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The subject of this paper is the evaluation of the use of waste material, which is the native soil. On the example of the base ground taken from the village of Lipie (Podkarpackie voivodeship), soil-aggregate mixtures were prepared with a different degree of addition of natural aggregate. The study analysed the quantitative and qualitative parameters of the prepared mixtures and assessed their physical and mechanical properties to determine their suitability for the construction of nfrastructural facilities. It should be noted that most specifications recommend the use of primarily aggregate mixtures. The paper presents the results of a study analysing the effect of aggregate admixture to the native soil on selected physical and strength properties of the mixtures developed. The obtained results confirmed the validity of research on the use of soil-aggregate mixtures for construction purposes.

Today, prefabricated concrete elements are used in many construction areas, including in industrial, public, and residential construction; this was confirmed via questionnaire research. In the article, the prospects for precast concrete development are presented, and the factors determining the use of this technology are defined. Based on a review of the literature, it was shown that currently, higher-quality prefabricated elements are primarily created through the implementation of innovative materials and production technologies. For this reason, the lack of research regarding quality control in prefabricated elements based on statistical quality control is particularly noticeable. The quality control process is one of the most important distinguishing features in prefabrication due to the increasingly stringent expectations of customers; it helps to ensure that the desired durability of implemented constructions is achieved. Issues related to assessing the effectiveness of standard procedures presented in this paper were analyzed using statistical methods in the form of OC (operating characteristic) and AOQ (average outgoing quality) curves. Thus, a new approach was proposed because these methods have not been previously used in precast concrete. The shape of the curves obtained confirmed the significant dependence of the value of the acceptance probability on the defectiveness of production. In AQL control systems based on OC and AOQ curves, it is necessary to calculate the current average defectiveness, which should be treated as a basis for the decision to switch from one type of control (normal, tightened, or reduced) to another. In this respect, the standard requirements of quality control have been simplified, and it has not been considered necessary to determine the average defectiveness value in production processes. The examples included in this study, including the analysis of curb production data, clearly show the harmful effects of ignoring the actual process defectiveness. As a result of the calculations, it was found that the average actual defectiveness of the curbs produced could not be equated with batch defectiveness. The analyses carried out in this study prove that equating batch defectiveness with process defectiveness is not an appropriate approach, which was confirmed through the producer’s/customer’s risk analysis. The approach proposed in this study, the analysis of OC and AOQ curves, is an innovative solution in prefabrication and can be an effective tool for managing the quality of prefabricated products, taking into account economic boundary conditions.

The research on obtaining composites based on phenol-formaldehyde resin (PFR) with modified phlogopite quaternary ammonium salt (QAS) reinforced with hybrid glass and basalt fiber was carried out. The influence of the reinforcement structure (glass mesh weave) and the type of fiber on the performance properties of the obtained composites were assessed, especially in terms of their use a grinding wheels reinforced with modified hybrid glass and basalt fiber meshes. Based on the obtained research results, it was found that composites reinforced with a glass fiber layer mesh with a matrix of phenol-formaldehyde resin filled with modified phlogopite are characterized by higher mechanical strength, abrasion resistance and dynamic strength of the disk compared to unmodified composites.

Objects’ measurements often boil down to the determination of changes due to external factors affecting on their structure. The estimation of changes in a tested object, in addition to proper measuring equipment, requires the use of appropriate measuring methods and experimental data result processing methods. This study presents a statement of results of geometrical measurements of a steel cylinder that constitutes the main structural component of the historical weir Czersko Polskie in Bydgoszcz. In the initial stage, the estimation of reliable changes taking place in the cylinder structure involved the selection of measuring points essential for mapping its geometry. Due to the continuous operation of the weir, the points covered only about one-third of the cylinder area. The set of points allowed us to determine the position of the cylinder axis as well as skews and deformations of the cylinder surface. In the next stage, the use of methods based on artificial neural networks allowed us to predict the changes in the tested object. Artificial neural networks have proved to be useful in determining displacements of building structures, particularly hydro-technical objects. The above-mentioned methods supplement classical measurements that create the opportunity for carrying out additional analyses of changes in a spatial position of such structures. The purpose of the tests is to confirm the suitability of artificial neural networks for predicting displacements of building structures, particularly hydro-technical objects.

