How to prepare mix design for concrete.

Concrete Mix Design

Mix design is a method to fix the different ratios of ingredients for preparing a concrete mass by mass or by volume.

In detail column for Grades of Concrete denotes 28 days compressive strength of a cube or block.
 In order to require high compressive high compressive strength ratios of material is increased.
for Example
M5
28 Days strength =   5MPa
28 Days strength = 725.19Psi

Conversion Factor
1MPa = 145.038Psi


Let us calculate how to calculate required quantities for a known volume (1m3)
M25     1:1:2


Cement =  ((1/(1+1+2))*1.54*1)/.035 = 11 Bags
Sand     =     11*.035= .33m3
Crush   =      2*.035*11 = .77m3