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Self-compacting concrete is one of 'the most revolutionar development' in concrete research; this concrete is able to flow and to fill the most restacted places of the form work without vibration. There are several methods for testing it's properties in the fresh state: the most frequently used are slum-flow test, L-box and V-funnel. This work presents properties of self-compacting concrete, mixed with different types additives: fly ash, silica fume, hydraulic lime and a mixture of fly ash and hydraulic lime

Especially geopolymers are novel environmental friendly materials, with promises of considerable progress in the near future. These materials, with unique physical, chemical and mechanical properties can be used for many different applications. They are produced by using waste-products from the industry, and turning them into a high value construction material needed for infrastructure developments.

This paper presents the testing of the durability of concrete where a part of cement was replaced with ground panel cathode ray tube glass (CRT) finer than 63 µm. The percentage of cement replaced with glass is 5%, 10%, 15%, 20%, and 35%, by mass. The highest percent share of mineral admixtures in CEM II (Portland-composiste cement) cement was chosen as the top limit of replacement of cement with glass. In terms of the concrete durability, the following tests are performed: freeze-thaw resistance, freeze-thaw resistance with de-icing salts-scaling, resistance to wear according to the Böhme test, sulfate attack resistance, and resistance to penetration of water under pressure. A compressive strength test is performed, and shrinkage of concrete is monitored. In order to determine the microstructure of concrete, SEM (Scanning Electron Microscopy) and EDS (Energy Dispersive X-ray Spectroscopy) analyses were performed. The obtained research results indicate that the replacement of a part of cement with finely ground CRT glass up to 15% by mass has a positive effect on the compressive strength of concrete in terms of its increase without compromising the durability of concrete. The results obtained by experimental testing unequivocally show that concrete mixtures made with partial replacement (up to 15%) of cement with finely ground CRT glass have the same freeze-thaw resistance, resistance to freeze/thaw with de-icing salt, resistance to wear by abrasion, and resistance to sulfate attack as the reference concrete. In terms of environmental protection, the use of CRT glass as a component for making concrete is also very significant.

This paper presents the results of tests of physical-mechanical, durability and microscopic properties of geopolymer mortar mixtures based on fly ash and ladle slag. The mixtures are alkali-activated using sodium silicate and sodium hydroxide solution. Firstly, the effects of different fly ash (class ?F?) particle sizes on the characteristics of the mortar mixtures were examined when binder and alkali activator were cured at 95?C for 24 h, also pozzolanic activity and strength activity index were investigated. After that, fly ash ground of optimal particle sizes (0,09 mm) was replaced with ladle slag, 0 to 20% of the mass, the replacement steps being 5%. The specimens having dimensions 4x4x16 cm were then cured in ambient conditions, and the effects of replacement of a part of fly ash with ladle slag were determined by testing water absorption, flexural and compressive strength, freeze-thaw resistance, sulfate attack, ultrasound velocity, FT-IR spectroscopy and leaching of heavy metals. According to the test results of compressive strength resistance of geopolymer mortars exposed to sulfate solution, the mortar made with fly ash and ladle slag showed better resistance to sulfate attack than the mortar made with fly ash only.