- Density of M20,M25 and M30 is to be taken as
**25kn/m****³****.**

- Similarly for higher grade of concrete and for high strength of concrete up to M60 grade of concrete the density will be
**27.5****kn****/****m³****.** - For Ultra high strength concrete like M80 & M100 the density of concrete will be in the range of
**29****kn****/m³**.

Because the particle packing density will be very high, Void are very less & aggregate interlocking will be very superior. - Density or unit weight of plain concrete is to be taken as 24 kn/
**m³**

The reason behind all grade of concrete not having same unit weight is “ As the grade of the concrete increases

- Particle packing density will increase
- voids will decrease
- Aggregate interlocking will increase”