Dear reader in previous post we have discussed about properties and limits of deleterious substances in aggregate for concrete construction in negligible weathering regions. Now we are discussing about aggregates that have to suffer severe weathering conditions. The location of different weathering regions are shown in the figure below:
The aggregates are designated as below:
1S class aggregates are considered to be used in following conditions
- Floor slab
That is All concrete members are not exposed to weathering and floor slabs essentially interior slab having any types of covering.
2S class aggregates are considered to apply interior floors having no covering.
3S class aggregates are considered to apply in following conditions:
- Foundation walls located above ground
- Retaining wall
- Girders and beams exposed to weather
4S class aggregates are considered to apply in following conditions:
- Bridges decks
- Garage floors
- Exposed porches and floors
- Water-front structures; any types of concrete member that are frequently subjected to wetting
5S class aggregates are considered in architectural concrete exposed to weathering.
Dear reader here we have learnt weathering regions and exposure conditions for severe weathering aggregate. In the next part we will learn about limits of different deleterious substances and corresponding physical properties.