Short column criterion for rectangular RCC columns A column is considered short if both slenderness ratios are less than:

Introduction:
Slenderness ratio governs whether a column behaves predominantly in compression (short) or requires additional allowance for buckling (slender). Recognizing the limit ensures the correct interaction curves and capacity reduction factors are used.

Given Data / Assumptions:

• Rectangular reinforced concrete column.
• Slenderness ratios considered about both principal axes.
• Limit value to classify the member as short.

Concept / Approach:
For RCC, slenderness ratio is defined as l_e / D for each axis (effective length divided by respective lateral dimension). If both ratios are less than a threshold (commonly 12), the column is classified as short, and axial load with small eccentricity design is applicable without slenderness amplification.

Step-by-Step Solution:
1) Compute l_ex / D_x and l_ey / D_y.2) Compare each with 12.3) If both are < 12, treat the column as short.4) Otherwise, apply slender column design including additional moments from second-order effects.

Verification / Alternative check:
Design examples and charts demarcate short vs slender at about 12 for RCC; steel columns use different limits.

Why Other Options Are Wrong:
8 and 10 are overly restrictive; 16 is too lax and may allow significant buckling effects to go unchecked.

Common Pitfalls:
Using overall instead of effective length; checking only one axis while neglecting the other.

Final Answer:
12