{
  "schema": "support-layout-phases/v1",
  "phases": [
    {
      "id": 1,
      "tasks": [
        "supplier design-frequency basis",
        "route/line spacing",
        "corners/intersections/elevation-change points",
        "valve/concentrated weight support",
        "common piers if practical"
      ]
    },
    {
      "id": 2,
      "tasks": [
        "evaluate cantilever geometry",
        "hold-down near headers",
        "dimension remaining straight runs",
        "preserve thermal freedoms"
      ]
    },
    {
      "id": 3,
      "tasks": [
        "smallest selected line first",
        "add simple intermediate rests",
        "extend common piers without equating freedom sets",
        "selected procedure offsets adjacent intermediate spans at least3in; not universal"
      ]
    }
  ],
  "boundary_models": [
    {
      "id": "two_ended",
      "method": "two outer hold-downs plus intermediate simple rest; tabulated L is simple-rest to right-hand hold-down subspan; left subspan L minus6in or more; overall outer interval not labelledL"
    },
    {
      "id": "one_ended",
      "method": "hold-down to simple support interval; separate table"
    }
  ],
  "hold_down": "limits uplift as defined; not automatically axial anchor or fixed rotation",
  "unknown_cells": "source damaged size30,L22ft cell not used or treated as zero",
  "dimensions_and_frequency": "none encoded in authored layout",
  "acceptance": "supplier/system dynamic, thermal, actual support stiffness and structural reaction evaluation separate"
}