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Effect of Cement Bypass Dust on Cracking Tendency of Alkali-Activated Slag during Drying
Krejčová, Marie ; Švec, Jiří (referee) ; Bílek, Vlastimil (advisor)
This bachelor thesis deals with the influence of bypass cement dust on cracking of alkali activated slag. Significant shrinkage and cracking prevent greater use of alkali activated slag. The length changes and strength of the mixtures with different amount of bypass cement dust were measured at various curing conditions. In these mixtures, cracks were observed and their amount was evaluated by image analysis. It has been found that the addition of dust can reduce the amount of cracks. Treating the prisms in a humid environment leads to a reduction of cracks, especially during long-term treatment. In order to improve flexural and compressive strength, it is preferable to use dust as a replacement for part of aggregates and not as a partial slag replacement.
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Effect of cement by-pass dust on properties alkali-activated slag
Janíčková, Vlasta ; Kalina, Lukáš (referee) ; Bílek, Vlastimil (advisor)
This masters thesis deals with influence of cement bypass kiln dust on physico-mechanical properties of alkali activated slag and influence of chosen compounds of cement bypass kiln dust on alkali activated slag. Using alkali activated slag is limited by its shrinkage. The setting time with different amount of cement bypass kiln dust and its chosen compounds (CaO, KCl and K2SO4) were measured by isotermal and isoperibolic calorimetry too. The strength and length changes of the mixtures with different amount of cement bypass kiln dust were measured. Samples were analysed by X-Ray diffraction analysis and scanning electron microscopy. It has been found that the increasing addition of dust reduce setting time, flexural and compresive strength and shrinkage. Presence of free CaO was found being one of the reasons for accelerated setting. KCl and K2SO4 have retarding effect but influece of free CaO prevails even for its lower contents. Long-term properties evolution is strongly dependent on curing regime due to potential volume expansion.
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Roman forts and fortresses in the Nile valley
Šurinová, Miroslava ; Musil, Jiří (advisor) ; Titz, Pavel (referee)
This paper deals with roman fortifications in the Nile valley from the mouth of Delta to site of Qasr Ibrim located between first and second cataract. Period described in this paper can be limit by two dates. Beginning lay in the year 30BC, when Egypt became a roman province. The end of this period is year AD 641, when the city of Alexandria capitulated to Arab conquerors. The paper focuses on the architecture of forts and archaeological excavations.
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Effect of cement by-pass dust on properties alkali-activated slag
Janíčková, Vlasta ; Kalina, Lukáš (referee) ; Bílek, Vlastimil (advisor)
This masters thesis deals with influence of cement bypass kiln dust on physico-mechanical properties of alkali activated slag and influence of chosen compounds of cement bypass kiln dust on alkali activated slag. Using alkali activated slag is limited by its shrinkage. The setting time with different amount of cement bypass kiln dust and its chosen compounds (CaO, KCl and K2SO4) were measured by isotermal and isoperibolic calorimetry too. The strength and length changes of the mixtures with different amount of cement bypass kiln dust were measured. Samples were analysed by X-Ray diffraction analysis and scanning electron microscopy. It has been found that the increasing addition of dust reduce setting time, flexural and compresive strength and shrinkage. Presence of free CaO was found being one of the reasons for accelerated setting. KCl and K2SO4 have retarding effect but influece of free CaO prevails even for its lower contents. Long-term properties evolution is strongly dependent on curing regime due to potential volume expansion.
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Effect of Cement Bypass Dust on Cracking Tendency of Alkali-Activated Slag during Drying
Krejčová, Marie ; Švec, Jiří (referee) ; Bílek, Vlastimil (advisor)
This bachelor thesis deals with the influence of bypass cement dust on cracking of alkali activated slag. Significant shrinkage and cracking prevent greater use of alkali activated slag. The length changes and strength of the mixtures with different amount of bypass cement dust were measured at various curing conditions. In these mixtures, cracks were observed and their amount was evaluated by image analysis. It has been found that the addition of dust can reduce the amount of cracks. Treating the prisms in a humid environment leads to a reduction of cracks, especially during long-term treatment. In order to improve flexural and compressive strength, it is preferable to use dust as a replacement for part of aggregates and not as a partial slag replacement.
|
|
|
Roman forts and fortresses in the Nile valley
Šurinová, Miroslava ; Musil, Jiří (advisor) ; Titz, Pavel (referee)
This paper deals with roman fortifications in the Nile valley from the mouth of Delta to site of Qasr Ibrim located between first and second cataract. Period described in this paper can be limit by two dates. Beginning lay in the year 30BC, when Egypt became a roman province. The end of this period is year AD 641, when the city of Alexandria capitulated to Arab conquerors. The paper focuses on the architecture of forts and archaeological excavations.
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