Structural load

Particular mechanical structures—such as aircraft, satellites, rockets, space stations, ships, and submarines—are subject to their own particular structural loads and actions.

[3] Engineers often evaluate structural loads based upon published regulations, contracts, or specifications.

These loads come in many different forms, such as people, equipment, vehicles, wind, rain, snow, earthquakes, the building materials themselves, etc.

In some cases structures may be subject to other loads, such as those due to earthquakes or pressures from retained material.

The term can refer to a laboratory test method or to the normal usage of a material or structure.

Building codes require that structures be designed and built to safely resist all actions that they are likely to face during their service life, while remaining fit for use.

They are developed to help achieve the desired level of reliability of a structure[6] based on probabilistic studies that take into account the load's originating cause, recurrence, distribution, and static or dynamic nature.

Roof and floor live loads are produced during maintenance by workers, equipment and materials, and during the life of the structure by movable objects, such as planters and people.

Dead loads have small load factors, such as 1.2, because weight is mostly known and accounted for, such as structural members, architectural elements and finishes, large pieces of mechanical, electrical and plumbing (MEP) equipment, and for buildings, it's common to include a Super Imposed Dead Load (SIDL) of around 5 pounds per square foot (psf) accounting for miscellaneous weight such as bolts and other fasteners, cabling, and various fixtures or small architectural elements.

Live loads, on the other hand, can be furniture, moveable equipment, or the people themselves, and may increase beyond normal or expected amounts in some situations, so a larger factor of 1.6 attempts to quantify this extra variability.

[11] Gust loads are determined statistically and are provided by an agency such as the Federal Aviation Administration.

Crash loads are loosely bounded by the ability of structures to survive the deceleration of a major ground impact.