DASLab / 03
Frame & Span
Preliminary depths, loads, moments and column sizes for concrete, steel and timber structures — under Eurocode, ACI / ASCE, Japanese and Egyptian codes.
Experimental tool — evolving and open to suggestions: info@derzawi.com
Suggested depth — RC one-way slab
330 mm
L / 20 on effective depth d (+ cover)
EN 1992-1-1 Table 7.4N, lightly stressed (ρ = 0.5%)
Section & elevation
Loads
Self-weight8.25 kN/m²
Dead load gk9.75 kN/m²
Live load qk2 kN/m²EN 1991-1-1 Table 6.2 recommended values (A, B, C1, C3, D1, F) — check National Annex
Design (factored) area load16.16 kN/m²1.35 G + 1.5 Q (EN 1990 eq. 6.10)
Design (factored) load per m width16.16 kN/m
Actions
Max moment per m width72.7 kN·m
Max shear48.5 kN
Coefficients: simple wL²/8, one end continuous wL²/10, both wL²/12, cantilever wL²/2.
Column below (4 storeys)
Design (factored) axial load2,327 kN
RC column (C30/37 (fck), ρ = 1.5%)375 mm squareEN 1992-1-1 axial: 0.567 fck Ac + 0.87 fyk As, × 0.8 allowance for moments/slenderness
Steel column area (S355, buckling allowance)10,927 mm²
Compare systems — same span and loads
| System | Depth | L / x | Moment |
|---|---|---|---|
| 330 mm | 20 | 72.7 kN·m /m | |
| 290 mm | 24 | 66.7 kN·m /m | |
| 200 mm | 30 | 28.7 kN·m /m | |
| 500 mm | 14 | 300.5 kN·m | |
| 300 mm | 20 | 248.1 kN·m | |
| 600 mm | 12 | 173.9 kN·m | |
| 375 mm | 17 | 173.5 kN·m |
Preliminary sizing only — for early design and feasibility. Not a substitute for calculations by a qualified structural engineer. Wind, snow, seismic, fire, vibration and detailing are not checked.