AIXC-MAT-DS-001

Verified science dossier

Shell-to-bottom weld joint · vertical atmospheric water tank · S275JR

Every figure in this dossier links to its results file, with its SHA-256, and to its verification. The execution log is attached and the engineer's attestation is the step that completes the dossier. A dossier is released signed, except sample dossiers such as this one, which are published in the UNSIGNED state.

Dossier
AIXC-MAT-DS-001
Status
UNSIGNED
Run
AIXC-MAT-RUN-A-20261017
Engines
gmsh · CalculiX 2.23

Execution trace

The AI Scientist's five steps on this case. Each step opens its evidence.

  1. Plan

    Geometry and material definition: Ø 6 m, shell 8 m × 6 mm, bottom plate 8 mm, 6 mm leg fillet welds, S275JR steel. Axisymmetric solid model (CAX8), hydrostatic water pressure (ρ = 1000 kg/m³). Three meshes with t/2, t/4 and t/8 element sizes in the joint zone.

    Evidence

    EvidencePAR dict in fe/demos/deposito_virola_fondo.py

    Logrun AIXC-MAT-RUN-A-20261017: SHA-256 of fe/demos/deposito_virola_fondo.py = 351d8b7497f46b459314c878f24f0d8c19e543405c618aea4e20da8fad62af7d and of fe/params_generico.json = 9376f428844f562be4149b58a5b4ff721c4b3865fe33aefede978790f4a212d6, recorded in fe/resultados_demos/A/ejecucion-2026-10-17/registro_ejecucion.json

  2. Extract

    Mesh generation with gmsh and reading of the displacement field from the CalculiX .frd file. Interpolation of σ_hs (5/3 · σ(0.4 t) − 2/3 · σ(1.0 t)) at the four weld toes (inner/outer × shell/bottom).

    Evidence

    EvidenceFunctions mallar() and leer_campo() in fe/demos/comun.py and fe/demos/deposito_virola_fondo.py

    Logrun AIXC-MAT-RUN-A-20261017: fe/resultados_demos/A/ejecucion-2026-10-17/ejecucion.log (stdout and stderr of the three CalculiX runs) and fe/resultados_demos/A/ejecucion-2026-10-17/registro_ejecucion.json (SHA-256 of every .inp, .msh, .dat, .sta and .cvg); the .dat, .sta and .cvg files travel inside the dossier package under run-log/

  3. Compute

    Three CalculiX runs (axisymmetric, linear elastic). Nodal reactions of the 2° sector are multiplied by 180 to obtain the total force. Analytical verification (clamped cylindrical shell, Timoshenko-Woinowsky-Krieger ch. 15) computed in the same script.

    Evidence

    Evidencefe/demos/deposito_virola_fondo.py

    Logrun AIXC-MAT-RUN-A-20261017: three ccx jobs recorded in fe/resultados_demos/A/ejecucion-2026-10-17/ejecucion.log; versions of ccx, gmsh, python and numpy, git commit, SHA-256 of every input script and of each .inp, .msh, .dat, .sta and .cvg are kept in fe/resultados_demos/A/ejecucion-2026-10-17/registro_ejecucion.json; comparison against the current resultados_A.json: 264 keys equal, 0 differ (relative tolerance 1e-9) in fe/resultados_demos/A/ejecucion-2026-10-17/comparacion.json

  4. Verify

    Mesh convergence: relative change t/4 → t/8 = 1.30% (outer shell toe); convergence criterion of the calculation: 5% (key pasa_5pct). Bottom plate toes do not pass but their |σ_hs| is below 10% of the critical toe. Analytical verification: max σ_x inner error = 0.12% of peak. Equilibrium: error 0.0002%.

    Evidence

    Evidencefe/resultados_demos/A/resultados_A.json

    Logkeys convergencia and verificacion_analitica in resultados_A.json

  5. Report

    Figures generated by figuras_demos.py (1600 × 900 px): stress map with IIW read-off points (fe-a-mapa-es/en) and S-N curve with the computed point (fe-a-sn-es/en). Dossier generated by generar_dossier.py (this script).

