel_series=acc_series) # set damping based on first eigen mode angular_freqs = np.array(o3.get_eigen(osi, solver='fullGenLapack', n=1))**0.5 beta_k = 2 * xi / angular_freqs[0] print('angular_freqs: ', angular_freqs) periods = 2 * np.pi / angular_freqs o3.rayleigh.Rayleigh(osi, alpha_m=0.0, beta_k=beta_k, beta_k_init=0.0, beta_k_comm=0.0) # Run the dynamic analysis o3.wipe_analysis(osi) # Run the dynamic analysis 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.SparseGeneral(osi) o3.integrator.Newmark(osi, gamma=0.5, beta=0.25) analysis_dt = 0.01 else: o3.algorithm.Linear(osi, factor_once=True) o3.system.FullGeneral(osi) if etype == 'newmark_explicit': o3.integrator.NewmarkExplicit(osi, gamma=0.6) explicit_dt = periods[0] / np.pi / 32 elif etype == 'central_difference': o3.integrator.CentralDifference(osi) o3.opy.integrator('HHTExplicit') explicit_dt = periods[0] / np.pi / 16 # 0.5 is a factor of safety elif etype == 'explicit_difference': o3.integrator.ExplicitDifference(osi) explicit_dt = periods[0] / np.pi / 32 else: raise ValueError(etype) print('explicit_dt: ', explicit_dt) analysis_dt = explicit_dt o3.analysis.Transient(osi) analysis_time = asig.time[-1] outputs = { "time": [], "rel_disp": [], "rel_accel": [], "rel_vel": [], "force": [] } while o3.get_time(osi) < analysis_time: o3.analyze(osi, 1, analysis_dt) curr_time = o3.get_time(osi) outputs["time"].append(curr_time) outputs["rel_disp"].append(o3.get_node_disp(osi, top_node, o3.cc.X)) outputs["rel_vel"].append(o3.get_node_vel(osi, top_node, o3.cc.X)) outputs["rel_accel"].append(o3.get_node_accel(osi, top_node, o3.cc.X)) o3.gen_reactions(osi) outputs["force"].append(-o3.get_node_reaction( osi, bot_node, o3.cc.X)) # Negative since diff node o3.wipe(osi) for item in outputs: outputs[item] = np.array(outputs[item]) return outputs
def run(show=0): # Load a ground motion record_filename = 'test_motion_dt0p01.txt' asig = eqsig.load_asig(ap.MODULE_DATA_PATH + 'gms/' + record_filename, m=0.5) # Define inelastic SDOF period = 1.0 xi = 0.05 mass = 1.0 f_yield = 1.5 # Reduce this to make it nonlinear r_post = 0.0 # Initialise OpenSees instance osi = o3.OpenSeesInstance(ndm=2, state=0) # Establish nodes bot_node = o3.node.Node(osi, 0, 0) top_node = o3.node.Node(osi, 0, 0) # Fix bottom node o3.Fix3DOF(osi, top_node, o3.cc.FREE, o3.cc.FIXED, o3.cc.FIXED) o3.Fix3DOF(osi, bot_node, o3.cc.FIXED, o3.cc.FIXED, o3.cc.FIXED) # Set out-of-plane DOFs to be slaved o3.EqualDOF(osi, top_node, bot_node, [o3.cc.Y, o3.cc.ROTZ]) # nodal mass (weight / g): o3.Mass(osi, top_node, mass, 0., 0.) # Define material k_spring = 4 * np.pi**2 * mass / period**2 bilinear_mat = o3.uniaxial_material.Steel01(osi, fy=f_yield, e0=k_spring, b=r_post) # Assign zero length element, # Note: pass actual node and material objects into element o3.element.ZeroLength(osi, [bot_node, top_node], mats=[bilinear_mat], dirs=[o3.cc.DOF2D_X], r_flag=1) # Define the dynamic analysis # Define the dynamic analysis acc_series = o3.time_series.Path(osi, dt=asig.dt, values=-1 * asig.values) # should be negative o3.pattern.UniformExcitation(osi, dir=o3.cc.X, accel_series=acc_series) # set damping based on first eigen mode angular_freq = o3.get_eigen(osi, solver='fullGenLapack', n=1)[0]**0.5 beta_k = 2 * xi / angular_freq o3.rayleigh.Rayleigh(osi, alpha_m=0.0, beta_k=beta_k, beta_k_init=0.0, beta_k_comm=0.0) # Run