C28/35 is a designation used to specify the compressive strength of concrete, indicating its characteristics and performance. In this case, “C” stands for concrete, and the numbers 28 and 35 represent the characteristic compressive strength of the concrete in megapascals (MPa).

Here’s a breakdown of the information:

Compressive Strength (C): This indicates that the concrete is designed to withstand a certain amount of compressive force without failing. It is a crucial parameter in determining the overall durability and load-bearing capacity of the concrete.

28 MPa: The number 28 represents the characteristic compressive strength of the concrete at 28 days of curing. Concrete gains strength over time as it cures, and the 28-day mark is a standard reference point for testing and assessing its strength.

35 MPa: The number 35 represents the specified maximum compressive strength of the concrete. This means that the concrete should achieve a minimum compressive strength of 28 MPa at 28 days and should not exceed 35 MPa. This range ensures that the concrete is suitable for its intended application and meets the required performance criteria.

In practical terms, C28/35 concrete is a medium-strength concrete mix commonly used in various construction applications where moderate strength is required. This may include residential buildings, commercial structures, pavements, and other construction projects where a balance between strength and workability is essential. The mix design for C28/35 concrete would typically involve carefully proportioning the components, such as cement, aggregates, water, and admixtures, to achieve the desired strength and durability properties.