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Into this paper there are presented physical and mechanical properties of control samples from self-compacting concrete realized with fly ash and silica fume (like powders) and superplasticizer. The slump of fresh self-compacting concrete was 680 mm, L-box h1/h2=0.92 and V-funnel = 12 sec. There were realized prismatic samples with dimensions 10 x 10 x 30 cm. The control samples were kept into laboratory curing conditions. The testing ages were at 28 days and 9 years. At 28 days age, the compressive strengths on p...

With clastic sedimentary rocks associated deposits of ore, oil-and-gas, coal and non-metallic minerals. They are located in a variety of different age strata structural-tectonic stages. Sedimentary rocks composing these fields are often framework rocks or minerals themselves are economic minerals. Depending on the age and affinity to specific structural and tectonic tier breeds are in various stages of the penecontemporaneous transformation. By the degree of transformation of organic matter in the clastic rocks ca...

Great problem of mechanical hard rock mining is low durability of mining tools. In Department of Mining, Dressing and Transport Machines, AGH UST in Cracow new solutions of mining tools and their holders were developed. In paper, a special tool to replace traditional rotary pick (so called crown-shaped pick), new lubricated holder for rotary-tangential picks, asymmetrical disc cutters, results of laboratory, field and industrial tests were described. Crown-shaped pick has the same type of handle as standard soluti...