    Evidence

    Evidencefe/demos/figuras_demos.py; dem-web/dossier/generar_dossier.py

    Logfigure hashes in manifest.json

Execution record

Run AIXC-MAT-RUN-A-20261017 repeats the calculation with a full record: command, timings, versions and the SHA-256 fingerprint of every input and output. All of it ships in the .zip package.

run_id
AIXC-MAT-RUN-A-20261017
Start (UTC)
2026-10-17T18:32:02+00:00
End (UTC)
2026-10-17T18:32:32+00:00
Duration
30.0 s
Exit code
0
CalculiX
2.23 (ccx -v)
gmsh
4.15.2
Python · numpy
3.14.7 · 2.5.3
Platform
Darwin 25.6.0 arm64

Command, run from the project folder (relative paths):

~/.venvs/planos/bin/python -u fe/demos/deposito_virola_fondo.py --tmp fe/resultados_demos/A/ejecucion-2026-10-17/trabajo --out fe/resultados_demos/A/ejecucion-2026-10-17/salida
SHA-256 of the inputs (7 scripts and parameters)
fe/demos/deposito_virola_fondo.py351d8b7497f46b459314c878f24f0d8c19e543405c618aea4e20da8fad62af7d
fe/demos/comun.py21fb80111082a5b3722c47dab32816fcad2e729028d113a755476b941be43fb5
fe/a4_modelo.pyc7925691ad2bbf2934557bd1f5ff26ece3d7e70e7cc02a3ab780bbd26f88b749
fe/fatiga.py3560219f3f483eb169a933ea2cd85e6ed92334690ce2384f6a8e024b58f8fcb9
fe/punto_caliente.py109374118bcfe572d8fb746ffab7dceb8a8d1b0a684a7735a475f58fd085380b
fe/params_generico.json9376f428844f562be4149b58a5b4ff721c4b3865fe33aefede978790f4a212d6
fe/demos/ejecutar_con_registro.py432ce44e6e5e7837a037323761a267ded83e7894388825277e4e36643026ebf4
SHA-256 of the outputs (16 CalculiX files, 2 results files and the console log)
fe/resultados_demos/A/ejecucion-2026-10-17/trabajo/empotrado/modelo.cvg65086dedb4572132b815ace04b294909c7f6f337111f9704fc310b02320f67f7
fe/resultados_demos/A/ejecucion-2026-10-17/trabajo/empotrado/modelo.dat62d39d92d04ab1fd47b41a10552efd7f2ff9d768075908466edcb037a9935b60
fe/resultados_demos/A/ejecucion-2026-10-17/trabajo/empotrado/modelo.inpe6719a906b573c9730cc08d9ecef7c0057bafbcfcbcc0e362e07b2b4731304b0
fe/resultados_demos/A/ejecucion-2026-10-17/trabajo/empotrado/modelo.sta01e324ec0ea28f4d1fd7f5e2da1277af53812b873e218be1604c17a4c8e4990d
fe/resultados_demos/A/ejecucion-2026-10-17/trabajo/prod_t_2/modelo.cvg65086dedb4572132b815ace04b294909c7f6f337111f9704fc310b02320f67f7
fe/resultados_demos/A/ejecucion-2026-10-17/trabajo/prod_t_2/modelo.dat53c868b55555505da96e6867d668719e34a8d59211a22fe77d1eb174475a2870
fe/resultados_demos/A/ejecucion-2026-10-17/trabajo/prod_t_2/modelo.inp578525f946896fc70cd745759631173c7fe3331cf06602a667f263665d724cad
fe/resultados_demos/A/ejecucion-2026-10-17/trabajo/prod_t_2/modelo.sta01e324ec0ea28f4d1fd7f5e2da1277af53812b873e218be1604c17a4c8e4990d
fe/resultados_demos/A/ejecucion-2026-10-17/trabajo/prod_t_4/modelo.cvg65086dedb4572132b815ace04b294909c7f6f337111f9704fc310b02320f67f7
fe/resultados_demos/A/ejecucion-2026-10-17/trabajo/prod_t_4/modelo.dateb63a5af9c84154e47fee83f23e5efd4415c673f2651df8161fe0e0c1988833f
fe/resultados_demos/A/ejecucion-2026-10-17/trabajo/prod_t_4/modelo.inp892e064ccfeccd70bf2396323dd8e6ea35871c374cf2565304e8b77e44eea763
fe/resultados_demos/A/ejecucion-2026-10-17/trabajo/prod_t_4/modelo.sta01e324ec0ea28f4d1fd7f5e2da1277af53812b873e218be1604c17a4c8e4990d
fe/resultados_demos/A/ejecucion-2026-10-17/trabajo/prod_t_8/modelo.cvg65086dedb4572132b815ace04b294909c7f6f337111f9704fc310b02320f67f7
fe/resultados_demos/A/ejecucion-2026-10-17/trabajo/prod_t_8/modelo.dat9fa8c87e08bc49cc919d0638668712edaba51f564f4513b3cf8d59153586b54a
fe/resultados_demos/A/ejecucion-2026-10-17/trabajo/prod_t_8/modelo.inpf42ad2db8a164ec260062d1f893e45f7924918eec222e4ecc60deafaaa6f2df9
fe/resultados_demos/A/ejecucion-2026-10-17/trabajo/prod_t_8/modelo.sta01e324ec0ea28f4d1fd7f5e2da1277af53812b873e218be1604c17a4c8e4990d
fe/resultados_demos/A/ejecucion-2026-10-17/salida/campo_A.npzf9ce02928bdd89c02fe8772643ef71596376c2752608e8fccc044f10871ab449
fe/resultados_demos/A/ejecucion-2026-10-17/salida/resultados_A.jsonca7d9556a4c8ad8d5faf0585dea77916039a99d1a850041c745e23036e83ad39
fe/resultados_demos/A/ejecucion-2026-10-17/ejecucion.logb8ce5042c435222bea22cd7b3823ab1c9099df6a11b5b95d66de5740c5592714

