"""OpenSees Example 1a. 2D Elastic Cantilever Column. OpenSees Wiki: https://opensees.berkeley.edu/wiki/index.php?title=OpenSees_Example_1a._2D_Elastic_Cantilever_Column This model keeps the original Example 1a geometry and packages both lateral-load variants into a single OTKO project: - Gravity preload in 10 static LoadControl steps - Displacement-controlled static pushover - UniformExcitation ground-motion analysis using ``BM68elc.acc`` Run from the repository root: python examples/ex1a_canti2d.py Produces ``examples/ex1a_canti2d.osmodel``. """ from __future__ import annotations from pathlib import Path import sys if __package__ is None or __package__ == "": sys.path.insert(0, str(Path(__file__).resolve().parents[1] / "src")) from otko.core import ( # noqa: E402 ElasticBeamColumn, ElasticSection, LinearTimeSeries, NodalLoad, Node, PathTimeSeries, PlainLoadPattern, Project, ProjectMeta, PushoverCase, StaticCase, TransientCase, UniformExcitationPattern, UnitSystem, ) from otko.services import load_project, save_project # noqa: E402 from otko.services.peer_record import parse_plain_values # noqa: E402 COLUMN_HEIGHT = 432.0 TOP_WEIGHT = 2000.0 TOP_MASS_X = 5.18 TOP_MASS_Y = 1.0e-9 AREA = 3_600_000_000.0 E_MODULUS = 4227.0 IZ = 1_080_000.0 PUSH_STEP = 0.1 PUSH_TARGET = 100.0 GROUND_DT = 0.01 GROUND_FACTOR = 1.0 ANALYSIS_DT = 0.02 ANALYSIS_STEPS = 1000 DAMPING_RATIO = 0.02 _ROOT = Path(__file__).resolve().parent GROUND_MOTION_FILE = _ROOT / "data" / "BM68elc.acc" REFERENCE_PUSH_TCL = _ROOT / "data" / "Ex1a.Canti2D.Push.tcl.txt" REFERENCE_EQ_TCL = _ROOT / "data" / "Ex1a.Canti2D.EQ.tcl.txt" def _ground_motion_values() -> list[float]: return parse_plain_values(GROUND_MOTION_FILE) def build_ex1a_canti2d() -> Project: values = _ground_motion_values() return Project( meta=ProjectMeta( name="OpenSees Ex 1a - 2D Elastic Cantilever Column", author="OpenSees Wiki / Silvia Mazzoni & Frank McKenna", description=( "Original Ex 1a elastic cantilever column with shared gravity " "preload, static pushover, and BM68elc base-excitation cases." ), units=UnitSystem.US_IN_KIP, ), ndm=2, ndf=3, nodes=[ Node( id=1, name="Base", coords=(0.0, 0.0, 0.0), restraint=(True, True, False, False, False, True), ), Node( id=2, name="Top", coords=(0.0, COLUMN_HEIGHT, 0.0), mass=(TOP_MASS_X, TOP_MASS_Y, 0.0, 0.0, 0.0, 0.0), ), ], sections=[ ElasticSection( id=1, name="Column-Elastic", E=E_MODULUS, A=AREA, Iz=IZ, Iy=IZ, G=1.0, J=1.0, ), ], elements=[ ElasticBeamColumn( id=1, name="Column", nodes=(1, 2), section_id=1, geom_transf="Linear", ), ], time_series=[ LinearTimeSeries(id=1, name="Gravity"), LinearTimeSeries(id=2, name="Lateral"), PathTimeSeries( id=3, name="BM68elc", dt=GROUND_DT, factor=GROUND_FACTOR, values=values, file_path=str(GROUND_MOTION_FILE.name), ), ], load_patterns=[ PlainLoadPattern( id=1, name="Gravity", time_series_id=1, nodal_loads=[ NodalLoad( node_id=2, forces=(0.0, -TOP_WEIGHT, 0.0, 0.0, 0.0, 0.0), ), ], ), PlainLoadPattern( id=2, name="Pushover-X", time_series_id=2, nodal_loads=[ NodalLoad( node_id=2, forces=(TOP_WEIGHT, 0.0, 0.0, 0.0, 0.0, 0.0), ), ], ), UniformExcitationPattern( id=3, name="GroundMotion-X", direction=1, accel_series_id=3, ), ], analyses=[ StaticCase( id=1, name="Gravity", pattern_ids=[1], n_steps=10, load_factor_increment=0.1, system="BandGeneral", constraints="Plain", integrator="LoadControl", algorithm="Newton", test="NormDispIncr", tolerance=1e-8, max_iter=6, ), PushoverCase( id=2, name="Push", preload_case_ids=[1], pattern_ids=[2], control_node=2, control_dof=1, target_disp=PUSH_TARGET, step_size=PUSH_STEP, base_nodes=[1], system="BandGeneral", constraints="Plain", algorithm="Newton", test="NormDispIncr", tolerance=1e-8, max_iter=6, ), TransientCase( id=3, name="Earthquake", preload_case_ids=[1], pattern_ids=[3], dt=ANALYSIS_DT, n_steps=ANALYSIS_STEPS, system="BandGeneral", constraints="Plain", integrator="Newmark", integrator_params=(0.5, 0.25), algorithm="Newton", test="NormDispIncr", tolerance=1e-8, max_iter=10, rayleigh_mode1_damping=DAMPING_RATIO, ), ], ) def main() -> None: project = build_ex1a_canti2d() project.validate_references() gm = next(ts for ts in project.time_series if ts.id == 3) assert isinstance(gm, PathTimeSeries) print(f"Built '{project.meta.name}'") print(f" Gravity + pushover + earthquake cases: {len(project.analyses)}") print(f" Ground motion file: {GROUND_MOTION_FILE.name}") print(f" Reference Tcls: {REFERENCE_PUSH_TCL.name}, {REFERENCE_EQ_TCL.name}") print(f" Record points: {len(gm.values)}, dt = {GROUND_DT}s, factor = {GROUND_FACTOR}") out_path = Path(__file__).with_suffix(".osmodel") save_project(project, out_path) print(f"Saved -> {out_path}") restored = load_project(out_path) restored.validate_references() assert restored.model_dump(by_alias=True) == project.model_dump(by_alias=True) print("Round-trip OK.") if __name__ == "__main__": main()