C55/67 vs C70/85

C70/85 is 1.1 times as stiff as C55/67. Their densities are about the same. Per unit mass C70/85 is 1.1 times as stiff. Strength: f_ck = 55 MPa for C55/67, f_ck = 70 MPa for C70/85.

C55/67 EN 1992-1-1 C70/85 EN 1992-1-1

Side by side

ratio = C70/85 / C55/67 · log scale

Property	C55/67	C70/85	Unit	Ratio
E Young's modulus	38	41	GPa	1.08×
G Shear modulus	15.83	17.08	GPa	1.08×
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	55	70	MPa	1.27×
f_ck,cube Characteristic cube strength	67	85	MPa	1.27×
f_cm Mean cylinder strength	63	78	MPa	1.24×
f_ctm Mean tensile strength	4.2	4.6	MPa	1.1×
f_ctk,0.05 Tensile strength, 5 % fractile	3	3.2	MPa	1.07×
f_ctk,0.95 Tensile strength, 95 % fractile	5.5	6	MPa	1.09×
ε_c1 Strain at peak stress	2.5	2.7	‰	1.08×
ε_cu1 Ultimate strain	3.2	2.8	‰	0.875×
ε_c2 Strain at peak, parabola–rectangle	2.2	2.4	‰	1.09×
ε_cu2 Ultimate strain, parabola–rectangle	3.1	2.7	‰	0.871×
n Exponent, parabola–rectangle	1.75	1.45	–	0.829×
ε_c3 Strain at peak, bilinear	1.8	2	‰	1.11×
ε_cu3 Ultimate strain, bilinear	3.1	2.7	‰	0.871×
E/ρ Specific stiffness E/ρ · derived	15.53	16.75	MJ/kg	1.08×
c₀ Bar wave speed √(E/ρ) · derived	3940	4093	m/s	1.04×
f/ρ Specific strength f/ρ · derived	22.47	28.6	kJ/kg	1.27×

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.