the dynamic analysis o3.wipe_analysis(osi) # Run the dynamic analysis o3.algorithm.Newton(osi) o3.system.SparseGeneral(osi) o3.numberer.RCM(osi) o3.constraints.Transformation(osi) o3.integrator.Newmark(osi, gamma=0.5, beta=0.25) o3.analysis.Transient(osi) o3.test_check.EnergyIncr(osi, tol=1.0e-10, max_iter=10) analysis_time = asig.time[-1] analysis_dt = 0.001 outputs = { "time": [], "rel_disp": [], "rel_accel": [], "rel_vel": [], "force": [] } while o3.get_time(osi) < analysis_time: o3.analyze(osi, 1, analysis_dt) curr_time = o3.get_time(osi) outputs["time"].append(curr_time) outputs["rel_disp"].append(o3.get_node_disp(osi, top_node, o3.cc.X)) outputs["rel_vel"].append(o3.get_node_vel(osi, top_node, o3.cc.X)) outputs["rel_accel"].append(o3.get_node_accel(osi, top_node, o3.cc.X)) o3.gen_reactions(osi) outputs["force"].append(-o3.get_node_reaction( osi, bot_node, o3.cc.X)) # Negative since diff node o3.wipe(osi) for item in outputs: outputs[item] = np.array(outputs[item]) if show: import matplotlib.pyplot as plt plt.plot(outputs['time'], outputs['rel_disp'], label='o3seespy') periods = np.array([period]) # Compare closed form elastic solution from eqsig import sdof resp_u, resp_v, resp_a = sdof.response_series(motion=asig.values, dt=asig.dt, periods=periods, xi=xi) plt.plot(asig.time, resp_u[0], ls='--', label='Elastic') plt.legend() plt.show()
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_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
def get_inelastic_response(fb, roof_drift_ratio=0.05, elastic=False, w_sfsi=False, out_folder=''): """ Run seismic analysis of a nonlinear FrameBuilding Units: Pa, N, m, s Parameters ---------- fb: sfsimodels.Frame2DBuilding object xi Returns ------- """ osi = o3.OpenSeesInstance(ndm=2, state=3) q_floor = 7.0e3 # Pa trib_width = fb.floor_length trib_mass_per_length = q_floor * trib_width / 9.8 # Establish nodes and set mass based on trib area # Nodes named as: C<column-number>-S<storey-number>, first column starts at C1-S0 = ground level left nd = OrderedDict() col_xs = np.cumsum(fb.bay_lengths) col_xs = np.insert(col_xs, 0, 0) n_cols = len(col_xs) sto_ys = fb.heights sto_ys = np.insert(sto_ys, 0, 0) for cc in range(1, n_cols + 1): for ss in range(fb.n_storeys + 1): nd[f"C{cc}-S{ss}"] = o3.node.Node(osi, col_xs[cc - 1], sto_ys[ss]) if ss != 0: if cc == 1: node_mass = trib_mass_per_length * fb.bay_lengths[0] / 2 elif cc == n_cols: node_mass = trib_mass_per_length * fb.bay_lengths[-1] / 2 else: node_mass = trib_mass_per_length * ( fb.bay_lengths[cc - 2] + fb.bay_lengths[cc - 1] / 2) o3.set_node_mass(osi, nd[f"C{cc}-S{ss}"], node_mass, 0., 0.) # Set all nodes on a storey to have the same displacement for ss in range(0, fb.n_storeys + 1): for cc in range(2, n_cols + 1): o3.set_equal_dof(osi, nd[f"C1-S{ss}"], nd[f"C{cc}-S{ss}"], o3.cc.X) # Fix all base nodes for cc in range(1, n_cols + 1): o3.Fix3DOF(osi, nd[f"C{cc}-S0"], o3.cc.FIXED, o3.cc.FIXED, o3.cc.FIXED) # Define material e_conc = 30.0e9 # kPa i_beams = 0.4 * fb.beam_widths * fb.beam_depths**3 / 12 i_columns = 0.5 * fb.column_widths * fb.column_depths**3 / 12 a_beams = fb.beam_widths * fb.beam_depths a_columns = fb.column_widths * fb.column_depths ei_beams = e_conc * i_beams ei_columns = e_conc * i_columns eps_yield = 300.0e6 / 200e9 