Equipment Support Resonance

DOE-HDBK-1132-99

Lateral Loads on Partitions . Consider a minimum live load of 5 psf applied

laterally for design of interior walls, permanent partitions, and temporary

partitions that exceed 6 feet in height, except where earthquake or other lateral

loads are greater.

Wind Loads on Building Additions . Consider building additions to be designed

as parts of a totally new building without regard to shielding from the original

building and without regard to lesser wind resistance for which the original

building may have been designed. The original portion of the building may

require strengthening due to an increase in the wind loads.

Equipment Support Resonance . Equipment supports are designed to avoid

1.6.5

resonance resulting from the harmony between the natural frequency of the

structure and the operating frequency of reciprocating or rotating equipment

supported on the structure. Resonance effects may be minimized by designing

equipment isolation supports to reduce the dynamic transmission of the applied

load to as low a level as can be economically achieved.

1.6.6

Creep and Shrinkage . Concrete and masonry structures should be investigated

for stresses and deformations induced by creep and shrinkage.

1.6.7

Environmental Concrete Storage Structures . Environmental concrete storage

structures for containment, treatment, or transmission of water, wastewater, and

low-, intermediate-, and high-level radioactive wastes or other fluids should be

designed and constructed to be watertight, with minimal or no cracks.

ACI addresses this aspect through attention to detailing. Controlling cracks is

described in ACI 224.1R, Causes, Evaluation, and Repair of Cracks in Concrete

Structures; ACI 224.2R, Cracking of Concrete Members in Direct Tension; and

ACI.3R, Joints in Concrete Construction. Some special concrete mixes are

available to minimize cracks. These include shrinkage-compensating concrete

and a special mix using ground granulated blast-furnace slag and fly ash. In

general, these mixes, combined with proper construction techniques, can be

used to control cracks in the concrete.

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