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This paper deals with the issue of additive technologies using glass. At the beginning, our research dealt with a review of the current state and specification of potentially interesting methods and solutions. At present, this technology is being actively developed and studied in glass research. However, as the project started at the Department of Glass Producing Machines and Robotics, the following text will be more focused on the existing 3D printing machinery and basic technological approaches. Although “additive manufacturing” in the sense of adding materials has been used in glass manufacturing since the beginning of the production of glass by humans, the term additive manufacturing nowadays refers to 3D printing. Currently, there are several approaches to 3D printing of glass that have various outstanding advantages, but also several serious limitations. The resulting products very often have a high degree of shrinkage and rounding (after sintering), and specific shape structures (after the application in layers), but they generally have a large number of defects (especially bubbles or crystallization issues). Some technologies do not lead to the production of transparent glass and, therefore, its optical properties are significantly restricted. So far, the additive manufacturing of glass do not produce goods that are price competitive to goods produced by conventional glass-making technologies. If 3D glass printing is to be successful as an industrial and/or highly aesthetically valuable method, then it must bring new and otherwise unachievable features and properties, as with 3D printing of plastic, metal, or ceramics. Nowadays, these technologies promise to be such a tool and are beginning to attract more and more interest.

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Long-term objective of rheological sliding joints research is to contribute to updating the existing computational methods for their design. Sliding joints are applied in foundation structure to reduce the friction which is caused in footing bottom due to horizontal deformation loading (e.g. effect of undermining, pre-stressing). Accuracy of rheological sliding joints design depends on knowledge of the mechanical properties of used materials. The most common material for sliding joint are asphalt belts, which are tested at Faculty of civil engineering using own testing equipment and temperature controlled room. Currently, series of measurements have been carried out so that the results could be used for the numerical modeling. This papers aim is to present possible approaches to asphalt belt sliding joint numerical modeling in foundation structure and summarize their advantages and disadvantages. KeywordsSliding joint, asphalt belt, foundation structures, modeling of sliding joint. AbstraktDlouhodobým výzkumným cílem problematiky reologických kluzných spár je přispět k aktualizaci stávajících výpočetních metod pro jejich navrhování. Aplikace kluzné spáry do základové konstrukce se využívá pro snížení tření, které může v základové spáře vznikat od účinků vodorovných zatížení (např. od vlivu poddolování). Správnost návrhu reologické kluzné spáry závisí především na znalosti mechanických vlastností materiálu kluzné spáry, nejčastěji asfaltových pásů, které se na fakultě stavební testují s využitím vlastního měřícího zařízení a klimatizační komory. V současné době neustále probíhá řada měření a výsledky jsou využívány např. pro numerické modelování. Tento příspěvek si klade za cíl ukázat možné přístupy k modelování asfaltové kluzné vrstvy v základové konstrukci a stručně shrnout jejich výhody i nevýhody.