A support is said to be non-yielding if:
Try it first: pick an option, then read the explanation.
Asked in SSC JE 01/03/2017 (Evening)
Detailed Explanation
Disputed key: the book's key gives (d) "zero slope at the support". That is the condition of a fixed (built-in) support, not the meaning of "non-yielding". In structural analysis, a non-yielding (rigid, unyielding) support is one that does not settle or deflect under load.
Why “it can take any amount of reaction” Is Correct
A support that does not yield can develop whatever reaction is needed without moving, so its deflection stays zero. This is the assumption behind the standard support conditions (y = 0) used in deflection and indeterminate analysis. A yielding support, in contrast, sinks in proportion to the reaction (like a spring or a flexible cross-beam). We give (a) and flag the book's (d).
| Support term | Meaning | Condition used in analysis |
|---|---|---|
| Non-yielding (rigid) | Does not settle or move, whatever the reaction | y = 0 |
| Yielding (elastic / sinking) | Moves in proportion to the reaction (spring, flexible beam) | y = R/k |
| Fixed (built-in) | No translation and no rotation | y = 0 and dy/dx = 0 |
| Simple (pin / roller) | No vertical translation, free rotation | y = 0, M = 0 |
Why the Other Options Are Wrong
- B. it is frictionless: Frictionless describes a roller's horizontal freedom, not whether it yields vertically.
- C. it holds the beam firmly: "Holds the beam firmly" is vague; it suggests fixity rather than non-yielding.
- D. the beam has zero slope at the support: Zero slope describes a fixed support (book's key) — a pinned support can be non-yielding yet allow rotation.
Key Point
Non-yielding support = rigid support that does not sink, whatever the reaction (y = 0). Zero slope means fixed.
Key Concepts for Students
- Settlement of supports induces extra moments in indeterminate beams.
- A flexible prop gives a smaller reaction than a rigid prop.
- Book key (d) is flagged as disputed on this page.
Practice more: this is question 22 in Slope and Deflection MCQs – Part 2. Try the whole set and check every answer instantly.