Ordinary concrete- M10,M15,M20
Standard Concrete-M25,M30,M35,M40,M45,M50,M55
High Strength concrete-M60,M65,M70,M75,M80
Here are two grades also specified in BIS for lean concrete
M5 and M7.5
Where M refers to Mix and the given no. specified the
characteristics compressive strength of 150 mm cube after 28
days curing on normal temperature..

In the designation of a concrete mix,letter M refers to the mix and the number to the specified characteristic compressive strength of 15 cm. cube at 28 days,express in N/mm2.As a example M25 = 25 N /mm2 or 250 Kg./cm2 (app).

Ordinary concrete- M10,M15,M20
Standard Concrete-M25,M30,M35,M40,M45,M50,M55
High Strength concrete-M60,M65,M70,M75,M80
Here are two grades also specified in BIS for lean concrete
M5 and M7.5
Where M refers to Mix and the given no. specified the
characteristics compressive strength of 150 mm cube after 28
days curing on normal temperature..

Ordinary concrete- M10,M15,M20
Standard Concrete-M25,M30,M35,M40,M45,M50,M55
High Strength concrete-M60,M65,M70,M75,M80
Here are two grades also specified in BIS for lean concrete
M5 and M7.5
Where M refers to Mix and the given no. specified the
characteristics compressive strength of 150 mm cube after 28
days curing on normal temperature

how to calculate cutting length in bar bending schedule for
180 degree bend? for 90 degree bend we take 2d i.e we -2d
for 180 degree ho much ? question asked at l&t

plz tell.. how can we find weight(in kg) of 1 cum of m20
mix..? how can we find the ratio of cement sand and
agregate on site i.e if we given some amount of m20 mix
then hw we find the ratio..?