Comparison with the current results: 264 keys equal and 0 different, at a relative tolerance of 1·10⁻⁹. The .frd files are not shipped in the package because of their size; the log identifies them by SHA-256.

Claims

Each claim carries its value, its source key and the fingerprint of the file it comes from.

IDClaimValueTypeEvidence
CLAIM-001 The IIW type-a structural hot-spot stress at the outer shell weld toe (meridional component σ_z at the surface) is Δσ_hs = 64.9 MPa at the t/8 mesh (element size 0.750 mm, 10433 elements). Range computed as the difference between full-load and unloaded states (equals full-load in linear analysis). 64.86 MPa Conclusion
show the fragment
{ "claim_id": "CLAIM-001", "run_id": "AIXC-MAT-RUN-A-20261017", "source_key": "mallas.t/8.punto_caliente.exterior_virola.sigma_hs_Pa", "sha256_source": "sha256:ca7d9556a4c8ad8d5faf0585dea77916039a99d1a850041c745e23036e83ad39", "sha256_registro_ejecucion": "sha256:18eb27a04b120c9c231255f50fa310f5f2386499acd19c1bcb9518992ad2f981", "source_resultados_run": "fe/resultados_demos/A/ejecucion-2026-10-17/salida/resultados_A.json", "value": 64.86, "verification": { "type": "mesh_convergence", "description_es": "Cambio relativo t/4 → t/8 en el pie exterior de la virola: 1,30 % (interior virola: 1,84 %); criterio de convergencia del cálculo: 5 % (clave pasa_5pct). Pie interior del fondo: 42,8 % (no supera el criterio; pie con |σ_hs| < 10 % del pie crítico: el cambio relativo no es significativo y no se usa). Pie exterior del fondo: 18,7 % (no supera el criterio; pie con |σ_hs| < 10 % del pie crítico: el cambio relativo no es significativo y no se usa).", "description_en": "Relative change t/4 → t/8 at the outer shell toe: 1.30 % (inner shell: 1.84 %); convergence criterion of the calculation: 5 % (key pasa_5pct). Inner bottom toe: 42.8 % (does not pass; toe with |σ_hs| < 10 % of the critical toe: the relative change is not significant and is not used). Outer bottom toe: 18.7 % (does not pass; toe with |σ_hs| < 10 % of the critical toe: the relative change is not significant and is not used).", "value_pct": 1.3, "passes_threshold": true } }
CLAIM-002 Mesh convergence at the outer shell hot-spot is 1.30% (relative change between the t/4 and t/8 meshes), within the calculation convergence criterion of 5% (key pasa_5pct). Bottom plate toes (inner 42.8% and outer 18.7%) do not pass the criterion, but their |σ_hs| is below 10% of the critical toe and are not used. 1.3 % Conclusion
show the fragment
{ "claim_id": "CLAIM-002", "run_id": "AIXC-MAT-RUN-A-20261017", "source_key": "convergencia.exterior_virola.cambio_ultimo_par_pct", "sha256_source": "sha256:ca7d9556a4c8ad8d5faf0585dea77916039a99d1a850041c745e23036e83ad39", "sha256_registro_ejecucion": "sha256:18eb27a04b120c9c231255f50fa310f5f2386499acd19c1bcb9518992ad2f981", "source_resultados_run": "fe/resultados_demos/A/ejecucion-2026-10-17/salida/resultados_A.json", "value": 1.3, "verification": { "type": "self", "description_es": "Calculado desde los dos valores de σ_hs en mallas t/4 y t/8, ambos en convergencia.exterior_virola.valores.", "description_en": "Computed from the two σ_hs values at t/4 and t/8 meshes, both in convergencia.exterior_virola.valores." } }
CLAIM-003 With Δσ_hs = 64.9 MPa and 365 cycles/year, the characteristic fatigue life of the shell-to-bottom weld joint (EN 1993-1-9 S-N curve shape, FAT 90 load-carrying fillet, γ_Mf = 1.00) is 5.59×10⁶ cycles (15,305 years). With γ_Mf = 1.35 (safe-life): 2.17×10⁶ cycles (5,951 years). FAT 90, γ_Mf 1.00: 5.59×10⁶ cycles / 15,305 years Conclusion
show the fragment
