What is the concept of “strong column-weak beam” in ductile detailing?
- AColumn should be designed to be weaker than beams to absorb more energy
- BBeams should be over-reinforced and columns should be under-reinforced
- CBeams should be designed to absorb more energy
- DBeams should be designed to yield before columnsCorrect
Solution
Concept
Strong column weak beam ductile detailing concept
Formula
NONE
Step-by-step solution
1. Seismic design principles promote beam yielding mechanisms before column failure to prevent overall building collapse. 2. Ductile detailing controls member capacities so that flexural yielding is distributed safely. Answer: D
Explanation
The strong column-weak beam concept ensures that plastic hinges develop in flexural beams prior to forming in columns during severe seismic activity. This hierarchy prevents full-story collapse mechanisms while maximizing the building's energy dissipation capacity. Hence, option D is correct.
Why the other options are wrong
A) Designing columns weaker than beams leads to soft-story collapse mechanisms during seismic loading. C) Absorbing energy is a general property of ductile design, but does not describe the specific mechanism in option B.
Shortcut
Strong Column-Weak Beam = Beams yield before columns to prevent total collapse.
Common mistake
Assuming "strong column-weak beam" implies designing columns to yield first or over-reinforcing beams.
Correct answer: D) Beams should be designed to yield before columns