Poisson’s ratio is the ratio of lateral strain to longitudinal strain in a material subjected to loading. Poisson’s ratio varies between 0.1 for high strength concrete and 0.2 for weak mixes. It is normally taken as 0.15 for strength design and 0.2 for serviceability criteria.
V= – (lateral strain)/(longitudinal strain)
What is Poisson’s Ratio of concrete?
1-The value of concrete Poisson’s ratio is possible to vary based on the type of specimen (dry, wet, or saturated), and loading conditions.
2- Comparatively, Poisson’s ratio of concrete under static loads is lower than that of concrete upon which dynamic loads are applied.
3- The concrete Poisson’s ratio under dynamic loads varies mostly between 0.20 to 0.25.
4- By and large, it ranges from 0.1 for high strength concrete to 0.2 for low strength concrete.
5- For the design of concrete structures, the most common value of concrete Poisson’s ratio is taken as 0.2.
6- It is recommended to practice great cautions to ensure that Poisson’s ratio is compatible with values used for shear modulus of elasticity of concrete otherwise serious errors may be encountered.
7- Poisson’s ratio of concrete is constant up to about 70% of strength.
8- It can be computed from the static modulus test.
9- Poisson’s ratio can be determined dynamically from ultrasonic pulse velocity and from the fundamental resonant frequency of longitudinal vibration of the concrete beam.
Poisson’s Ratios for Common Materials
For most common materials the Poisson’s ratio is in the range 0 – 0.5. Typical Poisson’s Ratios for some common materials are indicated below.
Material | Poisson’s Ratio – μ – |
---|---|
Upper limit | 0.5 |
Aluminium | 0.334 |
Aluminium, 6061-T6 | 0.35 |
Aluminium, 2024-T4 | 0.32 |
Beryllium Copper | 0.285 |
Brass, 70-30 | 0.331 |
Brass, cast | 0.357 |
Bronze | 0.34 |
Clay | 0.41 |
Concrete | 0.1 – 0.2 |
Copper | 0.355 |
Cork | 0 |
Glass, Soda | 0.22 |
Glass, Float | 0.2 – 0.27 |
Granite | 0.2 – 0.3 |
Ice | 0.33 |
Inconel | 0.27 – 0.38 |
Iron, Cast – grey | 0.211 |
Iron, Cast | 0.22 – 0.30 |
Iron, Ductile | 0.26 – 0.31 |
Iron, Malleable | 0.271 |
Lead | 0.431 |
Limestone | 0.2 – 0.3 |
Magnesium | 0.35 |
Magnesium Alloy | 0.281 |
Marble | 0.2 – 0.3 |
Molybdenum | 0.307 |
Monel metal | 0.315 |
Nickel Silver | 0.322 |
Nickel Steel | 0.291 |
Polystyrene | 0.34 |
Phosphor Bronze | 0.359 |
Rubber | 0.48 – ~0.5 |
Sand | 0.29 |
Sandy loam | 0.31 |
Sandy clay | 0.37 |
Stainless Steel 18-8 | 0.305 |
Steel, cast | 0.265 |
Steel, Cold-rolled | 0.287 |
Steel, high carbon | 0.295 |
Steel, mild | 0.303 |
Titanium (99.0 Ti) | 0.32 |
Wrought iron | 0.278 |
Z-nickel | 0.36 |
Zinc | 0.331 |