thermal expansion

The amount of thermal expansion and contraction of concrete varies with factors such as type and amount of aggregate, richness of mixture, water-cement ratio, temperature range, concrete age, and degree of saturation of concrete. A typical value of thermal expansion and contraction of concrete is on the order of 10 millionths per degree Celsius, that is, very near the same as that for steel. If an unrestrained slab or wall 30 meters long has a temperature variation from summer to winter of 38 degrees Celsius, the total thermal movement might be about 1.5 to 1.8 centimetres. Movements occur at the exposed surface of the concrete, which cools off more quickly, before they occur in the interior of the section, leading frequently to additional warping or curling effects. Observations of buildings in service indicate the total movement is usually less than half of that which might be anticipated by combining the contraction due to temperature drop with the shrinkage. This is due to restraining effects of the reinforcing steel and restraining effects of columns, walls, and foundations.
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The coefficient of thermal expansion (CTE)
Continuously reinforced concrete pavements (CRCPs)
In order to prevent CRCP distresses, the Texas Department of Transportation (TxDOT) has limited the CTE of CRCP concrete to a maximum of 5.5 x10-6 strain/oF (9.9 x10-6 strain/oC).
Subject(s)
Coefficient of thermal expansion
CTE
Concrete
Poromechanics
CTE optimization
Internal water pressure
AASHTO
TxDOT
CRCP
Concrete pavement
MEPDG

COEFFICIENT OF THERMAL EXPANSION
PER DEGREE CENTIGRADE
Cement Concrete - Quartzite  1.2 to 1.3 x 10^-5
Cement Concrete - Sand Stone  0.9 to 1.2 x 10^-5
Cement Concrete - Granite  0.7 to 0.95 x 10^-5
Cement Concrete - Basalt  0.8 to 0.95 x 10^-5
Cement Concrete - Lime stone  0.6 to 0.90 x 10^-5
Aluminum  .0000230
Brass  .0000188
Bricks/Brick Work  .0000055
Cement  .0000144
Glass  .0000081
Granite  .0000085
Iron  .0000110
Lead  .0000290
Marble  .0000110
Sand Stone  .0000125
Steel  .0000120
R.C.C.  .0000117
Tin  .0000125
Zinc  .0000325
Wood  .0000110

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