Version: 10.1

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Height

As with selected conductors, Designer attempts to match MMENG values to the selected pole when the Structural Analysis tool is initialized. These values can be changed at any time.

The values in the Height drop-down box are imported from the MMENG_POLEHEIGHTSETDEPTH table. The chosen height is used to calculate the following: Total Wind Moment on Pole, Maximum Resisting Moment, and Total Bending Moment. The height of the pole with its corresponding set depth is used in further clearance calculations on the Clearance tab.

Class

The values in the Class drop-down box are imported from the MMENG_POLECLASSES table. The chosen class is used to calculate the following: Total Wind Moment on Pole, Maximum Resisting Moment, and Total Bending Moment.

Material

The values in the Material drop-down box are imported from the MMENG_WDSPCIESULTFIBERSTRESS table. Designer uses this value along with Height and Class values to display the Maximum Resisting Moment of the pole.

Setting Depth

The Setting Depth text box is initially populated as a result of choosing a pole height. Each pole height record in the MMENG_POLEHEIGHTSETDEPTH table has a corresponding set depth. The value in the Set Depth text box (whether an initial value or an updated value) will be used to calculate Total Bending Moment. Each time a new pole height is chosen the Set Depth text box is refreshed with the corresponding value from the MMENG_ POLEHEIGHTSETDEPTH table.

If the option is checked for "Depth Adjusted For Equipment," Designer will retrieve the corresponding values from the MMENG_SETDEPTHADJUST table for listed devices and add the value to the default setting depth.

Wind Moment on Pole

The Wind Moment on Pole is the bending moment caused by the wind blowing against the surface of the pole. The Wind Moment on Pole uses values from Loading District text box and Conductor Size/Material values from the Conductors Grid to extract the correct Transverse Wind load value from the MMENG_CONDTRANSWINDLOAD table. The result of the following formula is used to display the Wind Moment on Pole:

W_P = (W_P * OCF_W)

(S * M_C(1) * COS(a / 2)) + (S * M_C(2) * COS(a / 2)) + (S * M_C(n) * COS(a / 2)) + …

Where:

W_P = Wind on pole only

a = Angle adjacent spans (from Angle text box)

S = Span length

M_C(1..n) = Transverse wind load on conductor

Maximum Resisting Moment

The Maximum Resisting Moment is the capacity of the pole, based on its size and material, to withstand the loads such as conductor tension and wind, which would tend to break the pole when applied. Using the Height, Class, and Material values, Designer displays the corresponding maximum resisting moment of the pole from the MMENG_WOODPOLERESISMOMENT table.

Total Bending Moment

Total bending moment is defined as the bending moment due to loads from conductor tension, wind on wires/conductors, and wind on the pole itself. If the total bending moment exceeds the total resisting moment of the pole, the Maximum Resisting Moment text box will be highlighted in red. Total Bending Moment on Pole displays the results of the following calculation:

T_B = (Moment due to Conductor Tension) + (Moment due to Conductor Wind Load) + (Moment due to Wind Load on Pole)

T_B = (2 * S(T_C(1-n) * H_C(1-n)) * SIN(a / 2) * OCF_T) + (S * S(M_C(1-n) * H_C(1-n)) * SIN(a / 2) * OCF_W) + (W_P * OCF_W)

Where:

T_B = Total bending moment of pole

T_C(1..n) = Tension of each wire/conductor (1 thru n) from MMENG_CONDTENSION

H_C(1..n) = Height of each wire/conductor attachment (1 thru n)

a = Angle adjacent spans (from Angle text box)

OCF_T = Overcapacity factor for wire/conductor tension load

S = Span length

M_C(1..n) = Transverse wind load of each wire/conductor (1 thru n) from MMENG_CONDTRANSWINDLOAD

OCF_W = Overcapacity factor for wind load

W_P = Wind moment on pole

Total Transverse Load on Pole

The Total Transverse Load on Pole is the resultant force of conductor tension (due to line angle) and conductor wind load applied to the pole. Total Transverse Load on Pole displays the results of the following calculation.

T_T = (Conductor Tension) + (Conductor Wind Load)

T_T = (2 * T_C(1..n)) + (S * M_C(1..n) * COS(a / 2))

Where:

T_T = Total transverse load on pole

T_C(1..n) = Tension of each wire/conductor (1 thru n) from MMENG_CONDTENSION

S = Span length

M_C(1..n) = Transverse wind load of each wire/conductor (1 thru n) from MMENG_CONDTRANSWINDLOAD

a = Angle adjacent spans (from Angle text box)