Technological progress in masonry structures has resulted in the creation of competitive solutions, which force the need for an ever deeper recognition of this type of structure. Masonry is a composite with heterogeneous strength properties. Therefore, the most appropriate way to accurately describe the behavior of the masonry structure under the influence of the working load are experimental research and their statistical and probabilistic analysis. This article presents a series of experimental tests carried out on real masonry structures. The results of the experiments were subjected to static evaluation, determining the most important parameter in the probabilistic analysis—the coefficient of variability of strength. The variability obtained in the experimental studies was used to determine the safety of the structure in the probabilistic method. Achieved values of coefficients of variation and safety coefficients proved to be satisfactory and adequate to the emerging technological progress in the production and embedding of masonry components.

Designing masonry structures or any other structures involves ensuring an adequate level of safety. This is done by applying the appropriate set of partial factor for strength and partial factors for actions in accordance with the recommendations of the Eurocodes. The paper presents an analysis of the reliability of a compressive masonry structure on the example of a wall fragment made of silicate blocks. The relationship between partial factors applied to actions in various configurations and factors for the compressive strength of masonry was investigated. The analyses consisted in determining the reliability index β using the First Order Reliability Method (FORM). The results are presented in diagrams with reference to different construction classes execution of works, as well as different reliability classes from RC1 to RC3.

Poland is characterized by a number of factors which adversely affect the agricultural economy, so this paper will aim to present the possibilities of using multi-criteria decision-making methods of Analytical Hierarchy Process (AHP) in the analysis of the spatial structure of rural areas. AHP is a widely used tool for making complex decisions based on a large number of criteria, such as, for example, land consolidation works on fragmented agricultural land. The first step is to formulate the decision-making process, then the assessment criteria and the solution variants guided by expert knowledge are determined.A ranking, according to which the order of land consolidation and land exchange works in the studied area should be determined, will be defined by using decision-making models of the AHP method. The basis for calculations will be the weights received for the factors/parameters defined for the five thematic groups. Calculations for individual villages will be made, and then the obtained results will allow creating a ranking for the studied commune, allowing for the effective (in terms of economic and socio-economic) spending of funds for this purpose. The presented method can be successfully used to conduct analogous analyses for any area.

BIM (building information modeling) is a kind of technology that has great potential to enhance the level of automation in architecture, engineering, and construction (AEC) projects. The created virtual model of the facility allows coordinating all industries during the entire life cycle of the building. The possibility to save the data related to the given facility in one place, namely in the BIM model, enables control and management of the AEC projects at every stage. During the design and implementation phase, BIM models facilitate the optimization of time, costs, and quality, and in the operational phase, they support effective management of the facility. The use of BIM for building energy modeling (BEM) is the next step of evolution in architecture and engineering design practice. The benefits of using the BIM approach are widely discussed in the literature, however, they may be hard to achieve if appropriate attention is not directed to minimizing the barriers to the implementation of this technology. Observing Europe, one can notice that western and northern countries successfully use BIM for their needs, while the countries of the Eastern Bloc, including Poland, introduce it at a slower pace. In the present paper, the authors conducted a cause-and-effect analysis of the identified barriers to the implementation of BIM technology in the construction process. For this purpose, the authors applied the Ishikawa diagram, which is a tool that helps to recognize the actual or potential causes of failure. The analysis conducted showed that one of the weakest links in the successful BIM implementation is people and, in particular, their lack of knowledge and reluctance to change. The authors indicated the need to introduce and strengthen preventive actions, mainly through education: training, courses, and studies focused on BIM technology.

