CO₂ emission limits introduced by the European Union are encouraging works on new-generation materials with reduced clinker content. Currently, fumed silica from hard coal combustion is used in cement and concrete technology in Europe and Poland. Its wide application depends mainly on its chemical and phase composition, especially the reactivity of pozzolanic acids and its high fineness similar to cement Many authors studied the influence of fly ashes from hard coal combustion, in accordance with PN-EN 450-1 and 450-2, on the properties of concrete, including the course of the carbonation process. There are no studies in the literature involving ashes from sewage sludge. The objective of the research is to assess the course of carbonation of concrete produced on the basis of fly ash from the thermal transformation of sewage sludge over time and to describe this phenomenon in a mathematical form. An additional objective was to analyze the physicochemical composition of sludge ash in accordance with the requirements of EN 450-1, ASTM-C618-03. In addition, this study also demonstrated the possibility of producing fly ash-modified standard concrete through the thermal treatment of sewage sludge. The average compressive strengths of Krakow gray concrete after curing for 28, 56, 90, and 365 days were 50.1 MPa, 50.6 MPa, 50.8 MPa, and 61.9 MPa, respectively. On the one hand, the additives introduced in the concrete mixture accelerate the carbonation process by shifting the carbonation front deep into the concrete and, on the other hand, create a denser microstructure In all cases, the largest increase in carbonation depth was observed up to the 56th day of the study, while the smallest increase was observed between 90 and 180 days. The diffusivity decreases and the rate of carbonation is reduced. The determined regression coefficients of hyperbolic models indicate the proper adjustment of the adopted hyperbolic model to the results of laboratory tests under accelerated carbonation conditions (R = 0.85–0.99), regardless of the content of fly ash from sewage sludge in ordinary concrete samples.

Reinforced masonry constructions and their elements must meet strength and stability requirements. These conditions determine wall structure safety during construction and operation. Safety depends on diagnostically aimed tests that check the objects’ quality or locate damages to structural elements that arise during operation. This article is focused on the experimental modal analysis research of reinforcement ceramic masonry elements. The aim of the research was to check whether it is possible to observe the damage in reinforced masonry structures and the accompanying vibration of signal transition functions by conducting pilot studies and using different types of reinforcements. The experiment was conducted on three samples of various types of reinforced brick walls. During the vibration tests, the segments were subjected to various loads, and it was observed how the increasing cracks and damage changed the courses of the measured functions of the vibration process, reflecting the damage to the segments. This made it possible to assess the variability of the vibration characteristics of the tested reinforced wall elements and the usefulness of the applied test method. The aim of the study was to check the assessed effectiveness by testing the degradation of the reinforced wall elements. The research confirmed the usefulness of the SISO methodology in identifying damages, which has been implemented in selected precast factories in Poland.

The presented considerations cover selected issues from the area of ​​using information technology in the design and operation of technical objects. The essence of computer integration of individual tools that make up the production of a safe product is presented and selected computer-aided systems for maintaining the serviceability of objects are discussed. Examples of computer tools and procedures supporting safe operation are given, especially when using technical diagnostic methods. The indicated statistical procedures are particularly important in research on objects, where the multidimensionality of diagnostic signals requires the wide use of various statistical procedures at the processing and decision-making stages. For these tasks, the capabilities of the MATLAB program for determining the symptom matrix, software tools for reading and exporting files to the .unv format, the OPTIMUM method computer algorithm, the computer analysis of decomposition (SVD) algorithm and the program for analyzing the state matrix using the MAC theory are presented.

Anthropogenic impacts refer to environmental changes caused by or under the influence of humans, directly or indirectly. The article highlights the issue of technical diagnostics and presents selected problems related to the automation of procedures for assessing the degree of degradation of technical objects. The possibilities of using vibration methods with particular emphasis on condition forecasting are indicated. Current knowledge of these problems is insufficient and requires further research on data processing, analysis of the effectiveness of diagnostic and prognostic procedures, collection and selection of diagnostic parameters and development of automatic procedures for assessing, recognizing and forecasting the condition of technical objects. New solutions and various aspects of diagnostic forecasting based on the proposed partial procedures focus on factors determining the automation of procedures for identifying the states of technical systems. New automated procedures for acquiring and processing symptoms indicating changes in the state of objects provide better possibilities for control and supervision over the operation and maintenance of technical systems by identifying their current states and good forecasting. This is possible thanks to the use of many original solutions in the field of automation, including methods and procedures for computer-aided research, modeling the degree of degradation of engineering objects, decision-making support systems, classification and standardization.