Contact pressure concept: When a load is transferred through one surface to another surface in direct contact (for example, a pin against a plate), the relevant stress is called what?

Introduction / Context:
Mechanical and structural joints often transmit force through surface contact—pins in lugs, bolts against plates, or rivets in holes. The design must ensure that local surface pressure does not crush the material.

Given Data / Assumptions:

• Load is transferred via surfaces in contact (no significant tension across the interface).
• The stress of interest is localized surface pressure.

Concept / Approach:
The appropriate term for stress due to contact pressure is bearing stress. While it is compressive in nature, calling it simply “compressive stress” is too general and misses the contact-specific meaning. “Working stress” is a design-level stress, not a type, and “shearing stress” acts parallel to area, not normal contact pressure.

Step-by-Step Solution:

Verification / Alternative check:
Design checks for connections compare bearing stress to permissible/limit values and also verify tear-out and net-section tension, confirming that “bearing” is the intended limit state.

Why Other Options Are Wrong:
Tension and shear are different stress modes; “working stress” is not a stress type; generic compression ignores the contact/area definition used in joint design.

Common Pitfalls:
Using nominal fastener area instead of projected bearing area; overlooking edge distance and end distance limits to prevent tear-out.

Final Answer:
Bearing stress