Porosity can be defined as the total volume of the overall volume of the pores larger than the gel pores, expressed as a percentage of the overall volume of the cement paste. The effects of pores smaller than 20mm in diameter were found to be negligible.
Porosity Factors Affecting Concrete Strength
The strength of concrete is fundamentally a function of the volume of voids in it. The strength of concrete is influenced by
- The volume of all the voids in the concrete
- Entrapped Air
- Capillary Pores
- Gel Pores
- Entrained Air
Relationship between Compressive Strength and Porosity
The relation between the compressive strength and the porosity is as follows.
The relation between the Splitting Tensile strength and the porosity is as follows.
Higher the porosity, lower is the compressive strength
Porosity of Aggregates on Concrete Strength
The porosity of the aggregate influences the
- Bond between the cement paste and the aggregate
- Workability of the Fresh Concrete
- Strength of the Concrete