Search results
Results from the WOW.Com Content Network
In engineering, a factor of safety (FoS) or safety factor (SF) expresses how much stronger a system is than it needs to be for an intended load.Safety factors are often calculated using detailed analysis because comprehensive testing is impractical on many projects, such as bridges and buildings, but the structure's ability to carry a load must be determined to a reasonable accuracy.
Permissible stress design is a design philosophy used by mechanical engineers and civil engineers. The civil designer ensures that the stresses developed in a structure due to service loads do not exceed the elastic limit. This limit is usually determined by ensuring that stresses remain within the limits through the use of factors of safety.
Safety engineering is an engineering discipline which assures that engineered systems provide acceptable levels of safety. It is strongly related to industrial engineering/systems engineering, and the subset system safety engineering. Safety engineering assures that a life-critical system behaves as needed, even when components fail.
The safety factor applied to the load will typically ensure that in 95% of times the actual load will be smaller than the design load, while the factor applied to the strength ensures that 95% of times the actual strength will be higher than the design strength. The safety factors for material strength vary depending on the material and the use ...
Load and Resistance Factor Design (LRFD), a Limit States Design implementation, and; Allowable Strength Design (ASD), a method where the nominal strength is divided by a safety factor to determine the allowable strength. This allowable strength is required to equal or exceed the required strength for a set of ASD load combinations.
While engineering, as a rule, factors human safety into the design process, a modern appraisal of specific links to design and workers' safety can be seen in efforts beginning in the 1800s. Trends included the widespread implementation of guards for machinery, controls for elevators, and boiler safety practices.
The factor of safety on ultimate tensile strength is to prevent sudden fracture and collapse, which would result in greater economic loss and possible loss of life. An aircraft wing might be designed with a factor of safety of 1.25 on the yield strength of the wing and a factor of safety of 1.5 on its ultimate strength.
Probabilistic design is a discipline within engineering design. It deals primarily with the consideration and minimization of the effects of random variability upon the performance of an engineering system during the design phase. Typically, these effects studied and optimized are related to quality and reliability.