**1. REQUIREMENTS**

a) Specified minimum strength = 20 N/Sq mm

b) Durability requirements

i) Exposure Moderate

ii) Minimum Cement Content = 300 Kgs/cum

c) Cement

(Refer Table No. 5 of IS:456-2000)

i) Make Chetak (Birla)

ii) Type OPC

iii) Grade 43

d) Workability

i) compacting factor = 0.7

e) Degree of quality control Good

**2. TEST DATA FOR MATERIALS SUPPLIED **

a) CEMENT

i) Specific gravity = 3.05

ii) Avg. comp. strength 7 days = 46.5 more than 33.0 OK

28 days = 55.0 more than 43.0 OK

b) COARSE AGGREGATE

i) 20mm Graded

Type Crushed stone aggregate

Specific gravity = 2.68

Water absorption = 1.46

Free (surface) moisture = 0

c) FINE AGGREGATE (Coarse sand)

i) Type Natural (Ghaggar)

Specific gravity = 2.6

Water absorption = 0.5

Free (surface) moisture = 1.4

**3. TARGET MEAN STRENGTH (TMS)**

a) Statistical constant K = 1.65

b) Standard deviation S = 4.6

Thus, TMS = 27.59 N/Sqmm

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**4. SELECTION OF W/C RATIO**
a) As required for TMS = 0.5

b) As required for ‘Moderate’ Exposure = 0.55

Assume W/c ratio of 0.5

**5. DETERMINATION OF WATER & SAND CONTENT**

For W/C = 0.6

C.F. = 0.8

Max. Agg. Size of 20 mm

a) Water content = 186 Kg/cum

b) Sand as percentage of total aggregate by absolute volume = 35 %

Thus,

Net water content = 180.42 Kg/cum

Net sand percentage = 33 %

**6. DETERMINATION OF CEMENT CONTENT**

W/c ratio = 0.5

Water content = 180.42 Kg/cum

Thus, Cement content = 360.84 Kg/cum Adequate for moderate exposure Say 360 Kg/cum

**7. DETERMINATION OF COARSE AND FINE AGGREGATE CONTENT**

Assume entrapped air as 2 %

Thus,

0.98 cum = [180.42+360/3.05 + {1/0.33}*{fa/2.6}]/1000

& 0.98 cum = [180.42+360/3.05 + {1/0.67}*{Ca/2.68}]/1000

Hence,

fa = 584 Kg/cum

Ca = 1223.8 Kg/cum

The final mix proportions of M-20 grade of concrete become:-

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Note: 1 The above recommended mix design must be verified, by actual cube tests.

2 The mix design is based on the quality and grading of the materials actually supplied, by the client.

Any variation in quality and gradation will result in changes in the mix design.

This mix design was submitted by a regular contributor to this site. We are thankful to him for his excellent service.

### Kanwarjot Singh

Kanwarjot Singh is the founder of Civil Engineering Portal, a leading civil engineering website which has been awarded as the best online publication by CIDC. He did his BE civil from Thapar University, Patiala and has been working on this website with his team of Civil Engineers.
If you have a query, you can **ask a question here**.

Can you send me M20 contents as per IS 456: 2000

plz send me the mix designe M20 , M15 & M10

many kinds of steel.

Dear Sir,

Please send me the M-20 Concrete details & tell me how to calculate the quantities for 1 cum concrete?

CAN U SEND ME A DETAILED CALCULATION OR PROPORTION GRADE 20,25,30,35 AND 40.THANK U

DEAR SIR,

PLEASE SEND ME THE MIX DESIGN FOR ALL THE GRADES. AS I AM A CIVIL ENGINEER.I VIL BE HELPFUL TO YOU SIR IF U DO TAT.

hi sir,

i want mix desing for M-10,M-15,M-20,M-25 concrete

plz send.

Dear Sir/Madam,

Please send the mix design for M-10,M-15,M-20,M-25,M-30,M-40 Concrete for which il be greatful to you.

DEAR SIR

PLEASE SEND THE MIX DESIGN CALCULATIONS WITH IS STD METHOD FOR M-25,M-35 CONCRETE

THIS WILL BE HELP ME IN MY PRACTICE. THANKING U

SANTOSH-DIPLOMA CIVIL

Dear Sir,

I want to know what is the quantity (kgs) of Cement, Sand & Aggregates present in 1 cum of concrete with 1:2:4 mix & in 1:4:8 mix.

Please help me, i want to calculate the total quantity of materials required.

Also give me the details for calculation of steel quantities.

Dear Sir plz send me an IS Code: 516-1959 (test for strength of concrete).

CAN U SEND ME A DETAILED CALCULATION OR PROPORTION GRADE 20,25,30,35,40 and 55.THANK U

dear sir i am a civil engineer working privet sector i would like to know from you

how will effect bulk of sand in concrete mix how will design the mix.

kindly mail me sir

thanking you nsir

yours faith fully

rafiqe pm

bangalore

Sir,

pls me send of detail calculation of Mix Design of M15,20,25 &30 as soon as possible.

Thanks

Sir,

i am a civil engineer

Please sendf PROPORTION GRADE 20,25,30,35,40 Min. and max. steel requirment,where use these grade, total quantity of materials required.

and difference of desing mix & mix desing

Please send the concrete mix design M15,M20, M25, M30& M35

Thanks

sir please clear me the following doubts.

1. volume of the cement.

2. how to calculate the volume of the cement.

also pls send me how to design the shuttering for concrete.

Eg.:- how to design shutteringfor normal slabs and cantilever slabs.

please send me the cement, sand, metal ratio of M 15,20,25,30,35

please send me the cement, sand, metal ratio of M 15,20,25,30,35

Cude test method of concrete

dear sir…

i am a student from civil engineering faculty.can you send me the concrete mix design for M25 grade….

i really need it immediately before this 23rd of july….please…