Structural failure occurs when a structure, such as a building, collapses or physically fails in some similar way. There are many causes of structural failure, both natural and man-made. In some cases, the design or the actual construction of the building may be wrong, while in other cases negligence, congestion, or a natural disaster is the cause. Sensors and mathematical models are employed in building design and maintenance to reduce and monitor the potential for structural failure.
When a building is constructed, the amount of mechanical stress or stress it is likely to experience is priced into the design. Factors of possible stress include the shape and intended use of the building – for example, a high-rise office building is physically different from a multi-level parking garage or a one-story residential home. Each of these buildings will respond to heavy loads, wind, rain and earthquakes in a different way.
Structural failure can occur due to a design flaw if those who designed the building do not pay attention to their location, shape, and application. It can also occur due to negligence or misuse of the building – for example, it overloads its intended capacity with people or the extra weight from items such as machinery. These cases of building collapse are man-made, and can be prevented by modeling the likely load on the building mathematically during the design process and following these guidelines over the life of the building.
Natural disasters and weather phenomena can often be a more challenging threat. Strong wind, fire, the weight of rain or snow and earthquakes can all cause structural failure. Although these factors are expected during design and construction as much as possible, accidents still happen. Unexpected corrosion of a metal frame element due to water seepage can cause the collapse of a structure. Mistakes in concrete mixtures used in building sites can cause cracks and possible failure.
To reduce these dangers, engineers often use sensor systems mounted inside the structure. Devices called accelerometers can measure vibration and are used to measure the function of bridges. Stretch flaps and fiber optics can be used in the detection of stress and strain-induced damage to structures. These and other related sensor devices help engineers predict and prevent possible structural failure.
- The steel frames used in building skyscrapers allow them the flexibility to withstand the force of strong winds.
- Large vertical cracks are often the first sign of structural failure.
- Natural disasters such as earthquakes can contribute to structural failure.