phi_y_col = calc_yield_curvature(fb.column_depths, eps_yield) phi_y_beam = calc_yield_curvature(fb.beam_depths, eps_yield) # Define beams and columns # Columns named as: C<column-number>-S<storey-number>, first column starts at C1-S0 = ground floor left # Beams named as: B<bay-number>-S<storey-number>, first beam starts at B1-S1 = first storey left (foundation at S0) md = OrderedDict() # material dict sd = OrderedDict() # section dict ed = OrderedDict() # element dict for ss in range(fb.n_storeys): # set columns lp_i = 0.4 lp_j = 0.4 # plastic hinge length col_transf = o3.geom_transf.Linear2D( osi, ) # d_i=[0.0, lp_i], d_j=[0.0, -lp_j] for cc in range(1, fb.n_cols + 1): ele_str = f"C{cc}-S{ss}S{ss + 1}" if elastic: top_sect = o3.section.Elastic2D(osi, e_conc, a_columns[ss][cc - 1], i_columns[ss][cc - 1]) bot_sect = o3.section.Elastic2D(osi, e_conc, a_columns[ss][cc - 1], i_columns[ss][cc - 1]) else: m_cap = ei_columns[ss][cc - 1] * phi_y_col[ss][cc - 1] mat = o3.uniaxial_material.ElasticBilin( osi, ei_columns[ss][cc - 1], 0.05 * ei_columns[ss][cc - 1], 1 * phi_y_col[ss][cc - 1]) mat_axial = o3.uniaxial_material.Elastic( osi, e_conc * a_columns[ss][cc - 1]) top_sect = o3.section.Aggregator(osi, mats=[[mat_axial, o3.cc.P], [mat, o3.cc.M_Z]]) bot_sect = o3.section.Aggregator(osi, mats=[[mat_axial, o3.cc.P], [mat, o3.cc.M_Z]]) centre_sect = o3.section.Elastic2D(osi, e_conc, a_columns[ss][cc - 1], i_columns[ss][cc - 1]) sd[ele_str + "T"] = top_sect sd[ele_str + "B"] = bot_sect sd[ele_str + "C"] = centre_sect integ = o3.beam_integration.HingeMidpoint(osi, bot_sect, lp_i, top_sect, lp_j, centre_sect) bot_node = nd[f"C{cc}-S{ss}"] top_node = nd[f"C{cc}-S{ss + 1}"] ed[ele_str] = o3.element.ForceBeamColumn(osi, [bot_node, top_node], col_transf, integ) print('mc: ', ei_columns[ss][cc - 1] * phi_y_col[ss][cc - 1]) # Set beams lp_i = 0.4 lp_j = 0.4 beam_transf = o3.geom_transf.Linear2D(osi, ) for bb in range(1, fb.n_bays + 1): ele_str = f"C{bb}C{bb + 1}-S{ss + 1}" print('mb: ', ei_beams[ss][bb - 1] * phi_y_beam[ss][bb - 1]) print('phi_b: ', phi_y_beam[ss][bb - 1]) if elastic: left_sect = o3.section.Elastic2D(osi, e_conc, a_beams[ss][bb - 1], i_beams[ss][bb - 1]) right_sect = o3.section.Elastic2D(osi, e_conc, a_beams[ss][bb - 1], i_beams[ss][bb - 1]) else: m_cap = ei_beams[ss][bb - 1] * phi_y_beam[ss][bb - 1] # mat_flex = o3.uniaxial_material.ElasticBilin(osi, ei_beams[ss][bb - 1], 0.05 * ei_beams[ss][bb - 1], phi_y_beam[ss][bb - 1]) mat_flex = o3.uniaxial_material.Steel01(osi, m_cap, e0=ei_beams[ss][bb - 1], b=0.05) mat_axial = o3.uniaxial_material.Elastic( osi, e_conc * a_beams[ss][bb - 1]) left_sect = o3.section.Aggregator(osi, mats=[[mat_axial, o3.cc.P], [mat_flex, o3.cc.M_Z], [mat_flex, o3.cc.M_Y]]) right_sect = o3.section.Aggregator(osi, mats=[[mat_axial, o3.cc.P], [mat_flex, o3.cc.M_Z], [mat_flex, o3.cc.M_Y]]) centre_sect = o3.section.Elastic2D(osi, e_conc, a_beams[ss][bb - 1], i_beams[ss][bb - 1]) integ = o3.beam_integration.HingeMidpoint(osi, left_sect, lp_i, right_sect, lp_j, centre_sect) left_node = nd[f"C{bb}-S{ss + 1}"] right_node = nd[f"C{bb + 1}-S{ss + 1}"] ed[ele_str] = o3.element.ForceBeamColumn(osi, [left_node, right_node], beam_transf, integ) # Apply gravity loads gravity = 9.8 * 1e-2 # If true then load applied along beam g_beams = 0 # TODO: when this is true and analysis