Bridges · Bearings & joints

Deck expansion joint movement calculator

Joint movement from temperature range, shrinkage and creep shortening over the expansion length; gap at installation.

Standard: AS 5100.2 temperature ranges (inputs) · shrinkage & creep

Inputs in the worked example

The live calculator starts with these values; change any of them and every result, check and diagram updates instantly.

Result	Value	Unit
Temperature movement α L (Tmax − Tmin)	38.88	mm
Shrinkage + creep	40.00	mm
Opening from installation	57.28	mm
Closing from installation	21.60	mm
Total movement range	78.88	mm

Diagram for the worked example

Temperature movement α L (Tmax − Tmin) = 10.8*1E-6*80*1000*(45-0) = 38.88 mm
Shrinkage + creep = (300+200)*1E-6*80*1000 = 40 mm
Opening from installation = 10.8*1E-6*80*1000*(20-0)+40 = 57.28 mm
Closing from installation = 10.8*1E-6*80*1000*(45-20) = 21.6 mm
Total movement range = 57.28+21.6 = 78.88 mm

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For preliminary design and education. Check every result against the current standard and your own engineering judgement before use.