| Abstract [eng] |
Concrete is the most used building material in the world, with production increasing year on year. It plays a significant role in modern construction due to its versatility in shaping, durability, and cost-effectiveness. However, the production of cement used for concrete is highly polluting due to the large amount of carbon dioxide emitted into the atmosphere. The aim is therefore to use sustainable concrete, for which the cement used is supplemented with a certain amount of additives or substitutes to reduce the clinker content. One such additive is opoka. Such concrete with opoka cement has the property of having higher shrinkage deformations at an early age, leading to cracks and fissures. To overcome this problem, chemical admixtures or other additives are used in concrete production to reduce the shrinkage of the concrete. Master‘s final project aim is to investigate the effect of concretes with different binders on the properties of fresh and hardened concrete. The focus is on the study of early and typical shrinkage. The object of the studies is a concrete mix with all the same ingredients and quantities, except for the amount of superplasticizer (to achieve the same slump class for each mix) and the type of binder. An experimental study is carried out to produce four different concrete compositions. Two of them are formulated with a binder containing pozzolans, a type of opoka. The Master's final project consists of three parts. The first part is a literature review, which provides an overview of similar types of research. The second part describes the research methodology, which includes the standards to which the tests are carried out, a description of the materials used and the design of the concrete composition. The third part presents and summarises the results of experimental studies. |
