Concrete Strength Development and the Effects of Cold Weather
strength development
Cements are very often used without taking into account that not all concretes with the same 28-day strength, have the same strength development characteristics. These differences can be wisely exploited to enhance efficiencies and sought after characteristics, particularly at early ages, can be optimized upon by the contractor. Examples of some critical aspects of construction are illustrated to give the reader an idea of these differences. Please take note, however, that these figures are by no means absolute and will vary depending on a host of variables.
COLD WEATHER CONCRETING AND THE EFFECT ON STRENGTH DEVELOPMENT
Cold weather can severely affect concrete. The major problems associated with cold weather concrete are:
- Slow or non-setting concrete
- Slow gain in strength
- Frost damage
The correct choice of materials is extremely important however there are measures one can take to avoid problems. For instance, one should always keep in mind of 5 degrees Celsius. The adjoining graph shows that concrete made with a CEMI type cement would only attain 80% of its potential 28 day strength when the average temperature is about 10 degrees Celsius.
COLD WEATHER CONCRETING AND THE EFFECT ON STRENGTH DEVELOPMENT
Cold weather can severely affect concrete. The major problems associated with cold weather concrete are:
- Slow or non-setting concrete
- Slow gain in strength
- Frost damage
The correct choice of materials is extremely important however there are measures one can take to avoid problems. For instance, one should always keep in mind of 5 degrees Celsius. The adjoining graph shows that concrete made with a CEMI type cement would only attain 80% of its potential 28 day strength when the average temperature is about 10 degrees Celsius.
HOW TO MINIMISE PROBLEMS
- Start concreting when temperatures are rising and /or at the appropriate time of day
- Use a higher grade of concrete
- Use correct mixes/cements for each application
- Ask for advice from your suppliers
EFFECT OF TEMPERATURE ON STRENGTH
References
*Fulton’s Concrete Technology 7th Edition. *Concrete Society Technical Report II
