What is the typical ratio of cement, sand and aggregate for RCC (M20 grade)?

Explanation:

The typical mix ratio for M20 grade RCC (Reinforced Cement Concrete) is: 1 : 1.5 : 3

In this mix, the proportions are:

• 1 part cement

• 1.5 parts sand (fine aggregate)

• 3 parts aggregate (coarse aggregate)

M20 grade concrete is designed to have a compressive strength of 20 MPa (megapascals) at 28 days of curing. This ratio is commonly used for medium-strength concrete in construction.

Additional Information

M20 Grade Concrete:

1. It is a medium-strength concrete mix suitable for general construction purposes such as foundations, beams, slabs, and pavements.

2. The number "20" in M20 refers to the compressive strength of the concrete, which is 20 MPa (megapascals) after 28 days of curing.

Mix Proportions:

1. The mix ratio of 1:1.5:3 (cement: sand: coarse aggregate) is commonly used for M20 grade concrete.

2. This is a nominal mix, often used when the exact properties of materials are unknown or when specific mix design is not needed.

Water-Cement Ratio:

1. The water-cement ratio plays a crucial role in the strength and durability of concrete.

2. For M20 grade, the water-cement ratio is usually around 0.5 to 0.6 to achieve optimal strength and workability.

Strength Consideration:

1. Concrete's strength increases over time with curing, but it is typically tested at 28 days to determine whether it has achieved the desired compressive strength.

Testing:

1. M20 concrete is often tested using a cube compression test, where a 150 mm x 150 mm x 150 mm concrete cube is tested after 28 days to check if it has achieved the expected strength.

Applications:

1. M20 grade concrete is used in elements such as foundations, slabs, beams, footings, and other structural elements where moderate strength is required.