Structural collapse

Structural integrity and failure is an aspect of engineering which deals with the ability of a structure to support a designed load (weight, force, etc...) without breaking, and includes the study of past structural failures in order to prevent failures in future designs.

Structural integrity is the ability of an item—either a structural component or a structure consisting of many components—to hold together under a load, including its own weight, without breaking or deforming excessively. It assures that the construction will perform its designed function during reasonable use, for as long as its intended life span. Items are constructed with structural integrity to prevent catastrophic failure, which can result in injuries, severe damage, death, and/or monetary losses.

Structural failure refers to the loss of structural integrity, or the loss of load -carrying capacity in either a structural component, or the structure itself. Structural failure is initiated when a material is stressed beyond its strength limit, causing fracture or excessive deformations; one limit state that must be accounted for in structural design is ultimate failure strength. In a well- designed system, a localized failure should not cause immediate or even progressive collapse of the entire structure.

Structural integrity is the ability of a structure to withstand its intended loading without failing due to fracture, deformation, or fatigue.  It is a concept often used in engineering to produce items that will serve their designed purposes and remain functional for a desired service life .

To construct an item with structural integrity, an engineer must first consider a material’s mechanical properties, such as toughness, strength, weight, hardness, and elasticity, and then determine the size and shape necessary for the material to withstand the desired load for a long life. Since members can neither break nor bend excessively, they must be both stiff and tough.  A very stiff material may resist bending, but unless it is sufficiently tough, it may have to be very large to support a load without breaking.  On the other hand, a highly elastic material will bend under a load even if its high toughness prevents fracture.

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