Osman Aygül / Certification Specialist CPC Belgelendirme
Cement; It is the main binder of mixtures such as concrete, mortars and grouts. Therefore, cement plays a very important role in the performance and durability of mixtures. Accordingly, the choice of cement has a great impact on the durability, strength and longevity of structures.
As it is known, TS EN 197-1 and TS EN 206 standards include the following: The cement type to be used must comply with the intended use, environmental conditions and legislation. So we cannot choose the cement type randomly, thus we need to choose by considering the following factors;
1. Strength and Durability: Different types of cement have different chemical compositions and properties that can affect the strength and durability of concrete.
2. Climatic Conditions: Cement types used in cold climates should be more resistant to the freeze-thaw cycle. In hot and humid climates, water-resistant cement should be preferred.
3. Workability and Setting Time: Cement type and composition can affect the workability of fresh concrete, making it easier or harder to handle during placement and finishing. Setting time, which determines when concrete will harden and begin to gain strength, can also be affected by the type of cement used. When choosing cement, the desired workability and setting time requirements should be taken into account.
4. Resistance to Chemical Attacks: Concrete is frequently exposed to a variety of chemicals such as sulfates, acids and chlorides that can destroy its structure. The choice of cement can significantly affect concrete’s resistance to such chemical attack. Certain types of cement, such as sulfate-resistant cement or blended cements, can increase the durability of concrete in aggressive environments.
5. Cost and Availability: Factors such as cost and availability are also taken into consideration when choosing cement. Different types of cement may have different costs and availability may vary by region. It is important to balance desired performance requirements with practical considerations to ensure an optimal choice.
6. Environmental Issues: Cement production is one of the largest sources of emissions in the world. Therefore, the industry needs to develop more sustainable and environmentally friendly cement options. Contributing to more sustainable construction practices can be achieved by considering factors such as carbon footprint, recycled content and energy consumption of cement when choosing cement.
The increase in demand for other cement types containing high amounts of alternative components, instead of CEM I, which consists almost entirely of clinker, will contribute greatly to the reduction of costs and emissions, first in cement and then in concrete.
Until recently, “CEM I” class cements were generally preferred in concrete recipes. Especially in recent years, with the pressures brought by environmental and financial concerns, cement factories have carried out studies in their regions to use additive cement types. As a reward for the efforts made, the use of blended cement is increasing in our country.
The use of non-clinker components in cement is specified in TS EN 197-1, TS EN 197-5, TS EN 14647, TS EN 413, TS EN 15743 etc. sets by these standards. In this case, the cement producer cannot go beyond certain patterns. Unfortunately, the technical specifications in question are inadequate today. However, the placing on the market and use of non-standard alternative cements is possible with European Technical Assessment or National Technical Approval. In short, it is possible to market supply and use of cement types with additives (containing non-clinker components) whether or not they comply with existing standards.
