| Abstract [eng] |
The aim of this master‘s thesis is to make lightweight concrete using green technology by curing in CO2 environment and to determine its properties. The tasks of this thesis are to produce lightweight foam concrete and to determine its mechanical and physical properties after curing in CO2 environment, as we as to estimate the amount of CO2 absorbed by concrete. Master’s thesis consist of three main parts: literature analysis, composition of concrete and research methods, analysis of experimental results. The analysis of literature describes the methods of production of lightweight concrete and materials required for its production. The basic principles of carbonization, its chemical reactions and carbonation methods were found out. The results of other research and possible influence of environment conditions have been analyzed. In the following section making and compositions of lightweight foam concrete which is used in this work are given. Experiments were performed to select best concrete which will be used to continue testing. One composition with a cement binder and one composition with lime binder were chosen. In this section test methods and devices used are also described. The results of experiments are analyzed in the third part of this work. Test have shown that density of both compositions with cement and lime binder cured in CO2 are always higher than the one cured in the air, due to the formation of calcium carbonate. Also tests have shown that, curing time has significant effect on the compressive strength of the concrete, but it’s not worth to keep specimens in the curing chamber for too long, because effectiveness decreases as time goes. The average depth of carbonation indicated that only few hours of curing in CO2 is enough, to achieve a greater carbonation than specimens which were stored in the air for 28 d. In this part of the work samples consumption of the CO2 was estimated by two methods, density change method and titration method. It’s found that the amount of CO2 used is also highly dependent on the curing time, but specimens with lime binder can absorb more carbon dioxide than specimens with cement binder due to their chemical composition. Finally 6 conclusions were made about results of all the experiments. Master’s thesis consists of 53 pages of text, 24 tables, 23 figures, 43 references. |
