FESADev/docs/releases/euler-beam-3d-release.md

3D Euler-Bernoulli Beam Kernel Release Readiness Note

Metadata

• feature_id: euler-beam-3d
• source_requirement: docs/requirements/euler-beam-3d.md
• source_formulation: docs/formulations/euler-beam-3d-formulation.md
• source_numerical_review: docs/numerical-reviews/euler-beam-3d-review.md
• source_io_definition: docs/io-definitions/euler-beam-3d-io.md
• source_reference_model: docs/reference-models/euler-beam-3d-reference-models.md
• source_implementation_plan: docs/implementation-plans/euler-beam-3d-implementation-plan.md
• source_build_test_report: docs/build-test-reports/euler-beam-3d-build-test.md
• source_reference_verification_report: N/A
• source_physics_evaluation_report: N/A
• status: not-release-ready-kernel-increment-complete
• owner_agent: release-agent
• date: 2026-06-12

Release Scope

item	included	excluded	notes
analysis_type	element kernel calculations	full linear static solve	Solver integration is not complete.
element_type	two-node straight prismatic 3D Euler-Bernoulli beam kernel	Timoshenko beams, curved beams, offsets, releases, warping	Kernel scope only.
material_model	positive finite E and G constants supplied to the kernel	material parser or library integration	No material database integration.
section_model	positive finite A, J, Iy, Iz constants supplied to the kernel	beam section parser/property integration	Future I/O phase required.
output_quantities	local/global stiffness and local/global end forces returned in memory	HDF5 results, reference CSV views, stress recovery	Authoritative output path is future work.

Completed Kernel Increment

• Added semantic ElementTopology::beam2.
• Added local 12x12 Euler-Bernoulli beam stiffness for axial, torsion, and two bending planes.
• Added local end-force recovery as K_local * u_local.
• Added local axis construction from two nodes plus an orientation vector.
• Added global stiffness transformation using K_global = T^T K_local T.
• Added global end-force recovery using the same transformation convention.
• Added unit tests for topology, local stiffness entries, local symmetry, local force recovery, invalid local inputs, identity transform, rotated symmetry, rigid translation, axial extension, parallel orientation, and zero orientation.

Missing For Full Feature Release

• Parser implementation for the approved Abaqus subset.
• Beam section/property semantic model integration.
• Material-to-section mapping for E, G, A, J, Iy, and Iz.
• Assembler and static solver integration.
• HDF5 result emission for beam displacement, reaction, and internal force quantities.
• Stored Abaqus reference artifacts under reference/<model-id>/.
• Reference comparison report.
• Physics sanity report.
• Final release report with all upstream gates passing.

Gate Evidence Inventory

gate	source	expected_status	observed_status	verdict
requirements	docs/requirements/euler-beam-3d.md	sufficient for kernel	draft with explicit kernel scope	pass for kernel
research	docs/research/euler-beam-3d-research.md	ready-for-formulation	ready-for-formulation	pass
formulation	docs/formulations/euler-beam-3d-formulation.md	ready-for-numerical-review	ready-for-numerical-review	pass
numerical_review	docs/numerical-reviews/euler-beam-3d-review.md	pass-for-implementation-planning	pass-for-implementation-planning	pass
io_definition	docs/io-definitions/euler-beam-3d-io.md	future integration contract	ready-for-implementation-planning	pass for planning
reference_model	docs/reference-models/euler-beam-3d-reference-models.md	artifacts present for release	needs-reference-artifacts	fail for release
implementation	source and tests	implemented kernel	implemented kernel	pass for kernel
build_test	docs/build-test-reports/euler-beam-3d-build-test.md	pass	pass-for-reference-verification	pass
reference_verification	docs/reference-verifications/euler-beam-3d-reference-verification.md	pass-for-physics-evaluation	missing	fail for release
physics_evaluation	docs/physics-evaluations/euler-beam-3d-physics-evaluation.md	pass-for-release-agent	missing	fail for release

Acceptance Traceability

requirement_id	release_disposition
EB3D-REQ-001 through EB3D-REQ-011	Implemented and unit-tested at kernel level. Full solver evidence deferred.
EB3D-REQ-012	Excluded behaviors remain out of scope.
EB3D-REQ-013	No reference artifacts were created or modified.
EB3D-REQ-014	No full Abaqus compatibility claim is made.
EB3D-REQ-015	Kernel completion is explicitly separate from full solver release readiness.

Validation Evidence

command_or_report	expected	observed	notes
ctest --test-dir build/msvc-debug --output-on-failure -C Debug -R "model_element_test|euler_beam_3d_(local_stiffness|transform_recovery)_test"	pass	pass, 3/3 tests	Feature-specific CTest filter passed.
python -m unittest discover -s scripts -p "test_*.py"	pass	pass, 104 tests	Harness self-test passed.
python scripts/validate_workspace.py	pass	pass, 23/23 CTests	Used absolute CMake/CTest commands through HARNESS_VALIDATION_COMMANDS.

Known Limitations

limitation	category	user_impact	disposition
No parser support for beam input yet.	input	Users cannot run beam .inp models end-to-end.	deferred
No section/property model integration.	model	Constants must be supplied directly to the kernel API.	deferred
No assembly/static solver integration.	solver	Beam elements do not contribute to a global system yet.	deferred
No HDF5 result output for beam quantities.	output	No official solver output exists for beam results.	deferred
No reference artifacts or comparison report.	verification	Full solver correctness against Abaqus is not established.	blocker for release
No stress or strain recovery.	physics/output	Stress CSV and stress HDF5 datasets are not available.	deferred
No shear deformation, warping, releases, offsets, mass, geometric stiffness, nonlinear, dynamic, or thermal behavior.	physics	Feature is limited to the approved Euler-Bernoulli kernel.	documented

Release Notes Draft

Feature Summary

• Kernel increment for a two-node 3D Euler-Bernoulli beam element is complete.

Verification Scope

• Unit-tested local stiffness, local end forces, global transform, global end forces, and invalid geometry/section handling.

Main Limitations

• This is not an end-to-end solver feature. Parser, assembly, HDF5 output, reference comparison, and physics sanity remain future gates.

Artifacts

• docs/build-test-reports/euler-beam-3d-build-test.md
• docs/requirements/euler-beam-3d.md
• docs/formulations/euler-beam-3d-formulation.md
• docs/reference-models/euler-beam-3d-reference-models.md

Release Verdict

• verdict: not-release-ready-kernel-increment-complete
• reason: kernel implementation and build/test validation are complete, but full feature release lacks parser integration, HDF5 output, reference artifacts, reference verification, and physics sanity evidence.

Handoff Recommendation

target_agent	reason	required_input
Coordinator Agent	Decide next phase sequencing.	This release note and phase index.
I/O Definition Agent	Finalize exact Abaqus beam subset and section/orientation keywords.	Current I/O contract and kernel API behavior.
Reference Model Agent	Generate approved future reference artifact contracts and then artifacts in an explicit phase.	Reference model contract.
Implementation Agent	Integrate kernel into parser/model/assembly only after upstream contracts are approved.	Implementation plan and build/test report.

No-Change Assertion

• source_files_modified: false in this release note step.
• test_files_modified: false in this release note step.
• cmake_files_modified: false.
• reference_artifacts_modified: false.
• tolerance_policies_modified: false.

Open Issues

• Full solver release remains blocked until the missing gates listed above are completed.