less than one year

1 to 5 years

5 to 10 years

more than 10 years

15%

20%

22%

25%

3.5 N/mm2

7.0 N/mm2

10.5 N/mm2

14.0 N/mm2

to impart plasticity

to make the brick durable

to prevent shrinkage

to make the brick impermeable

5 to 10%

20 to 30%

50 to 60%

70 to 80%