Research — Transmission · Precomputed (draft, unvalidated)

Structure loading walk

Wind pushes on the pole and on the wires; the pole bends, the groundline moments stack up against the capacity, an insulator string swings toward the structure inside its limit arc, and the crossarm and the span set how far the pole can reach. Pick a story and step through it, or switch to free play and snap any loading case. The functions compute values and never judge; ‘exceeds’ and ‘within’ are the exporter's comparison against what was entered.

Story

composite of three bulletin examplesdraft, unvalidated harnessillustrative geometrystring length illustrative

Free play · reads one cell of the exported grid or tables per change

Pole

The 70 ft TP-69 pole uses the Point of Maximum Stress method and different diameters, so it is not a like-for-like swap for the 55 ft poles.

Wind on pole and wires

Horizontal span · pole

Clearance wind condition

Line angle

Horizontal span · swing

Vertical span

Crossarm loading case

Crossarm size · Table G-1 key as printed

Moment arm s

Controls snap to the values the harness was run at; nothing between them is estimated. The pole span, swing span and vertical span are separate steppers because the three bulletin examples use different spans.

Four readings of one loading case · each with the exporter's comparison

End view · across the line, wind from the right

Groundline moments · the stack, the demand and the capacity

String swing · angle from vertical, toward the structure

Spans · the maximum the pole carries, the limits on the vertical span

wind on polewind on wiresunbalanced verticalP-delta (pole deflection)the exporter flags "exceeds"the exporter flags "within"

All nine checks at this step · the controlling row is highlighted

Controlling row (a display choice, not a result): the first row the exporter flags as exceeding, otherwise the row closest to its limit. 'Comparison' is the exporter's flag (demo-logic); the functions compute values and never judge. A panel that is off in a story reads 'not evaluated', never zero.

How the checks read it

Bulletin check · the worked-example values the exporter asserted against the Python results

Every check · the first reading, the change, the last step

Columns are step labels, so a story whose last step is not a fix says so. Where the first, second and last steps coincide, a column reads 'same step'. 'What moved' compares the exporter's exceeds / within flags between steps; it is not a harness result.

Precomputed results:every verdict, required value and margin on this page was computed by the real Python harness at export time and is played back from a data file. The page runs no harness logic and holds no standards tables, and it never interpolates between exported values. Not a live API call. Precomputed by the real utm-agent-harness functions (commit e61dd9d) at export time and played back from a data file. The harness is a DRAFT with no human subject-matter-expert sign-off; nothing here is a compliance determination. The functions COMPUTE values (a moment, a span, a swing angle) and never judge. Where a computed number sits next to a capacity or a limit, the words ‘exceeds’ and ‘within’ are the exporter's own comparison against the value entered in that step (provenance demo-logic), not a harness verdict. The scene is a COMPOSITE of three separate RUS Bulletin 1724E-200 worked examples (the TS-1 55 ft pole, the TH-10 161 kV insulator string and the TS pole-top crossarm); it is not one real structure, the geometry is illustrative, and the harness has no insulator string length so the string is drawn at an illustrative length. Pole classes other than 1 change only the Table F-2 groundline capacity; diameters stay at the TS-1 values. The bulletin gives the wire wind load only at 4 psf; at other pressures the exporter scales it linearly (demo-logic). Swing limits (16.4, 53.2 and 77.7 deg) and conductor tensions are bulletin inputs, not harness outputs. Domain maturity, quoted from the domain page: schema draft, unvalidated; no structural or transmission-line PE has reviewed it; insulator swing, pole capacity, crossarm span and guying are checked against the bulletin's worked examples.Real functions this maps to:max_horizontal_span_ground_line_method, max_horizontal_span_point_of_maximum_stress_method, groundline_moment_capacity_ft_k, groundline_moment_due_to_wind_on_pole, groundline_moment_due_to_wind_on_wires_per_span, deflection_estimate_coefficient, insulator_swing_angle_deg, required_vertical_span_ft, max_vertical_span_ft.Not modeled: guyed poles, H-frames, the iterative deflection-magnifier re-check (the assumed 1.15 is used as given), pole classes with their own taper, any conductor or insulator string other than the three bulletin examples, and whether a given design is acceptable. The pole is drawn with heights to scale and horizontal distances exaggerated; the bending of the pole, the sag of the wire and the length of the string are pictures, not results.See also:Structure loading walk, hands-off walkthrough · Pole groundline moment · Insulator swing vs wind