The aim of the master thesis was to develop lightweight self-compacting concrete made of lightweight aggregate and with declared properties, such as compressive strength class and maximal target density. Self-compacting properties were determined by measuring rheological properties and selecting the optimum range of yield stresses and plastic viscosities as a result of these measurements. In the first part of the thesis properties and specifications of lightweight aggregate and lightweight concrete are given. The data were obtained using relevant literature and standards. Common explanations about rheology of concrete and models for the description of liquids are also given, along with presentation of ultrasound testing and thermal current measurements. The second part of the thesis, which is experimental, represents the main part of my work. First the used test methods are given and the testing protocols are described, with obtained results of the tests. After that the test results are analysed. Concrete mixtures were divided in two groups. Preliminary concrete mixtures were first tested in order to define the composition of the main group of the mixtures. For the main mixtures rheological properties were first measured for different influencing parameters and presented in the form of rheographs. Then selected mixture was used to cast a concrete wall of 100 cm x 230 cm x 6 cm. The homogeneity of concrete in the wall was evaluated using ultrasound testing. The thermal insulation properties of the concrete were evaluated using thermal flow measurements. The study was carried out in the framework of cooperation with an enterprise that uses such concretes in practice.
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