CP2737

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Re-written Strength Loading Code (CP2737)
Bob Peters RCP Engineering
January 9, 2007 Orlando Towers, Poles
Conductors Meeting
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Intent of CP2737

• Incorporate ASCE 7 methodology into NESC
• Upgrade distribution design (Grade C) to include
  extreme wind and wind and ice loads
• Consistent Overload and Strength Factors
• Specify Construction and Maintenance Loads

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IntegratedRe-Write of Strength Loading

• Proposed as an Alternate Method for NESC 2007

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IntegratedRe-Write of Strength Loading

• Total of 77 comments
• Comments mostly negative
• Elimination of 60 ft. exemption
• Complexity (wind pressure calculation
• procedures, )
• Major impact on distribution pole design

5
Portions of CP2737 now in 2007 NESC

• ASCE 7 50-year Combined Ice and Wind Map and wind
  pressure
• (New Rule 250D, NESC 2007)
• Consistent Overload and Strength Factors apply
  for loads in 250C and 250D

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Portions of CP2737 not in 2007 NESC

• Removal of light, medium, and heavy loading which
  include arbitrary overload and strength factors.
• Incorporation of distribution structures (Grade
  C) under 60 feet into rational design approach of
  ASCE 7.

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Loading Districts
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Resubmit Change Proposal forNESC 2012 ?

• Possible resubmittal (?)
• Three loading conditions (light, medium or heavy
  high wind and ice and wind combo) are very
  complicated and confusing
• Distribution design approach should be same as
  transmission.
• Need to be more specific for construction and
  maintenance loads.