{ "claim_id": "CLAIM-003", "run_id": "AIXC-MAT-RUN-A-20261017", "source_key": "fatiga.resultado", "sha256_source": "sha256:ca7d9556a4c8ad8d5faf0585dea77916039a99d1a850041c745e23036e83ad39", "sha256_registro_ejecucion": "sha256:18eb27a04b120c9c231255f50fa310f5f2386499acd19c1bcb9518992ad2f981", "source_resultados_run": "fe/resultados_demos/A/ejecucion-2026-10-17/salida/resultados_A.json", "value": { "FAT90_gMf100_ciclos": 5586399.0, "FAT90_gMf100_anios": 15305.0, "FAT90_gMf135_ciclos": 2172030.0, "FAT90_gMf135_anios": 5951.0 }, "verification": { "type": "curva_sn", "description_es": "Curva S-N de forma EN 1993-1-9 (m = 3 hasta 5·10⁶ ciclos, m = 5 hasta 10⁸, umbral de corte). FAT 90 es la tensión de referencia a 2·10⁶ ciclos; el parámetro de fatiga publicado en las figuras queda en fatiga.resultado.valor_publicado_en_figuras (clave FAT90_gMf1,00).", "description_en": "S-N curve shape EN 1993-1-9 (m = 3 up to 5×10⁶ cycles, m = 5 up to 10⁸, cut-off). FAT 90 is the reference stress at 2×10⁶ cycles; the figure-published fatigue parameter is recorded in fatiga.resultado.valor_publicado_en_figuras (key FAT90_gMf1,00)." } }
CLAIM-004 Analytical verification: cylindrical shell clamped at the base, no bottom plate, against the elastic-foundation thin-shell solution (Timoshenko & Woinowsky-Krieger, Theory of Plates and Shells, ch. 15). Maximum σ_x error on the inner face: 0.12 % of peak (from z = 2 t to 4 m). 0.124 % of peak Reference
show the fragment
{ "claim_id": "CLAIM-004", "run_id": "AIXC-MAT-RUN-A-20261017", "source_key": "verificacion_analitica.error_max_sigma_x_int_pct_del_maximo", "sha256_source": "sha256:ca7d9556a4c8ad8d5faf0585dea77916039a99d1a850041c745e23036e83ad39", "sha256_registro_ejecucion": "sha256:18eb27a04b120c9c231255f50fa310f5f2386499acd19c1bcb9518992ad2f981", "source_resultados_run": "fe/resultados_demos/A/ejecucion-2026-10-17/salida/resultados_A.json", "value": 0.124, "verification": { "type": "exact_solution", "description_es": "La solución exacta de la lámina delgada se recalcula en el script deposito_virola_fondo.py (función beta, solución en z). No se usa en la base (z < 2 t) porque el sólido bloquea la contracción de Poisson.", "description_en": "The exact thin-shell solution is recomputed in the script deposito_virola_fondo.py (beta function, z-domain solution). Not used at the base (z < 2 t) because the solid element locks Poisson contraction." } }
CLAIM-005 Circumferential membrane stress at 0.3 m from the base: one-foot formula (EN 14015) 37.81 MPa, FE result 39.25 MPa (FE/formula ratio 1.038). Base flexion still affects this level (2.9/β); at 2 m the ratio is 0.999. formula 37.81 MPa; FE 39.25 MPa Reference
show the fragment
{ "claim_id": "CLAIM-005", "run_id": "AIXC-MAT-RUN-A-20261017", "source_key": "metodo_del_pie", "sha256_source": "sha256:ca7d9556a4c8ad8d5faf0585dea77916039a99d1a850041c745e23036e83ad39", "sha256_registro_ejecucion": "sha256:18eb27a04b120c9c231255f50fa310f5f2386499acd19c1bcb9518992ad2f981", "source_resultados_run": "fe/resultados_demos/A/ejecucion-2026-10-17/salida/resultados_A.json", "value": { "formula_MPa": 37.81, "fe_MPa": 39.25, "cociente": 1.038 }, "verification": { "type": "formula_comparison", "description_es": "Fórmula del método del pie (one-foot) de EN 14015 y API 650 frente al campo FE en el mismo nodo.", "description_en": "One-foot formula of EN 14015 / API 650 vs FE field at the same node." } }
CLAIM-META-001 Run parameters: axisymmetric CalculiX (CAX8/CAX6), gmsh, Python. Three meshes (t/2, t/4, t/8 of the shell) in the joint zone. Deterministic; no random seed. {"mallas": ["t/2", "t/4", "t/8"], "n_elementos": {"t/2": 8425, "t/4": 8850, "t/8": 10433}, "tamano_elemento_union_m": {"t/2": 0.003, "t/4": 0.0015, "t/8": 0.00075}}
show the fragment
{ "claim_id": "CLAIM-META-001", "run_id": "AIXC-MAT-RUN-A-20261017", "source_key": "mallas", "sha256_source": "sha256:ca7d9556a4c8ad8d5faf0585dea77916039a99d1a850041c745e23036e83ad39", "sha256_registro_ejecucion": "sha256:18eb27a04b120c9c231255f50fa310f5f2386499acd19c1bcb9518992ad2f981", "source_resultados_run": "fe/resultados_demos/A/ejecucion-2026-10-17/salida/resultados_A.json", "value": { "mallas": [ "t/2", "t/4", "t/8" ], "n_elementos": { "t/2": 8425, "t/4": 8850, "t/8": 10433 }, "tamano_elemento_union_m": { "t/2": 0.003, "t/4": 0.0015, "t/8": 0.00075 } }, "verification": null }

