The document compares the Working Stress Method and Limit State Method for structural design. The Working Stress Method is an elastic, stress-based, deterministic design approach where members are designed to remain in the elastic range using allowable stresses. The Limit State Method is a plastic, strain-based, non-deterministic approach where partial safety factors are used and the material is allowed to yield and enter the plastic zone to reach ultimate strength.
2. MachenLink
Working Stress Method Limit State Method
WSM is an elastic design method.
The stress in material is allowed to go beyond the
yield limit and enter into the plastic zone to reach
ultimate strength.
LSM is strain based method.
WSM is deterministic approach.
In this design method, members are designed to
never go beyond their elastic range.
LSM is a plastic design method.
WSM is stress based method.
LSM is non-deterministic method.
Factor safety is used find the allowable stress. Partial Safety factors are used for Design
WSM Vs LSM