C45/55 vs C90/105

C90/105 is 1.2 times as stiff as C45/55. Their densities are about the same. Per unit mass C90/105 is 1.2 times as stiff. Strength: f_ck = 45 MPa for C45/55, f_ck = 90 MPa for C90/105.

Side by side

ratio = C90/105 / C45/55 · log scale
Property C45/55 C90/105UnitRatio¼×1×4×
E Young's modulus 36 44 GPa 1.22×
G Shear modulus 15 18.33 GPa 1.22×
ν Poisson's ratio 0.2 0.2 – 1×
ρ Density 2447 2447 kg/m³ 1×
γ Weight density 24 24 kN/m³ 1×
α Coefficient of thermal expansion 10 10 10⁻⁶/K 1×
f_ck Characteristic cylinder strength 45 90 MPa 2×
f_ck,cube Characteristic cube strength 55 105 MPa 1.91×
f_cm Mean cylinder strength 53 98 MPa 1.85×
f_ctm Mean tensile strength 3.8 5 MPa 1.32×
f_ctk,0.05 Tensile strength, 5 % fractile 2.7 3.5 MPa 1.3×
f_ctk,0.95 Tensile strength, 95 % fractile 4.9 6.6 MPa 1.35×
ε_c1 Strain at peak stress 2.4 2.8 ‰ 1.17×
ε_cu1 Ultimate strain 3.5 2.8 ‰ 0.8×
ε_c2 Strain at peak, parabola–rectangle 2 2.6 ‰ 1.3×
ε_cu2 Ultimate strain, parabola–rectangle 3.5 2.6 ‰ 0.743×
n Exponent, parabola–rectangle 2 1.4 – 0.7×
ε_c3 Strain at peak, bilinear 1.75 2.3 ‰ 1.31×
ε_cu3 Ultimate strain, bilinear 3.5 2.6 ‰ 0.743×
E/ρ Specific stiffness E/ρ · derived 14.71 17.98 MJ/kg 1.22×
c₀ Bar wave speed √(E/ρ) · derived 3835 4240 m/s 1.11×
f/ρ Specific strength f/ρ · derived 18.39 36.78 kJ/kg 2×

Values at the first thickness band or product form of each material (EN 1992-1-1; EN 1992-1-1). A minimum and a characteristic value are not the same kind of number — read the ratio as a guide. Each material's page lists every band and every source.