Home / Simulations / Rapid Sizing Drill
🧮 Rapid Sizing Drill
A random span or story count, one question: what size would you guess? Type your estimate, check it against the standard rule-of-thumb range, then try another — no score to chase, just building the engineer's most underrated skill: knowing roughly the right answer before you open a calculator.
—
Loading…
mm
0
Attempted
0
Within range
These are standard, widely-taught preliminary sizing
rules-of-thumb (span-to-depth ratios etc.) — useful for a first guess before real
calculation, never a substitute for it. Real member sizes depend on loads, material
grade, code requirements, and span continuity; always verify with the appropriate
calculator (see this platform's Reinforced Concrete / Steel Design categories) before
using any number for actual design.
Rules of thumb used
RC beamDepth h ≈ L/12 to L/10 for a simply-supported reinforced concrete beam — a widely-cited preliminary sizing range.
RC slabThickness h ≈ L/32 to L/28 for a one-way reinforced concrete slab.
Steel beamDepth h ≈ L/20 for a typical steel floor beam — a common starting estimate.
Building periodT1 ≈ 0.1·N (N = number of stories) — the classic rough estimate for a building's fundamental period, consistent with the ASCE 7 / TBDY approximate-period formulas at low-to-mid rise.