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tan
AASHTO references are in
Standard values are in
blue
Checks and results are in
yellow
Signals.
(3-second gust)
[ref. AASHTO, Figure 3-2]
Number of sections used to create the pole (see Elevation drawing above)
Maximum Fill height measured from natural ground
Corner Radius of Pole Section: for hexdecagonal members, a Ratio of the corner radius to radius of inscribed circle is required
[ref. AASHTO, Table 3-6]
for round sections, enter 20 or higher
(no less than 8)
(flat to flat)
must be an even number
Luminaire properties are used to calculate the axial force, wind load moment, and drag due to the luminaire.
[ref. AASHTO, Table 3-6]
Up to five applied forces (point loads) can act on the structure due to arms, panels, or other attachments on the structure.
[ref. AASHTO, 3.8.4]
K
create matrix to plot pole shape
Wind Importance Factor
For 50 years recurrence interval :
Gust Effect Factor
Unmodified wind pressure (Kz, Ir and G will be included later)
Axial forces due to luminaire dead load and shear forces due to wind load on the luminaire are calculated in the section.
Pole forces are assumed to act at the CG of each segment (50 is the default) and a sectional analysis is performed at the end of each segment.
section number
the following routines will add one wall thickness per section of height to the tube radius beginning with the second section to account for the increased radius due to each slip joint
Note that the extra 6 in is to account for galvanization thickness.
section zero is the top of the pole with the 'y' distance measured from the base
section properties at each section
weight per segment (bare pole)
add
Each segment on the pole may have a different height and exposure factor K
for hexdecagonal members, a Ratio of the corner radius to radius of inscribed circle is required
[ref. AASHTO, Table 3-6]
Dodecagonal rs requirement check
Velocity conversion factor
[ref. AASHTO, Table 3-4]
(for recurrence interval = 50 years)
Coefficient of Drag
[ref. AASHTO, Table 3-6]
[ref. AASHTO, Table 3-1]
Pole Moments and Shears at sech section
Note:
All forces, (applied, luminaire, and pole) are combined and calculated per segment.
Torque for concentrically mounted light sources shall be calculated as the wind loads multiplied by 0.15 times their overall width.
[ref. AASHTO, fig 3-4]
[ref. AASHTO, Appendix B Table B-2]
Maximum bending stresses are based on the principal stresses acting on the section (formula varies depending on the cross section shape).
the bending stress is calculated based on of the number of sides
[ref. AASHTO, Appendix B (Table B-2)]
[ref. AASHTO, Appendix B (Table B-2)]
Maximum shear stresses are the resultant stresses acting on the section (formula varies depending on the shape of the cross section).
torsional shear
total shear
The formula varies depending on the slenderness b/t.
allowable polygonal tube bending stresses
allowable round tube bending stresses
[ref. AASHTO, Table 5-3]
[ref. AASHTO, Table 5-6]
Formula varies depending on the slenderness
[ref. AASHTO, 5.11.1 & 5.11.2]
allowable round and polygonal tube shear stresses
The coefficient of amplification is used to estimate the second order
The combined stress ratio of each pole section must be less than one.
separating out each component
from the curvature results at each section (M/EI), curve fit a fourth degree polynomial, then integrate twice to get deflections.
To get a function for curvature (M/EI), set the y axis as curvature
degree of polynomial to fit
number of data points
polynomial coefficients
polynomial function
now integrate the curvature function twice to get deflections.
evaluates to
compare stresses at the base
graph the calculated deflected shape
[ref. AASHTO, Table 5-4]
[ref. AASHTO, Eq. 5-23]
(Assuming 5 threads per inch.)
[ref. AASHTO, 5.17.4]
shear stress per bolt
tensile stress per bolt, neglecting axial loads (conservative)
Allowable shear stress
[ref. AASHTO, Eq. 5-22]
Allowable tension stress
[ref. AASHTO, Eq. 5-21]
Design plate to resist tensile capacity of the critical corner bolt.
Base Plate Performance Ratio
Use the AISC LRFD Code
round up to the next 1/16th inch
round up to the next 1/16th inch
[ref. AASHTO, 11.6]
Design by Fatigue Category
Fatigue Importance factor
[ref. AASHTO, Table 11-1]
Since the the pole is tapered, only natural wind Gust fatigue is included.
[ref. AASHTO, 11.7.3]
Note:
Axial forces due to luminaire dead load and shear forces due to wind load on the luminaire are calculated in the section.
All forces, (applied, luminaire, and pole) are combined and calculated per segment.
Torque for concentrically mounted light sources shall be calculated as the wind loads multiplied by 0.15 times their overall width.
[ref. AASHTO, fig 3-4]
[ref. AASHTO, Appendix B Table B-2]
Maximum bending stresses are based on the principal stresses acting on the section (formula varies depending on the cross section shape).
the bending stress is calculated based on of the number of sides
[ref. AASHTO, Appendix B (Table B-2)]
Applied Fatigue Loads:
Fatigue Weld Stress:
Handhole Ring Fatigue Stress:
Stress Category = B
[ref. AASHTO, Table 11-2]
[ref. AASHTO, Table 11-3]
Stress Category = E'
[ref. AASHTO, Table 11-2]
[ref. AASHTO, Table 11-3]
[ref. AASHTO, 13.6]
distance from top of shaft to soil
Ground Slope:
Vertical=1
[ref. AASHTO, Eq. C 13-8]
[ref. AASHTO, Eq. C 13-7]
Shaft Performance Ratio in sandy soil
Shaft Performance Ratio in clay soil
Length increase to account for sloped ground.
Shaft Performance Ratio
Design Drilled Shaft for Axial and Bending Forces
percent of steel area to
Bar Size Designation
Tie Bar Size Designation
Common English Rebar Matrix
Area (in2)
Weight (lbf/ft)
Diameter (in)
transition of phi factor from column to beam for round section
Find index that is closest to pure bending (P=0)
Plot the column interaction diagram and the two points considered
Calculate the total length of each pole section
Calculate the base and tip diameter of each pole section (rounded to the next eighth of an inch)
calculate circle coordinates for shaft, rebar, plate and bolt group
Pole Combined Stress Ratio
(15% max.)
Secondary Stress by different methods
Combined Stress Ratio
Shaft Performance Ratio
distance from top of shaft to soil