is inelastic then failure ts_po = o3.time_series.Linear(osi, factor=1) o3.pattern.Plain(osi, ts_po) for ss in range(1, fb.n_storeys + 1): print('ss:', ss) if g_beams: for bb in range(1, fb.n_bays + 1): ele_str = f"C{bb}C{bb + 1}-S{ss}" o3.EleLoad2DUniform(osi, ed[ele_str], -trib_mass_per_length * gravity) else: for cc in range(1, fb.n_cols + 1): if cc == 1 or cc == n_cols: node_mass = trib_mass_per_length * fb.bay_lengths[0] / 2 elif cc == n_cols: node_mass = trib_mass_per_length * fb.bay_lengths[-1] / 2 else: node_mass = trib_mass_per_length * ( fb.bay_lengths[cc - 2] + fb.bay_lengths[cc - 1] / 2) # This works o3.Load(osi, nd[f"C{cc}-S{ss}"], [0, -node_mass * gravity, 0]) tol = 1.0e-3 o3.constraints.Plain(osi) o3.numberer.RCM(osi) o3.system.BandGeneral(osi) o3.test_check.NormDispIncr(osi, tol, 10) o3.algorithm.Newton(osi) n_steps_gravity = 10 d_gravity = 1. / n_steps_gravity o3.integrator.LoadControl(osi, d_gravity, num_iter=10) o3.analysis.Static(osi) o3.analyze(osi, n_steps_gravity) o3.gen_reactions(osi) print('b1_int: ', o3.get_ele_response(osi, ed['C1C2-S1'], 'force')) print('c1_int: ', o3.get_ele_response(osi, ed['C1-S0S1'], 'force')) # o3.extensions.to_py_file(osi, 'po.py') o3.load_constant(osi, time=0.0) # Define the analysis # set damping based on first eigen mode angular_freq = o3.get_eigen(osi, solver='fullGenLapack', n=1)[0]**0.5 if isinstance(angular_freq, complex): raise ValueError( "Angular frequency is complex, issue with stiffness or mass") print('angular_freq: ', angular_freq) response_period = 2 * np.pi / angular_freq print('response period: ', response_period) # Run the analysis o3r = o3.results.Results2D() o3r.cache_path = out_folder o3r.dynamic = True o3r.pseudo_dt = 0.001 # since analysis is actually static o3.set_time(osi, 0.0) o3r.start_recorders(osi) # o3res.coords = o3.get_all_node_coords(osi) # o3res.ele2node_tags = o3.get_all_ele_node_tags_as_dict(osi) d_inc = 0.0001 o3.numberer.RCM(osi) o3.system.BandGeneral(osi) # o3.test_check.NormUnbalance(osi, 2, max_iter=10, p_flag=2) # o3.test_check.FixedNumIter(osi, max_iter=10) o3.test_check.NormDispIncr(osi, 0.002, 10, p_flag=0) o3.algorithm.Newton(osi) o3.integrator.DisplacementControl(osi, nd[f"C1-S{fb.n_storeys}"], o3.cc.X, d_inc) o3.analysis.Static(osi) d_max = 0.05 * fb.max_height # TODO: set to 5% print('d_max: ', d_max) # n_steps = int(d_max / d_inc) print("Analysis starting") print('int_disp: ', o3.get_node_disp(osi, nd[f"C1-S{fb.n_storeys}"], o3.cc.X)) # opy.recorder('Element', '-file', 'ele_out.txt', '-time', '-ele', 1, 'force') tt = 0 outputs = { 'h_disp': [], 'vb': [], 'REACT-C1C2-S1': [], 'REACT-C1-S0S1': [], } hd = 0 n_max = 2 n_cycs = 0 xs = fb.heights / fb.max_height # TODO: more sophisticated displacement profile ts_po = o3.time_series.Linear(osi, factor=1) o3.pattern.Plain(osi, ts_po) for i, xp in enumerate(xs): o3.Load(osi, nd[f"C1-S{i + 1}"], [xp, 0.0, 0]) # o3.analyze(osi, 2) # n_max = 0 time = [0] while n_cycs < n_max: print('n_cycles: ', n_cycs) for i in range(2): if i == 0: o3.integrator.DisplacementControl(osi, nd[f"C1-S{fb.n_storeys}"], o3.cc.X, d_inc) else: o3.integrator.DisplacementControl(osi, nd[f"C1-S{fb.n_storeys}"], o3.cc.X, -d_inc) while hd * (-1)**i < d_max: ok = o3.analyze(osi, 10) time.append(time[len(time) - 1] + 1) hd = o3.get_node_disp(osi, nd[f"C1-S{fb.n_storeys}"], o3.cc.X) outputs['h_disp'].append(hd) o3.gen_reactions(osi) vb = 0 for cc in range(1, fb.n_cols + 1): vb += o3.get_node_reaction(osi, nd[f"C{cc}-S0"], o3.cc.X) outputs['vb'].append(-vb) outputs['REACT-C1C2-S1'].append( o3.get_ele_response(osi, ed['C1C2-S1'], 'force')) outputs['REACT-C1-S0S1'].append( o3.get_ele_response(osi, ed['C1-S0S1'], 'force')) n_cycs += 1 o3.wipe(osi) o3r.save_to_cache() for item in outputs: outputs[item] = np.array(outputs[item]) print('complete') return outputs
def gen_response(period, xi, asig, etype, fos_for_dt=None): # Define inelastic SDOF mass = 1.0 f_yield = 1.5 # Reduce this to make it nonlinear r_post = 0.0 # Initialise OpenSees instance osi = o3.OpenSeesInstance(ndm=2, state=0) # Establish nodes bot_node = o3.node.Node(osi, 0, 0) top_node = o3.node.Node(osi, 0, 0) # Fix bottom node o3.Fix3DOF(osi, top_node, o3.cc.FREE, o3.cc.FIXED, o3.cc.FIXED) o3.Fix3DOF(osi, bot_node, o3.cc.FIXED, o3.cc.FIXED, o3.cc.FIXED) # Set out-of-plane DOFs to be slaved o3.EqualDOF(osi, top_node, bot_node, [o3.cc.Y, o3.cc.ROTZ]) # nodal mass (weight / g): o3.Mass(osi, top_node, mass, 0., 0.) # Define material k_spring = 4 * np.pi**2 * mass / period**2 # bilinear_mat = o3.uniaxial_material.Steel01(osi, fy=f_yield, e0=k_spring, b=r_post) mat = o3.uniaxial_material.Elastic(osi, e_mod=k_spring) # Assign zero length element, # Note: pass actual node and material objects into element o3.element.ZeroLength(osi, [bot_node, top_node], mats=[mat], dirs=[o3.cc.DOF2D_X], r_flag=1) # Define the dynamic analysis # Define the dynamic analysis acc_series = o3.time_series.Path(osi, dt=asig.dt, values=-1 * asig.values) # should be negative o3.pattern.UniformExcitation(osi, dir=o3.cc.X, accel_series=acc_series) # set damping based on first eigen mode angular_freq = o3.get_eigen(osi, solver='fullGenLapack', n=1)[0]**0.5 period = 2 * np.pi / angular_freq beta_k = 2 * xi / angular_freq o3.rayleigh.Rayleigh(osi, alpha_m=0.0, beta_k=beta_k, beta_k_init=0.0, beta_k_comm=0.0) o3.set_time(osi, 0.0) # Run the dynamic analysis o3.wipe_analysis(osi) # Run the dynamic analysis o3.numberer.RCM(osi) o3.system.FullGeneral(osi) if etype == 'central_difference': o3.algorithm.Linear(osi, factor_once=True) o3.integrator.CentralDifference(osi) explicit_dt = 2 / angular_freq / fos_for_dt analysis_dt = explicit_dt elif etype == 'implicit': o3.algorithm.Newton(osi) o3.integrator.Newmark(osi, gamma=0.5, beta=0.25) analysis_dt = 0.001 else: raise ValueError() o3.constraints.Transformation(osi) o3.analysis.Transient(osi) o3.test_check.EnergyIncr(osi, tol=1.0e-10, max_iter=10) analysis_time = asig.time[-1] outputs = { "time": [], "rel_disp": [], "rel_accel": [], "rel_vel": [], "force": [] } rec_dt = 0.002 n_incs = int(analysis_dt / rec_dt) n_incs = 1 while o3.get_time(osi) < analysis_time: o3.analyze(osi, n_incs, analysis_dt) curr_time = o3.get_time(osi) outputs["time"].append(curr_time) outputs["rel_disp"].append(o3.get_node_disp(osi, top_node, o3.cc.X)) outputs["rel_vel"].append(o3.get_node_vel(osi, top_node, o3.cc.X)) outputs["rel_accel"].append(o3.get_node_accel(osi, top_node, o3.cc.X)) o3.gen_reactions(osi) outputs["force"].append(-o3.get_node_reaction( osi, bot_node, o3.cc.X)) # Negative since diff node o3.wipe(osi) for item in outputs: outputs[item] = np.array(outputs[item]) return outputs