Intense global urbanization, including spatial planning development, is an essential area that determines sustainable development. It is known that urban development is typically tied to an increase in socioeconomic productivity while also creating considerable inequalities. Despite mounting evidence of intense urban area development, little is known about its consequences on the sustainable development of territories adjacent to said areas. Despite the positive and negative consequences of urbanization and their impact on sustainable development often being highlighted, there is little understanding of and a dearth of analyses on sustainability processes that include spatial planning development. To fill this gap, it must be assessed where sustainable development is actually taking place. Such analyses should not only be confined to the four essential areas: economic development, social development, environmental development, and institutional development, that are tied to sustainable development index calculations. They should also determine the transformations experienced by the areas and factor in a fifth analysis area: spatial planning development. In this paper, detailed data sourced from the Statistics Poland were used to formulate sustainable development indices for urban, rural–urban, and rural communes of the Podkarpackie region of Poland. The data concerned the five areas listed above. Using data standardization and the averaged index method, sustainable development index values were quantified to demonstrate that they displayed various levels of inequalities for the two reference periods of 2015 and 2020. These statistics indicate the key role of spatial planning development in assessing sustainability indices. The findings show that it is not only possible to enhance standard calculation methods to include other data and use them in time and space to create a simple and general quantitative rating of sustainable development, but urbanization can also be factored in that includes spatial planning development. The findings show that a modified computation approach is a reliable and relatively complete index of sustainable development that compensates for the deficiencies of current metrics.

The paper discusses the problems connected with long-term exploitation of reinforced concrete post-tensioned girders. The scale of problems in the world related to the number of cable post-tensioned concrete girders built in the 1950s and still in operation is very large and possibly has very serious consequences. The paper presents an analysis and evaluation of the results of measurements of the deflection and strength and homogeneity of concrete in cable–concrete roof girders of selected industrial halls located in Poland, exploited for over 50 years. On the basis of the results of displacement monitoring in the years 2009–2020, the maximum increments of deflection of the analyzed girders were determined. Non-destructive, destructive, and indirect evaluation methods were used to determine the compressive strength of concrete. Within the framework of the indirect method recommended in standard PN-EN 13791, a procedure was proposed by the authors to modify the so-called base curve for determining compressive strength. Due to the age of the analyzed structural elements, a correction factor for the age of concrete was taken into account in the strength assessment. The typical value of the characteristic compressive strength is within the range 20.3–28.4 MPa. As a result of the conducted tests, the concrete class assumed in the design was not confirmed, and its classification depended on the applied test method. The analyzed girders, in spite of their long-term exploitation, can be still used for years on the condition that regular periodical inspections of their technical condition are carried out. The authors emphasize the necessity for a permanent and cyclic diagnostic process and monitoring of the geometry of girders, as they are expected to operate much longer than was assumed by their designers.

Control of technical parameters obtained by ready-mixed concrete may be carried out at different stages of the development of concrete properties and by different participants involved in the construction investment process. According to the European Standard EN 206 &ldquo, Concrete&ndash, Specification, performance, production and conformity&rdquo, mandatory control of concrete conformity is conducted by the producer during production. As shown by the subject literature, statistical criteria set out in the standard, including the method for concrete quality assessment based on the concept of concrete family, continue to evoke discussions and raise doubts. This justifies seeking alternative methods for concrete quality assessment. This paper presents a novel approach to quality control and classification of concrete based on combining statistical and fuzzy theories as a means of representation of two types of uncertainty: random uncertainty and information uncertainty. In concrete production, a typical situation when fuzzy uncertainty can be taken into consideration is the conformity control of concrete compressive strength, which is conducted to confirm the declared concrete class. The proposed procedure for quality assessment of a concrete batch is based on defining the membership function for the considered concrete classes and establishing the degree of belonging to the considered concrete class. It was found that concrete classification set out by the standard includes too many concrete classes of overlapping probability density distributions, and the proposed solution was to limit the scope of compressive strength to every second class so as to ensure the efficacy of conformity assessment conducted for concrete classes and concrete families. The proposed procedures can lead to two types of decisions: non-fuzzy (crisp) or fuzzy, which point out to possible solutions and their corresponding preferences. The suggested procedure for quality assessment allows to classify a concrete batch in a fuzzy way with the degree of certainty less than or equal to 1. The results obtained confirm the possibility of employing the proposed method for quality assessment in the production process of ready-mixed concrete.

