Engineering Notes

ENGINEERING NOTES

UPRIGHT CAPACITY CHARTS

UNARCO designs conform to the latest Rack Manufacturers Institute (RMI) specifications and American Iron & Steel Institute (AISI) Cold Formed Steel Design Manual. Frame capacities are based on maximum unsupported length which is the measurement of the distance between the floor and the top of the first beam or the maximum spacing between beams — whichever governs. Contact the Springfield Office for the following conditions:

a.) Any application where the frame load exceeds 31,000 pounds. These situations may need heavier than standard frame bracing.

b.) Any application that requires seismic design where the ground acceleration is greater than 0.05g or if Ss exceeds 25%g in IBC areas.

c.) Configurations that require a frame deeper than 60″ or taller than 480″.

d.) Applications that involve support of platforms or catwalks or any application other than standard pallet rack.

e.) Single bays of rack.

f.) Any condition which creates uncertainty as to the proper use of these tables. Table values are column capacities based on gravity loading only. The table values are based on the assumption that the rack bracing is adequate (none of the above conditions apply), and all other aspects of the rack have been properly designed. All values are for undamaged racks.

All values in these tables assume that each column carries half of the frame load; the table values are expressed in pounds per frame. These values are based on gravity loading only that is purely axial. Any condition where the axial load is accompanied by moment, the axial load capacity will be less. This will occur for non-symmetrical loading conditions. The capacities also assume the base plates and the bracing are of adequate strength and that all other parts of the rack have been properly designed. All values are for undamaged racks that are installed plumb. It is the rack user’s responsibility to properly maintain the racks to ensure that the carrying capacity of the racks is not reduced by damage and that changes to the rack configuration do not cause unsafe conditions.

BEAM CAPACITY NOTES:

All capacities are expressed in pounds per pair of beams. Only gravity loading and the RMI required impact have been considered.

  • All values are based on a uniformly distributed load (i.e. each beam carries 50% of the load) and assume proper installation and no beam damage.
  • The deflection limit for all beams is the length divided by 180.
  • Roll-formed beams that are longer than 150” require lateral ties.
  • Structural beams that are longer than 108″ can require lateral ties.
  • Values in the table are for the beam bending only.
  • Please consult Springfield , Engineering for any shelf load over 10,000 lbs.
  • Capacities include 12.5% impact for two pallets side by side. For a three-pallet-wide shelf, the values should be multiplied by 0.95. For one pallet per shelf, the values should be multiplied by 0.90.
  • Capacity chart is based on current RMI specifications.

UNARCO rack designs conform to the latest Rack Manufacturers Institute (RMI) specifications and American Iron and Steel Institute (AISI) Cold Formed Steel Design Manual.