.. _auto_lsdyna_connection_failure_summary:

*LSDYNA CONNECTION FAILURE TIMELINE*
====================================

Builds a time-bucketed pass/fail summary across LS-DYNA connection branches (swforc, secforc, rbdout, elout). For each connection's force time-history it applies the appropriate failure criterion: Daimler-Chrysler damage-ratio for swforc spotwelds, peak-vs-allowable for secforc sections and elout beams/springs, resultant-vs-allowable for rbdout rigid bodies. The simulation time range is sliced into N buckets and each connection is counted as passed or failed in the bucket where its peak DR (or first failure) lands. Returns per-bucket counts (overall + per-branch) plus a per-branch summary (totals, failed count, peak DR, top failures), driving the BINOUT Explorer's Connections Overview subpane.

When to use
-----------

Tagged: ``binout``, ``buckets``, ``connection``, ``daimler_chrysler``, ``deforc``, ``dc``, ``elout``, ``failure_summary``.

Inputs
------

.. list-table::
   :header-rows: 1
   :widths: 20 20 20 20 20 20

   * - Label
     - ID
     - Type
     - Default
     - Required
     - Description
   * - Simulation
     - simulation_id
     - remote_lookup
     - —
     - 
     - Reference to the LS-DYNA simulation whose binout will be read.
   * - Number of time buckets
     - num_buckets
     - integer
     - 10
     - 
     - Number of equal-duration buckets the simulation time range is sliced into (same idea as the matsum load-path segments). Default 10.
   * - Top-N connections per branch
     - top_n_per_source
     - integer
     - 500
     - 
     - Hard cap on the number of connections evaluated per binout branch, keeping the extractor bounded on models with thousands of welds / sections.
   * - Spotweld — normal capacity Fnf
     - swforc_fnf
     - float
     - 6.0
     - 
     - Daimler-Chrysler normal (tension-only) capacity for swforc spotwelds, in force units consistent with the binout. Set to 0 to skip the normal term.
   * - Spotweld — shear capacity Fsf
     - swforc_fsf
     - float
     - 4.0
     - 
     - Daimler-Chrysler shear capacity for swforc spotwelds. Set to 0 to skip the shear term.
   * - Spotweld — bending capacity Fbf
     - swforc_fbf
     - float
     - 0.0
     - 
     - Daimler-Chrysler bending capacity for swforc spotwelds. Leave 0 when swforc has no moment channel.
   * - Spotweld — EXSN
     - swforc_exsn
     - float
     - 2.0
     - 
     - Daimler-Chrysler normal-term exponent (LS-DYNA EXSN). Default 2.0.
   * - Spotweld — EXSS
     - swforc_exss
     - float
     - 2.0
     - 
     - Daimler-Chrysler shear-term exponent (LS-DYNA EXSS). Default 2.0.
   * - Spotweld — EXSB
     - swforc_exsb
     - float
     - 2.0
     - 
     - Daimler-Chrysler bending-term exponent (LS-DYNA EXSB). Default 2.0.
   * - Section — axial allowable
     - secforc_axial_allow
     - float
     - 50.0
     - 
     - Peak-vs-allowable axial threshold for secforc sections. A section is counted as failed in the bucket where /x_force/ first exceeds this value.
   * - Section — shear allowable
     - secforc_shear_allow
     - float
     - 35.0
     - 
     - Peak-vs-allowable shear threshold for secforc sections (resultant of y_force + z_force).
   * - Rigid body — resultant allowable
     - rbdout_resultant_allow
     - float
     - 100.0
     - 
     - Peak-vs-allowable resultant-force threshold for rbdout rigid bodies (sqrt(x_force^2 + y_force^2 + z_force^2)).
   * - Element (beam/spring) — axial allowable
     - elout_axial_allow
     - float
     - 20.0
     - 
     - Peak-vs-allowable axial threshold for elout beams + springs.
   * - Element (beam/spring) — shear allowable
     - elout_shear_allow
     - float
     - 15.0
     - 
     - Peak-vs-allowable shear threshold for elout beams + springs (resultant of shear_s + shear_t).
   * - Top-N loaded connections per bucket
     - top_loaded_per_bucket
     - integer
     - 5
     - 
     - How many of the highest-force connections to surface per time bucket in the Load-Path subpane. Default 5, max 50.

Outputs
-------

.. list-table::
   :header-rows: 1
   :widths: 20 20 20 20

   * - Label
     - ID
     - Type
     - Description
   * - Per-Bucket Counts
     - buckets
     - dataset
     - Array of {bucket, t_start, t_end, passed, failed, <branch>_passed, <branch>_failed} rows — one per time bucket. Drives the Connections Overview stacked bar.
   * - Per-Branch Summary
     - branch_summary
     - dataset
     - Per-branch {total, failed_count, failed_ids[], peak_dr, peak_dr_at_id, capacities} for swforc / secforc / rbdout / elout.
   * - Top Loaded Per Bucket
     - top_loaded_per_bucket
     - dataset
     - Per-bucket top-N connections by peak resultant force in that bucket (across all branches). Drives the Connection Load-Path subpane: rows = buckets, columns = top connections shown as horizontal force bars.
   * - Meta
     - meta
     - dataset
     - Time range (t_min, t_max), num_buckets, and the effective capacities used.
   * - Summary
     - summary
     - string
     - One-line human-readable summary suitable for log output.

Disciplines
-----------

- cae.postprocessing.extraction
- cae.postprocessing.response
- engineering.crash.dynamics
- engineering.structural.connection_analysis

.. raw:: html

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   <p style="font-size:11px;color:#888">
   Auto-generated from <code>platform</code> schema. Worker id: <code>lsdyna_connection_failure_summary</code>. Schema hash: <code>7d047222bdda</code>. Hand-curated docs in <code>workerexamples/</code> override this page when present.
   </p>