Analysis & loading · Load take-down & combinations
Thermal movement & restraint stress calculator
Free thermal movement, fully restrained stress and force, and movement-joint spacing for an allowable movement.
Standard: Thermal strain α ΔT
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Inputs in the worked example
The live calculator starts with these values; change any of them and every result, check and diagram updates instantly.
| Input | Value | Unit |
|---|---|---|
| Material | Steel (12×10⁻⁶) | |
| Length | 60 | m |
| Temperature change | 40 | °C |
| Area | 6000 | mm² |
| Allowable joint movement | 30 | mm |
Worked example — results
| Result | Value | Unit |
|---|---|---|
| α | 0.000 | /°C |
| E | 200,000 | MPa |
| Free movement α L ΔT | 28.80 | mm |
| Restrained stress E α ΔT | 96.00 | MPa |
| Restrained force | 576.0 | kN |
| Max length between joints | 62.50 | m |
- ✓ Movement within joint allowance
Method, formulas and assumptions
- α = CHOOSE(1,12,10,23)*1E-6 = 1.200e-5 /°C
- E = CHOOSE(1,200000,30000,70000) = 2.000e+5 MPa
- Free movement α L ΔT = 1.200e-5*60*1000*40 = 28.8 mm
- Restrained stress E α ΔT = 2.000e+5*1.200e-5*40 = 96 MPa
- Restrained force = 96*6000/1000 = 576 kN
- Max length between joints = 30/(1.200e-5*40)/1000 = 62.5 m
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For preliminary design and education. Check every result against the current standard and your own engineering judgement before use.