The Miocene deposits of the Carpathian Foredeep are relatively poorly recognized in geotechnical terms. The article analyzes the properties of the Krakowiec clays of the Przemyśl region, in particular physical and deformation parameters. In this part of the Carpathian Foredeep, clay usually occurs at considerable depth under younger Quaternary deposits. Particular attention was paid to the structural characterization of the tested samples. Structural heterogeneity of the studied clay, noticeable already at the stage of macroscopic studies, causes difficulties in conducting laboratory tests of strength parameters, especially the angle of internal friction and cohesion. The specific, layered, claysilt structure may cause difficulties in assessing load-bearing capacity and stability of the ground made of this type of soil. The unusual structure should draw attention of the contractors of geological-engineering and geotechnical documentation and encourage them to check mechanical properties by testing material with direct methods. An important issue is also forecasting changes in strain parameters in relation to the estimation of the effects of settlements of engineering structures.

The main goal of this work is to show the new approach to determining safety technological levels (SLs) in terms of water quality and its chemical stability, as well as issues of water corrosion properties in water distribution systems (WDSs), due to the fact that water supply pipes are prone to corrosion. In the paper the methodology of determining the risk associated with threat to technical infrastructure was considered. The concept was studied on the basis of real operational data from the water treatment plant. The probability of exceeding the individual parameters for WTPI is slightly larger than for WTPII, which means that this water treatment process may cause lack of chemical stability in the water supply network. Operators should anticipate in the process of designing water distribution system, using proper materials, as to ensure an adequate level of safety from the water source to the water recipient. It should be noted that it is necessary to adjust the material of internal installation of water supply networks to the parameters of the water. At present, there are no correlations between the designing step and water parameters. It was concluded that to protect the water supply infrastructure, which belongs to critical infrastructure, water company should put more emphasis on distribution of stable water that has not potentially corrosion properties. Some suggestions were made for the protection of WDS and to ensure safety of system functioning and long-term usability of water pipes.

Series of GNSS receiver tests allowed to determine real accuracy of RTN measurements. Repeated measurements allowed to estimate accuracy in function of used navigation satellite system, duration of measurements and field conditions on measurement site which are related to horizon visibility by obstacles (bushes). Research results indicate no dependency between the technology used and the measurement accuracies obtained and significant impact of the conditions on set-up on the measurement's results.

Urban is one of the three bells in the belfry of St. Trinity Church in Krosno. It is the largest one, with diameter equal to 1,535 mm and it is commonly considered as one of the largest historical bells in Poland. The total mass of all the three bells is close to 4,200 kilograms, so the dynamic actions produced by swinging have a great effect on the supporting structure and on the tower. However, the exact weight of the biggest bell isn't known, and for safety reasons it should be estimated in order to verify the real dynamic forces affecting the structure. The paper describes the method of Urban bell’s survey using terrestrial laser scanning and a total station as a task to estimate its weight by determining its volume.

In recent years, there is an increase of landslide risk observed, which is associated with intensive anthropogenic activities and extreme weather conditions. Appropriate monitoring and proper development of measurements resulting as maps of areas at risk of landslides enables us to estimate the risk in the social and economic aspect. Landslide monitoring in the framework of SOPO project is performed by several methods of measurements: monitoring of surface (GNSS measurement and laser scanning), monitoring in-deepth (inclinometer measurements) and monitoring of the hydrological changes and precipitation (measuring changes in water-table and rainfall).

