TEMPERATURE GRADIENT IN CONCRETE ITS EFFECTS AND HOW TO REDUCE IT...

TEMPERATURE   GRADIENT   ...

Temperature gradient may be defined as ratio between difference of temperature between two points in concrete to the distance between these to points.

Generally during chemical reaction between cement and water heat which is produce during reaction is travel towards center of structure due to which temperature gradient occurs and causing stress , stress which is produce in concrete is more than flexural stress (flexural stress = 0.7(fck)1/2  of concrete 

due to which cracks are develops in concrete.

EFFECTS ...

Due to variation of temperature, stress are produce in concrete which leads to cracks of concrete, when this stress extends the limit of concrete stress and also causing corrosion of steel and make structure week.

HOW TO CONTROL ...

1) By using ice water to produce concrete to control heat.

2) By using pozzalanic  materials such as flyash , microsilica, alcofine, GGBFS in concrete.

3) By controlling temperature of aggregates by sparkling of water in stockyard.

4) By providing shades during concreting in day.

5) By early curing of concrete.