# water cement ratio table

So, the lower the w/c, the lower is the void volume/solid volume, and the stronger the hardened cement paste. Water-Cement Ratio = Weight of water/ Weight of cement. 0.4 w/c ratio –> 5600 psi. Adding water to the concrete beyond this limit will affect the cement paste strength and eventually breaks the concrete strength. The most important factor determining the strength of concrete is the water to cement ratio. The aggregate-cement ratio represents the volume of cement paste in a concrete for a given water-cement ratio. It is very simple relation and it is like the same as presented by Rene Feret in 1896. Limitation chart for w-c ratio shows the maximum value of the w-c ratio as per IS 456: 2000 which can be adopted during mix design. From this table for ordinary port-land cement and uncrushed 20 mm aggregate the 28 days strength is 42 MPa. You can use this table for the water-cement ratio of different grade of concrete. DO YOU KNOW – What is FIRE PROOF CONCRETE ?? Calculate water-cement ratio from the maximum free water/cement ratio according to environmental exposure condition as per table 5 of 456-2000, this is the limitation given by Indian Standard. For instance, if water required for, 1 bag of cement is 30 litres, the water-cement ratio is equal to 30/50= 0.60. The strength of this mix ratio is good for most concrete slabs, footings, steps, and foundation walls. Quantity of water = W/C ratio * Quantity of cement So the required quantity of water is 19.1 Liters per cement bag. Concrete Requirements • Min. But actually, strength at any water-cement ratio depends upon the “degree of hydration” of cement. Let us calculate water quantity for 1 bag of cement. Hello John, Thanks for the suggestion. M15 Ratio 1:2:4cement = 317 Kg (unit weight = 1440 kg/cum), Sand = 638 Kg (unit weight = 1450 Kg/cum), Blue Metal = 1478 Kg (unit weight = 1680 Kg/Cum). We well knew the quantity of water is very important while concrete mixing or mortar because the durability and strength of concrete depend on the water consumption in concrete. Suppose you are casting M15 concrete for Moderate condition, the maximum w/c ratio is 0.6. Adding too much water affects the quality of the concrete or cement mortar. The traditional way to estimate the w/c-ratio by weighing the cement and water from mix design. The purpose of water in concrete to composite the Cement, Sand and Coarse aggregate. The conventional relation between strength and water-cement ratio will hold good primarily for 28 days strength for fully compacted concrete. Also concrete will experience more shrinkage as the excess water leaves, resulting in internal cracks and visible fractures (particularly around inside corners) which again will reduce the final strength. As per general practice for 1:1½:3 concrete mix 25-30 litres water should be added per 50 kg of cement (one bag) depending upon the temperature, humidity and water associated with sand and aggregate (if any). In our case it is IS Code 10262. Water Cement Ratio Test The total weight of water includes all … Higher aggregate-cement ratio means, larger volume of concrete is occupied by the aggregates hence less proportion of cement paste. Where; fc is the concrete strength. A slight change in the amount of water causes much more differences in the strength of concrete. W/c is the water to cement ratio in the concrete mix. The quantity of water is usually expressed in litres per bag of cement and hence the water-cement ratio reduces to the quantity of water required in litres per kg of cement as 1 litre of water weighs 1 kg. What is the full form of 1BHK, 2BHK, 2.5BHK? For Design mix, the W/C Ratio will depend upon the workability, strength requirements. He is an Author and Co-Founder at ProCivilEngineer.com Website. (a) Weight of water = of the weight of the cement + 4% of the weight of total aggregate. This ratio of the amount of water to the amount of cement by weight is termed as the water-cement ratio and the strength and quality of concrete primarily depend upon this ratio. So the extra water will float above the concrete and make the uneven coarse aggregate segregation. Here is the comprehensive table for concrete mix ratio of various grades of concrete (M7.5, M10, M15, M20, M25, M30, M35, M40), with water content ratio. It is found theoretically that water required for these two functions is about 0.50 to 0.60 times the weight of cement. In IS 10262-2009 ANNEX A. they have explained the process for design mix. On the other hand, if the water is used more, it may develop larger voids and honey-combing in the set concrete, in this way decreasing its density, durability, and strength. We can’t calculate the water-cement ratio. From Example, Calculate Water Cement Ratio for M20 RCC, From the table, we know the water-cement ratio is 0.55 for M20. Quantity of water = 0.42 x 50 = 21 Liters (1 bag cement = 50 Kg). Effect of Sand Fines and Water/Cement Ratio on Concrete Properties. Water-to-cement ratio is a critical factor determining the quality and durability of concrete. The two such rules are mentioned below.