The paper presents a new perspective on the issues of life cycle assessment (LCA) and durability analysis of structures. In the case study, a comparative analysis of three variants of the chosen structure was performed. Subsequently the durability of all variants was assessed. The structural solutions were modified to achieve a targeted life cycle for all variants. Modified structures were evaluated in LCA. The study points to the fact that orthodox compliance with code prescriptions can lead to an uneconomical and unsustainable solution and suggests an approach where the design of the structure is adjusted for the required service life.

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The environmental aspects of sustainable development in the construction industry consist in the utilization of secondary raw materials in a design and construction of new structures. The fact that China significantly reduced the import of plastic waste in 2017 raises the question of dealing with this waste in other states. A complicated recycling process of waste plastics puts pressure on scientific community to find new, more efficient ways of using this waste. The paper deals with the behaviour and mechanical properties of a completely innovative material called waste plastic-based concrete composed of natural aggregate and plastic waste which replaces cement as a binder. The completely unique composition of this concrete required to firstly test production technology and subsequently to conduct standard quasi-static experimental tests to obtain basic knowledge about the behaviour and mechanical properties of this composite. The obtained knowledge show that special attention must be paid to the production of the material which takes place under elevated temperature. The investigated composite has a relatively high tensile strength compared to conventional concrete and brittle fracture behaviour. In the next phases of the research the optimization of the production technologies and the composition of the composite will be provided.

A big progress has been made in decrease of environmental impacts of cement production. Dust pollution around cement plants has been considerably decreased thanks to efficient dust separators. An intention of further emission reduction has been announced. The environmental burden of cement production is also decreased by substitution of cement by alternative binders. Hydraulic properties of energy by-products have been investigated for a long time to check their potential as a partial substitution of traditional cement binder. The paper will focus in examining the influence of variation of the concrete composition on the environmental impacts, identification of the most severe procedures in the cement production and analysis of meaningfulness of implementation of the proposed measures. The environment is a complex system. Potential modifications of concrete composition or production technology may bring benefits in certain areas and on the contrary cause environmental harm from another perspective. Hence, analysis of the cement production impacts cannot be based on one aspect, and a broad portfolio of impact categories will be assessed regarding concrete production environmental burden.

One of the sustainability aspects of the construction is a sufficient durability. In objectively justified cases, the durability is enhanced by reconstruction. To ensure economic design of the reconstruction, non-liner approaches are often applied. This paper deals with aănonlinear numerical simulation of disassembled reinforced concrete (RC) panels strengthened by an ultra-high performance concrete (UHPC) layer. Based on the prior experimental programme, simulations of four-point bending tests of the original and strengthened panels are created using software ATENA Science. Calibration of the material parameters is based on the destructive and non-destructive investigations performed in the experimental programme. The comparison of the experimental and numerical model loading curves indicates that additional mechanical testing will be needed in order to achieve an accurate numerical simulation. Although the bending test of the RC panel and the crack mouth opening displacement (CMOD) test performed on the applied UHPC beam were calibrated, the final model of the UHPC strengthened panel does not correspond completely with the experimental measurements. In this paper the possible reasons for this result are discussed.