The main purpose of this study was to obtain information about the actual precision of angle measurements with two instruments (Trimble M3 1 "and South NTS-362R), realizable in given measurement conditions. This object is achieved by using a simplified method of testing instruments contained in the PN-ISO 17123-3 standard [1]. This is a continuation of research described in [2], carried out on the same test base, but this time in a different, less favorable field conditions. The use of the same instrument has created an opportunity to compare and analyze the measurement results. The scope of work includes the measurement and results preparation along with statistical processing of the obtained results for both instruments.

The work presents landslide threats in the context of the planning and spatial planning process. The available sources of information on landslides used for the needs of spatial plating were reviewed and analyzed. Particular attention was paid to the SOPO project - the Anti-slip Shield System. Based on the conducted analyzes, it was found that one of the most important planning problems in the landslide area is the designation of areas for infrastructural investments, including for the development of transport hubs. One of the most effective methods of counteracting and minimizing sludge damage was the properly conducted planning and spatial planning process and risk assessment, among others for road investments.

The article presents a choice of road building technology using the AHP method and the Hellwig method. Based on the analyses carried out with the use of the Saaty and Hellwig methods it was found that the achieved values of ranking for asphalt and concrete pavements are close to each other, which may indicate that both technologies are comparable within the criterions taken for analyses in relation to accepted technological-technical and usability features. When choosing the road building technology one shouldn’t be limited to building costs alone. It’s necessary to consider the costs of 30–40 year exploitation and maintenance of the road. The main task when choosing the road building technology is to build the road of a quality that will enable many years of its exploitation. Based on the analyses carried out with the use of the Hellwig and AHP methods it can be assumed that both technologies. the asphalt one and the concrete one can be competitive because it leads to the progress and development of both of them. Considering the increasing growth of traffic, concrete may be perceived as a technical and economic alternative in comparison to asphalt pavement; which is confirmed in the presented analyses.

Pavements are an essential feature of the urban communication system and provide an efficient means of transportation of goods and services. Depending on its rigidity compared to the subsoil, pavements are classified as flexible, rigid and semi-flexible. The Rigid concrete pavements are now a day becoming more popular in Poland because of reliability construction. Concrete roads are called rigid. The largest advantages to using concrete pavement are in its durability and ability to hold a shape. The conventional methods of rigid pavement Analysis and design are based on the closed-form solutions obtained from the static analysis of infinitely long plates resting on an elastic foundation. In recent years computing programs and probability analysis emerged as a tool which is calculation of capturing pavement reliability. The study of the reliability of RCC pavement on using FReET software was presented. Analysis for reliability have been done using probability and semi probability of RCC pavement.

Most of the construction works carried out on masonry objects are associated with the strengthening of existing elements or assessment of their load capacity to additional load resulting from the change of use. In this situation, the proposed design solutions should always be part of a comprehensive design assessment taking into account the relevant inputs and including information on the actual material properties and the effects of interactions. The use of probabilistic design to evaluate masonry structures enables more economical approach to the issue of possible repairs and reinforcement than the commonly used method of partial factors. In the paper the normalized procedure of semi-probabilistic calculation of load capacity of masonry units and full probabilistic design, recommended in Eurocode 0 [1] are presented and compared. Because of the natural variability of the masonry structures, the information on its real mechanical properties should be obtained from in situ studies. Due to the lack of sufficient number of tests carried out on the masonry structures as well as unknown variation coefficients and distribution parameters, the analyses conducted in the article are limited to basic variables adopted for the probabilistic model based on experimental results described in the literature. The influence of each variable on the reliability index by providing sensitivity coefficients was determined. The basic element of masonry structures such as the lintel masonry was the subject of the analysis.