Figures

Meridional stress map (σ_z). IIW read-off points (type a): 0.4 t and 1.0 t from the outer weld toe. Demonstration on generic geometry.
Fig. 1. Meridional stress map (σ_z). IIW read-off points (type a): 0.4 t and 1.0 t from the outer weld toe. Demonstration on generic geometry.
S-N curve EN 1993-1-9 shape. FAT 90 (load-carrying fillet), γ_Mf = 1.00. Δσ_hs = 64.9 MPa → 15,305 years. Demonstration on generic geometry.
Fig. 2. S-N curve EN 1993-1-9 shape. FAT 90 (load-carrying fillet), γ_Mf = 1.00. Δσ_hs = 64.9 MPa → 15,305 years. Demonstration on generic geometry.

Signature

UNSIGNEDChartered industrial engineer, COIIAR no. 2653

The signatory's attestation of the results recorded here; it is not a qualified electronic signature.

SHA-256 of evidence_dossier.json (bytes of the published file, also inside the .zip):sha256:e95623e62df29e82ef97c415e4b2e0c42e5ba53b3db138a26e48deb13cf51289

SHA-256 of fe/resultados_demos/A/resultados_A.json:sha256:ca7d9556a4c8ad8d5faf0585dea77916039a99d1a850041c745e23036e83ad39

SHA-256 of the AIXC-MAT-DS-001.zip package: in the file AIXC-MAT-DS-001.zip.sha256, published next to the zip (shasum -a 256 -c AIXC-MAT-DS-001.zip.sha256).