Ana Kontić

This paper presents the application of Partial Least Squares (PLS) regression for optimizing mortar compositions with the aim of achieving a balance between mechanical performance and environmental impact. Mortars containing pozzolanic additives (metakaolin, zeolite) and recycled materials were tested, with variations in cement and water content. The chemical characterization of raw materials was performed using energy-dispersive X-ray fluorescence (EDXRF) and inductively coupled plasma optical emission spectrometry (ICP-OES), enabling insight into the content of key oxides (SiO 2, Al 2O 3) that influence pozzolanic activity. Based on experimental data regarding mortar composition and compressive strength, as well as calculated CO₂ emissions per unit volume, a PLS model was constructed to quantify the influence of individual components on the target properties. The results showed that specific proportions of metakaolin and zeolite can contribute to the reduction of CO 2 emissions without a significant compromise in mechanical performance. Furthermore, the use of recycled concrete as a partial replacement for natural aggregate enables more efficient resource utilization and a reduction in construction waste, without impairing key properties of the mortar. The proposed model represents a tool for the efficient design of environmentally optimized mortar formulations, with strong potential for further application in engineering practice and the construction materials industry.

The paper is focused on the analysis of the spatial, morphological and symbolic characteristics of the Slobodište Memorial Park, starting from the assumption that the artistic-quantitative determination and expression, as well as the materialization of the fundamental representations and expressions of this memorial park, is important for conveying its basic meanings and messages. In the first part of the paper, a brief historical review of the formation of the memorial in the Kruševac region is given, as well as the context of the construction of Slobodište Memorial Park. The focus of the work is on the analysis of the Memorial Park, from the urban determination of the space, through the analysis of individual compositional units and elements, in the light of their spatial, morphological and symbolic characteristics. In the third part of the paper an overview of Slobodište in the light of its connection to the city of Kruševac and its residents. The paper aims to examine the thesis that the primary ideological motto of Slobodište is embodied in the synthesis of architecturalurbanistic, sculptural, as well as literary achievements, and that as such it can be inspiring and instructive for further research of memorial architecture.

Physical, mechanical and carbonation progress properties of air lime mortars, formulated with the addition of air entrainers, were analyzed, aiming to investigate the influence of air entrainers on abovementioned properties of lime-based products. Samples were cured in two curing conditions and their properties were evaluated after 14, 28, 60 and 90 days. The results obtained revealed that the addition of air entrainers influences the change in dynamics between drying and carbonation processes, therefore influencing the rate of carbonation process. This observation was reflected in carbonation progress as well as physical and mechanical properties of the tested samples.

The importance of masonry arch bridges as a traffic network element calls for a thorough analysis focused on both structural stability and loading capacity of these historical structures, considering the usage of these bridges in contemporary traffic conditions. This paper focuses on the analysis of longitudinal cracks in a single span masonry arch bridge to evaluate its influence on structural behaviour of the system. As longitudinal cracks do not necessarily present an inevitable collapse mechanism, analysis of the causes is crucial for evaluating the serviceability and functionality of the bridge investigated. The methodology is based on the following: literature review, observation of the stone bridge in Ivanjica, geological testing of the site, geophysical testing of the bridge, laboratory testing of mechanical characteristics of stone used for the bridge construction and biological analysis of the samples of implemented materials on the bridge. Finite element analysis of the bridge was conducted to define the causes of the longitudinal cracks. The 3D simulation model was based on the data collected through observation and experimental analysis. This paper provides extensive research on a single span masonry bridge, examining how different deterioration mechanisms, in conjunction, can lead to the appearance of cracks in masonry arch bridges and provide remedial measures accordingly.

Protecting the built cultural heritage is one of the most important tasks in architectural practice. The process of repair is time-consuming, weather-dependent, and sensitive to materials applied. Introducing new materials in historic building repair in order to decrease the time needed for repair, brings some risk in the preservation process. The most common material for masonry repair is lime mortar. Adding cement to lime mortar can improve the mechanical properties of mortar and speed up the repair process. The high amount of cement may increase the strength, but decrease ductility and permeability of mortar, causing damages to protected buildings. An increase in strength with the smallest amounts of cement demands optimization of water content in the mixture. Tests were performed to investigate the influence of the water/binder (w/b = water/(lime + cement) ratio on mortar strength and water permeability. An air-entraining agent (AEG) was introduced to improve permeability. Results confirmed that adding small amounts of cement to lime (20% by weight) and decreasing of w/b ratio, improves the strength, with almost negligible influence on water permeability. The addition of very small amounts of AEG did not decrease the strength, nor the permeability.

The paper presents an overview of the results based on the integration of traditional (analogue) and instrumental (digital) methods of heritage surveying. The thematic framework was stimulated by participation at the professional workshop in Lizori, in Italy, held in June 2018.. This specific methodological framework of integrated research, uses different tools, in the function of morphological specifications of different parts of a historical building. The very nature of architectural heritage requires the integration of different methods in order to achieve an adequate level of accuracy. The project of digitization of the Lizori village aims to present, on the one hand, an almost unknown historical heritage through multimedia presentation, and on the other hand, set up an information tool for restoration, maintenance and valorization.