The failure in longitudinally reinforced concrete beams without transverse reinforcement is the most often observed in a support zone due to bending moment and shear force acting simultaneously in a cross section. This kind of failure is called shear failure and in case of slender beams it can lead to dangerous, brittle damage. Therefore the evaluation of reliability of these members is of the paramount importance, all the most because the design procedure given in Eurocode 2 for shear capacity is of an empirical character. In the paper, the reliability analysis of longitudinally reinforced concrete beams designed according to the rules given in Eurocode 2 was performed. Furthermore, the own experimental investigations were presented. The experiments focused on determining shear capacity and observing the failure process in longitudinally reinforced concrete beams without stirrup of a rectangular and a T-shape cross section. The obtained experimental results were used to calculate the difference of safety margins of the designed shear resistance calculated on the basis of the formula from Eurocode 2 according to reinforced concrete beams without transverse reinforcement of different cross sections.

In recent years, the importance of assessment of structural reliability has increased significantly. This is confirmed by the recommendations of the standard PN-EN 1990 in which the rules and requirements to ensure safety, serviceability and durability of the structure are specified. It also sets out the basis for calculation and verification of constructions and provides guidance to ensure their reliability. Reliability design focuses on the ability to meet specific design requirements, taking into account the planned period of use. The concept of the planned period of use should be considered as the adopted in the project interval in which the structure or a part of the structure is to be used for its intended purpose without the need for general repairs. Typically, reliability is expressed in probabilistic metrics - using an index of reliability or probability of failure. Reliability of building structures depends on a number of correlated factors, mainly on the quality of materials, building precision and level of control, protection against environmental influences and maintenance level during exploitation, specific period of use, adopted solutions for the construction materials, design details and technologies, adopted loads (both their values and combinations), standard requirements regarding capacity, exploitation and durability, quality of computational models used in the design process and methods for assessing reliability of the structure. The performed reliability analysis concerns a reinforced concrete foundation, for which reliability index and probability of failure has been specified using the following methods: analytical method FORM, simulation methods FORM and SORM as well as Monte Carlo simulation.

Statistical conformity criteria for the compressive strength of concrete are a matter of debate. The criteria can have prejudicial effects on construction quality and reliability. Hence, the usefulness of statistical criteria for the small sample size n=3 is questioned. These defects can cause a reduction in the quality of produced concrete and, consequently, too much risk for the recipient (investor). For this reason, the influence of conformity control on the value of the reliability index of concrete and reinforced concrete has been determined. The authors limited their consideration to the recommended standards PN-EN 206-1, PN-EN 1992 and ISO 2394 method of reliability index, which belongs to the analytical methods FORM (First Order Reliability Method). It assumes that the random variables are defined by two parameters of the normal distribution or an equivalent normal: the mean and the standard deviation. The impact of conformity control for n=3 for concrete structures, designed according to the Eurocode 1992, for which the compressive strength of concrete is the capacity dominant parameter (sensitivity factor of dominating resistance parameter according to the FORM is 0.8), has been determined by evaluation of the reliability index.

The probability method of cracking estimation allows for taking all collected information about the properties of construction material, assumed loads and performance precisions into account. The article shows the results of the probability analysis in relation to the reinforcement area of the cylindrical tank walls calculated in tension zone. On the basis of the method proposed in PN-EN 1992-3 and PN-EN 1992-1-1, this reinforcement was calculated due to the uncontrolled development of cracking. The article also presents FEM analysis carried out for the tank using GID and ATENA Static software.

Contemporary trends in development and new material and technical solutions for road pavement should consider the permanent increase in the growth of traffic as well as aspects of environmental protection and balanced development. Nowadays, attempts are made towards estimation of the appropriate thickness for pavement construction already in the phase of its design. Flexible pavements are preferred over rigid concrete roads because of their certain advantages, such as they can be strengthened and improved in stages with the growth of traffic. Flexible pavements are less expensive in regards to their initial cost and maintenance. Concrete pavements are nowadays becoming more popular. The largest advantage for using rigid pavement is its durability and ability to hold its shape against traffic and difficult environmental conditions. Although concrete pavement is less expensive, it requires less maintenance and has a good design life. The main objective of this study is to present a comparative review on the suitability of pavement depending on various parameters such as material, loading, longer life, cost effectiveness etc.