The importance of concrete durability cannot be underestimated.
Concrete durability is simply defined as its ability to resist weathering action and chemical attack, while maintaining the desired engineering properties. Unfortunately, because of the use of improper or inferior materials and mix designs, sub-par construction practices and insufficient curing, a great many concrete structures across the globe are failing to live up to lifespan desires.
How do we measure Concrete durability?
Put simply, it’s difficult. Determining concrete’s longevity and ability to withstand local weathering and use is taxing, but important. Durability of concrete is contingent on where in the world it is being used, how long it is supposed to last and what it’s being used for.
A few questions to consider:
- What are the environmental pressures the concrete structure might face?
- In what application is the structure being used?
- What is the expected lifespan of the structure?
When you are testing for concrete strength, the numbers are quite easily defined and are consistently done so regardless of environmental factors. One area might be looking for different strength capacity than another, but the parameters will stay the same.
Conversely, testing for durability is difficult to define by direct testing methods. However, the relationship between permeability and durability allows the durability of a mix to be determined by testing the permeability of the mix in question.
As has been stated before in numerous articles on this site and through editorials in other publications, the leading cause of early deterioration of concrete deterioration are due to the ingress of water. To have a durable structure, the passage of water through concrete must be reduced. This is also why the best, most reliable concrete waterproofing system is required to secure the proper durability and further, sustainability of concrete structures.
Thus, testing for durability is crucial; however, there are drawbacks and limitations which must be understood. Over the next couple of weeks I will go over three testing methods for durability, beginning with the Absorption Test.