Plain Cement Concrete
The mixture of cement, fine aggregate (sand) and coarse aggregate is called plain cement concrete (PCC) .
Main Purpose of PCC
- It is used as a protective layer for the RCC above so that water from the RCC is not absorbed by the earth below.
- Moisture available in soil should not absorbed by R.C.C footings which causes corrosion of reinforcement.
- Provides a base for the concrete and also helps workers to set out the structure above in a easier way. It provides a flat base for upcoming foundation rather than undulated base.
- The effective depth of RCC member is achieved as the form-works can be easily and sturdily fixed.
- As the Grade of comcrete of PCC and Foundation is different it also provide material difference for ground bactrial effect on foundation.
- Act as a cover to reinforced cement concrete i.e. resist corrosion of steel bars in footings.
- Some time it can decrease the stresses to the soil.
PCC remarkably strong in compression, But it is equally remarkably weak in tension. It’s tensile ‘strength’ is approximately one tenth of its compression strength. Hence use of plain concrete as a structural material is limited to situations where significant tensile stresses and strains do not develop.