# STRAIN CALCULATION WITH STRAIN ROSETTE MEASUREMENT

Following strain rosette calculator is used to calculate strain results of εx, εy, and γxy with the measurement results of strain rosette (ε1, ε2, ε3) . Calculation of rosette types with different angle setups  (e.g. 45° - Rectangular Rosettes and 60° - Delta Rosette) can be done by simply changing angles in calculator. The formulas used for the calculations are given below.

 Parameter Formula Measured strain-1 (ε1) εx(cosθ1)2+εy(sinθ1)2+γxysinθ1cosθ1 Measured strain-2 (ε2) εx(cosθ2)2+εy(sinθ2)2+γxysinθ2cosθ2 Measured strain-3 (ε3) εx(cosθ3)2+εy(sinθ3)2+γxysinθ3cosθ3

### Strain Rosette Calculator: INPUT PARAMETERS Parameter Value Unit Measured strain-1 (ε1) μm/m (μin/in) Measured strain-2 (ε2) Measured strain-3 (ε3) Line-1 angle wrt x-axis (θ1) deg Line-2 angle wrt x-axis (θ2) Line-3 angle wrt x-axis (θ3)

Note: Use dot "." as decimal separator.

 RESULTS Parameter Value Unit Normal strain in x-direction (εx) --- μm/m (μin/in) Normal strain in y-direction (εy) --- Shear strain in xy-direction (γxy) ---

### Definitions:

Normal Strain: The ratio of length change to original length of the material. ε=σ/E

Strain Gage: An electrical measurement device to measure strain.

Strain Rosette: Strain gauge arrangement to measure three normal strains (ε1, ε2, ε3).

Shear Strain: The angular distortion on element caused by shear stress. γ=τ/G.

### Examples

 Link Usage Principal Stress Calculation Example with Strain Gauge Rosette Measurement An example about the calculation of normal and shear strain and principal stresses on a machine component with the usage of strain results which have been measured with 45° Rosette.

### Supplements:

 Link Usage Plane Stress Calculation with Strain Rosette Results Calculates principal stresses of plane stress state with the usage of strain gage rosette measurement results.

### Reference:

• Beer.F.P. , Johnston.E.R. (1992). Mechanics of Materials , 2nd edition. McGraw-Hill