National Repository of Grey Literature 226 records found  beginprevious217 - 226  jump to record: Search took 0.00 seconds. 
SCC with secondary raw materials
Ťažká, Lucia ; Ťažký, Tomáš (referee) ; Hela, Rudolf (advisor)
Bachelor thesis is focused on the possibility of using secondary raw materials and their application to the production of SCC. Large part deals with impurities of type I and its application results mainly from abroad. Furthermore, this work examines the impact of different types of impurities on the resulting concrete durability in various aggressive environments. The practical part is focused on the use of chemically non-reactive additives of type I instead of the commonly used additives of type II which are used to replace part of cement and the resulting design and manufacture of low-strength SCC using appropriate additives.
Cement composite materials with polypropylene fibers
Preisner, Martin ; Hela, Rudolf (referee) ; Bodnárová, Lenka (advisor)
This thesis deals with summarizing the possible effects of the addition of polypropylene fibers, especially low temperature plasma treated on the properties of cement composites and concrete. They are given basic information and distribution of polypropylene fibers. It describes the finish polypropylene fiber low-temperature plasma. The experimental part focuses on the effect of dispersion of polypropylene fibers treated plasma in the cement matrix.
High volume fly ash concrete
Kučera, Jakub ; Sokol, Pavel (referee) ; Hela, Rudolf (advisor)
Bachelor thesis consist of two parts. The aim of teoretical part is to explore possibilities of usage and properties of high volume fly ash concrete with 40 – 70 % cement replacement. To make an overview of development of strength, durability in various environments, reduction of heat evolution etc. The aim of the experimental part is to compare properties of various class concretes with various amount of fly ash.
Special surface finish architectural concrete
Gajdoš, Jan ; Ťažký, Tomáš (referee) ; Hela, Rudolf (advisor)
The aim of this work is to describe modern methods of finishing concrete with architectural division of the surfaces created in fresh and hardened state. In this work describes the various influences and their effects on the resulting surface such as concrete composition, method of storage or production and compaction of concrete. In the practical part of the thesis focuses on the technology of graphic concrete and its application to vertical monolithic wall.
Production technology of cement foam concrete and their properties
Mikulica, Karel ; Vojtek, Miroslav (referee) ; Hela, Rudolf (advisor)
This bachelor's thesis deals with the technologies of production of the cement foam concrete and about the choise of suitable materials for achieving the desired properties of the foam concrete. The experimental part of the bachelor's thesis is devoted to the comparison the physical properties of the foaming agents and the foam concrete produced of them.
Study of the effect of concrete composition on the abrasion surfaces
Hoško, Marek ; Reiterman, Pavel (referee) ; Hela, Rudolf (advisor)
This work deals with summarizing knowledge on issues related to the loss of skid resistance properties of roads, which is caused by surface abrasion. Then indicates the relation between types of aggregates and paste volume to abrasion, impact compressive strength, aeration rate and different types of finishes. In the practical part were designed recipe CB II with different types of coarse aggregate. Samples were tested for abrasion method according to Böhm according to CSN 73 1324 Determination of abrasion of concrete.
Properties of cementitious composites with plasma treated polymer fibers
Počekajlo, Václav ; Hela, Rudolf (referee) ; Bodnárová, Lenka (advisor)
Modification of polymer fiber low temperature plasma is one of the ways to enhance the properties of modified fibers as follows. This work aims to evaluate the effect of plasma treated polypropylene fibers on the rheological properties of cement composites. The theoretical part describes the treatment and the effect of plasma treatment on polymer fibers. The influence of polypropylene fibers treated by low-temperature plasma on the workability of concrete. The practical part is described and evaluated experimental verification of the influence of the addition of commercially available fibers and fibers treated plasma on the rheological properties of fresh cement composite.
Effect of fly ash on the durability of concrete
Vašek, Tomáš ; Kulísek, Karel (referee) ; Hela, Rudolf (advisor)
Bachelor thesis consists of two parts, theoretical and practical. In the theoretical section provides basic information on the manufacture of fly ash, development and principle of High Volume Fly Ash Concrete and view on this type of concrete in the Czech Republic. Listed below are the world´s knowledge of conduct of durability and potential problems that can act on them. The theoretical part ends with summary of the utilization of fly ash in various areas of construction industry. In the practical part compares the characteristics of each recipe containing fly ash with recipe containing only Portland cement. Finally, is evaluation of results of practical part and influence on the durability of fly ash concrete.
ultra-high-strength concretes
Ambruz, Pavel ; Hubáček,, Adam (referee) ; Hela, Rudolf (advisor)
Thesis deals with summarizing knowledge about production methods of ultra – high – strength concrete (UHSC) and their possible use in practice, which is documented on the existing building. Further work shows suitable raw materials for production UHSC and their availability on the Czech market. The practical part results an experiment whose outcome should be concrete with a compressive strength of 150 MPa.
Activation admixtures in concrete
Eger, Lukáš ; Hela, Vlastimil (referee) ; Hela, Rudolf (advisor)
The aim of my bachelor´s work is the summarization and focus on admixure concrete,and the active and inert admixure, which have some positive characteristies for fresh and hardened concrete. Theoretically, I tried to study the increase of their joining potential while this characteristic can be used by either chemici or mechnical way, their combination as well. I also Works on evaluetion of physically mechanical influence for fresh and hardened concrete that can up to 60 days old while the cement was partly substituted by admixure of different character.

National Repository of Grey Literature : 226 records found   beginprevious217 - 226  jump to record:
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