Answer / guest

there is no ratio for m50 grade concrete. it is fully based
on design mix. following steps should be followed while you
consider design mix.

Grade Designation = M-50
Type of cement = O.P.C-43 grade
Brand of cement = Vikram ( Grasim )
Admixture = Sika [Sikament 170 ( H ) ]
Fine Aggregate = Zone-II

Sp. Gravity
Cement = 3.15
Fine Aggregate = 2.61
Coarse Aggregate (20mm) = 2.65
Coarse Aggregate (10mm) = 2.66

Minimum Cement (As per contract) =400 kg / m3
Maximum water cement ratio (As per contract) = 0.45

Mix Calculation: -

1. Target Mean Strength = 50 + ( 5 X 1.65 ) = 58.25 Mpa

2. Selection of water cement ratio:-
Assume water cement ratio = 0.35

3. Calculation of water: -
Approximate water content for 20mm max. Size of aggregate
= 180 kg /m3 (As per Table No. 5 , IS : 10262 ). As
plasticizer is proposed we can reduce water content by 20%.

Now water content = 180 X 0.8 = 144 kg /m3

4. Calculation of cement content:-
Water cement ratio = 0.35
Water content per cum of concrete = 144 kg
Cement content = 144/0.35 = 411.4 kg / m3
Say cement content = 412 kg / m3 (As per contract Minimum
cement content 400 kg / m3 )
Hence O.K.

5. Calculation for C.A. & F.A.: [ Formula's can be seen in
earlier posts]-

Volume of concrete = 1 m3
Volume of cement = 412 / ( 3.15 X 1000 ) = 0.1308 m3
Volume of water = 144 / ( 1 X 1000 ) = 0.1440 m3
Volume of Admixture = 4.994 / (1.145 X 1000 ) = 0.0043 m3
Total weight of other materials except coarse aggregate =
0.1308 + 0.1440 +0.0043 = 0.2791 m3

Volume of coarse and fine aggregate = 1 – 0.2791 = 0.7209 m3
Volume of F.A. = 0.7209 X 0.33 = 0.2379 m3 (Assuming 33%
by volume of total aggregate )

Volume of C.A. = 0.7209 – 0.2379 = 0.4830 m3

Therefore weight of F.A. = 0.2379 X 2.61 X 1000 = 620.919
kg/ m3

Say weight of F.A. = 621 kg/ m3

Therefore weight of C.A. = 0.4830 X 2.655 X 1000 = 1282.365
kg/ m3

Say weight of C.A. = 1284 kg/ m3

Considering 20 mm: 10mm = 0.55: 0.45
20mm = 706 kg .
10mm = 578 kg .
Hence Mix details per m3
Increasing cement, water, admixture by 2.5% for this trial

Cement = 412 X 1.025 = 422 kg
Water = 144 X 1.025 = 147.6 kg
Fine aggregate = 621 kg
Coarse aggregate 20 mm = 706 kg
Coarse aggregate 10 mm = 578 kg
Admixture = 1.2 % by weight of cement = 5.064 kg.

Water: cement: F.A.: C.A. = 0.35: 1: 1.472: 3.043

Observation: -
A. Mix was cohesive and homogeneous.
B. Slump = 120 mm
C. No. of cube casted = 9 Nos.
7 days average compressive strength = 52.07 MPa.
28 days average compressive strength = 62.52 MPa which is
greater than 58.25MPa
Hence the mix accepted.

A person becomes tired when ups a stairs because of––

1 Answers  

---

How steel required for 823 sqm of flooring work in 150mm c/c in single jali?

1 Answers  

---

can any one explain bar bending schedule of bems and columns and slabs ??

0 Answers  

---

Given a selection of 28 day cube test results for concrete placed of design mix C 35 and not all of which are greater then 35 MPa, how does one decide if the concrete in place is satisfactory. Are there a minimum number of cubes that need to be tested to decide that?

2 Answers   RPS,

---

what is meant by concrete joints?

1 Answers   NBCC,

---

Design a reinforced concrete combined footing (rectangular) for two columns located 3.60 metres apart. The overall sizes of the columns are 40cm x 40cm and 69cm x 60cm and the loads on them are 1000 kn and 1500 kn respectively. The space available for the width of the footing is restricted to 180cm. The S.B.C. of the soil is 280 kn/mm2 use M15 concrete.

0 Answers  

---

WHAT IS IS CODE FOR USE TOR & TMT STEEL

1 Answers  

---

what is the standard size of brick available in site in mm

6 Answers  

---

How could I calculate quantities of fine aggrigates(sand) & coarse aggregates in pcc M15

1 Answers   Coromandel, RECPDCL,

---

what is pile and deam foundation

0 Answers   DLF,

---

What is the stripping time of shuttering for PPC concrete

1 Answers  

---

What is the difference between gray swr pipe & red swr pipe

1 Answers  

---