Transverse Wind Load on Conductor and Pole

Scopeit is the wind on the conductors and on the pole itself, and both land at different heights and become a moment. Wind on a conductor is pressure times projected area, and the projected area of a cylinder is simply its diameter times its length -- so the wind load per foot is the diameter in inches over twelve, times the pressure, and nothing else. THE LENGTH THAT COUNTS IS THE WIND SPAN, half the span on each side of the structure, which is not the same as the ruling span and not the same as the weight span that carries vertical load. Confusing wind span with weight span is the standard error on an angle or a hillside structure, where the two differ substantially. The pole carries its own wind on a tapered projected area, and because that load is distributed over a taper the resultant acts at the trapezoid centroid, h/3 x (B + 2T)/(B + T) above the groundline, a little below mid-height because the pole is wider at the bottom. The force is small next to the conductors but its moment arm is not, and on a tall pole with light conductor it can be the larger term: a 9 psf wind on one ACSR Drake at a 400 ft wind span gives 332 lb at 38 ft, while the 45 ft pole standing 39 ft out of the ground contributes 293 lb at 18.2 ft -- 30% of a 17,955 ft-lb total, which is not a rounding error. Hand that moment to the pole capacity check and the Class 3 pole in that example runs 16% utilized on wind alone, before any conductor tension or angle pull is added. Under ice the conductor diameter grows and so does the wind area, which is why the NESC district cases combine ice AND wind rather than checking them separately -- enter the iced diameter here to build that case, or take the combined resultant from the district loading calculator. This is transverse wind only, on a tangent structure, with a round-shape factor of 1.0 and no gust response factor, height adjustment, or terrain exposure category applied -- all of which the applicable NESC edition and grade of construction require and none of which is here, so this is a screen rather than a design. It does not compute the longitudinal load at a deadend or the transverse component of line tension at an angle structure, both of which can exceed the wind; it does not evaluate the pole's capacity, which is a separate check (the Wood Pole Class and Groundline Moment calculator); and it does not address wind on insulators, hardware, equipment, or a communications underbuild. The applicable NESC edition, the utility's construction standards, and a qualified line designer govern.

Formula or tablewind pressure p = 0.00256 V^2 where a speed is entered; force on a conductor = p x (diameter / 12) x wind span x conductor count; force on a pole = p x its tapered projected area with the resultant at the trapezoid centroid, h/3 x (B + 2T)/(B + T) above the groundline (B groundline, T top diameter); groundline moment = the sum of each force times its height.

Source and editionThe transverse wind load relations by name, with the ASCE 7 velocity-pressure constant 0.00256 -- the same relation the wind-pressure calculator uses. Round shape factor 1.0; NO gust response, height adjustment, or terrain exposure factor is applied, so this is a screen rather than a design. The applicable NESC edition, the utility's construction standards, and a qualified line designer govern.

Free accessPressure times projected area on dimensions the user supplies; no wind map or exposure table is reproduced.

What governsEstimate. AHJ and licensed professional govern.

API field nameswind_pressure_psf, wind_speed_mph, conductor_diameter_in, wind_span_ft, conductor_count, conductor_height_ft, pole_top_diameter_in, pole_groundline_diameter_in, pole_height_above_ground_ft, conductor_force_lb, pole_projected_area_ft2, pole_force_lb, total_force_lb, groundline_moment_ftlb, pole_share_pct

• Wind span, not ruling span or weight span the standard error on an angle or hillside structureoverhead line practice
• No gust, height, or exposure factor a screen, not a grade-of-construction designthe applicable NESC edition
• Transverse only longitudinal deadend loads and angle tension components are not computedoverhead line practice