Piercefield Corporation

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ImageSouthern Pine lumber has been used since Colonial times. Favorable growing conditions and wise forest management assure a continuous supply, and highly efficient manufacturing delivers quality Southern Pine products. 

 

 

 

 
With the proper loading distribution dimensional lumber could be the most cost effective option for your application. Our designers will be happy to disscuss which method would best suit your needs. For more information examine the Southern Pine.

 

 

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Southern Pine Span Tables for Joists & Rafters

 

 

 

Loading Distribution

Span - is the distance from face to face of supports (i.e., clear opening), plus one half the required bearing length at each end. The headers and beam sizes provided in these tables were computed using standard engineering design equations for beams with uniform loads applied. Four design condition were considered:

 

  1. Bending
  2. Deflection
  3. Compression perpendicular-to-grain
  4. Shear parallel-to-grain (horizontal shear)

Load Duration - Wood has the ability to carry substantially greater maximum loads for short durations than for long durations. Tabulated design values apply to normal loading conditions, and may be multiplied by a load duration factor, Cd, permitted by established engineering deign criteria and building code regulations. This factor is covered in detail in the NDS, and summarized in the Southern Pine Use Guide available from SPC.

Design Load - is the load to which a particular section of the structure has been designed. We will be looking at two types of design loads - roof loads and floor loads. Each design loads has two components - dead and live load

Dead Load - is the vertical load due to the weight of all permanent structural and nonstructural components of a building, such as walls floors, roofs and fixed service equipment.


Live load - is the load superimposed temporarily by use and occupancy such as people, wind and snow loads.

DL + LL = TL
The dead load (DL) plus the live load (LL) equals the total design load (TL)Tabulated bending and shear design values were increased for load duration (i.e., Fv x Cd) as follows:

Load Duration Cd

Ten years
(occupancy load)
----- 1.00

Two months
(snow load)
----- 1.15

Seven days
(construction load)
------1.25

Last Updated ( Monday, 06 August 2007 )
 
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