Concrete is a composite with properties that change with time. During service, the quality of concrete provided by initial curing can be improved by subsequent wetting as in the cases of foundations or water retaining structures. However, concrete can also deteriorate with time due to physical and chemical attacks. Structures are often removed when they become unsafe or uneconomical.
Lack of durability has become a major concern in construction for the past 20 to 30 years. In some developed countries, it is not uncommon to find large amount of resources, such as 30 to 50% of total infrastructure budget, applied to repair and maintenance of existing structures. As a result, many government and private developers are looking into lifecycle costs rather than first cost of construction. Durability of concrete depends on many factors including its physical and chemical properties, the service environment and design life. As such, durability is not a fundamental property.
In the Concrete lab, test on building materials is performed such as:-
1)Standard Test Method for Density, Specific Gravity and Absorption of Fine Aggregate
2) Standard Test Method for time of setting of Hydraulic cement by Vicat Needle
3) Standard test method for fineness of Portland cement
4) Standard test method for compressive strength of hydraulic cement mortars
5) Standard test method for slump of hydraulic cement concrete
6) Gradation of Concrete Coarse Aggregate
7) Determination of Fineness of Cement