The purpose of the thesis is to monitor carbonation process and mechanical characteristics of lime injection grouts. Lime grout with selected composition was cast in standard prisms of 40 mm x 40 mm x 160 mm. The prisms were demoulded after 7 days and after that they were exposed to different ageing conditions. First, one half of the prisms were exposed to the laboratory ambient conditions (air) and the second half were put into containers with a cover made of lime mortar. Especially for the purpose of the diploma thesis Plexiglas containers were designed and produced, along with a wooden frame and a net, as supporting system for the lime render which acts as the cover. The lime render cover simulates lime render or plaster on wall or ceiling. In different time periods (1M, 2M, 3M, i.e. one months, two months and three months after demoulding of the prisms), we performed flexural and compressive tests on the prisms as well as a phenolphthalein test for monitoring the carbonation process. Every month, we opened one container and performed the tests on the prisms from the container, parallel to the tests carried out on air-dried prisms. The obtained results were analysed and comparison between mechanical properties and carbonisation depth was made. We established that the carbonization process in the containers with a limited inflow of CO2 is very slow. The results of mechanical tests show that in all time periods, the obtained average values of flexural tensile strength, as well as the compressive strength of the prisms dried in the container, were lower than the same characteristics of air-dried prisms. After the first month phenolphthalein test carried out on the prisms aged in the container did not show start of carbonisation. However, the prisms showed, despite high humidity in the container, an increase in mechanical characteristics. We presume that the obtained results are combination of two influencing parameters – drying of the prisms and start of alkali carbonate reaction.
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