5  6
[1 , 2]

Serviceability describes the conditions under which a structure is considered useful. All structures and systems have serviceability limits which, if exceeded, will cause the structure to become unusable. Serviceability limit state design of structures includes factors such as durability, overall stability, fire resistance, deflection, deformation, displacements, cracking and excessive vibration. [3]

Serviceability failures are “physical failures that impair the serviceability of a system but not its structural integrity.” [3]

Excessive vibrations can cause serviceability failures in many structures. For example, severe winds and/or excess pedestrian traffic may cause an excess amount of vibration on a pedestrian walking bridge making it uncomfortable for people to travel across. Even though the vibrations are not effecting the structural integrity of the bridge, it is not meeting its serviceability requirements. A skyscraper swaying in the wind could also lead to a serviceability failure. The skyscraper may not be in danger of collapsing but the building is rendered unusable because it is causing nausea among its occupants.

Cracking, deformations, and leakages can also cause serviceability failures. A cracked concrete floor that is supposed to be smooth and polished for aesthetic quality is an example of a serviceability failure as it is not meeting the aesthetic requirements of its design. Improper construction of a parking garage and/or minor deformations in its structural members may cause water to pool up on some levels of the parking garage. This becomes a serviceability failure as it is inconvenient for the occupants to access their vehicles. A more extreme example of this type of serviceability failure would be water pooling up on a roof that does not drain properly, creating the possibility for water leakage into the building. This water could drip down onto the gypsum ceiling tiles below causing mold to grow and building occupants to become sick.

Serviceability failures can also occur in mechanical systems. For example, an HVAC system that is not adequately supplying air to one or more rooms or regions of a building, thus causing discomfort among its occupants, is a system experiencing a serviceability failure.

Other Sources:  [3] “Failure Mechanisms in Building Construction.” David H. Nicastro. The American Society of Civil Engineers. Print.

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