In which types of structures is fatigue most likely to occur?

Fatigue is a critical consideration in the design and analysis of structures subjected to repeated loads and stress cycles. Bridges are particularly susceptible to fatigue due to the dynamic forces they experience from traffic loads, environmental conditions, and other operational impacts over time. As vehicles cross a bridge, they impose varying forces that can induce cyclic loading on the structural members, which may lead to the development of micro-cracks that grow with successive loading cycles.

Bridges often have long spans and are constructed from materials like steel or reinforced concrete that may be sensitive to fatigue under repetitive stress. The effects of fatigue in bridge structures can be significant, leading to structural failures if not properly accounted for in the design and maintenance processes. Engineers must take measures like regular inspections and using materials with good fatigue properties to mitigate these risks effectively.

In contrast, while fatigue can occur in other structures like high-rise offices or residential buildings, the nature and magnitude of loading are generally less frequent or less severe than what bridges experience. Forestry roads, while they may experience some movement from the passage of vehicles, typically do not encounter the same degree of dynamic loading and stress cycles that bridges do, making them less prone to fatigue-related issues. Thus, the environment of a bridge makes it the most likely scenario for experiencing