Beam classification: which statement best defines a continuous beam in structural analysis?

Introduction / Context:
Structural members are classified by their support and loading conditions. Recognizing a continuous beam is important because its analysis involves continuity conditions and distribution of moments across multiple spans.

Given Data / Assumptions:

• Standard structural engineering terminology.
• Linearly elastic analysis context.

Concept / Approach:
A continuous beam rests on more than two supports, creating multiple spans that are structurally continuous. This continuity alters moment distribution compared to an isolated, simply supported span and generally reduces maximum positive moments within spans while introducing negative moments over supports.

Step-by-Step Solution:

Verification / Alternative check:
Classical methods (Clapeyron’s theorem of three moments, moment distribution, stiffness method) specifically target continuous beams with more than two supports.

Why Other Options Are Wrong:
Fixed at both ends: describes an end condition, not necessarily multi-support continuity.Cantilever (fixed–free): is not continuous.Overhanging beams extend beyond a support but may still have only two supports.Simply supported at two ends: by definition, not continuous.

Common Pitfalls:
Confusing overhanging beams with continuous beams; overhangs are still usually two-support systems with extensions beyond a support.

Final Answer:

supported on more than two supports