Construction Of Solutions Research Articles

Road Junction Throughput Testing in Transport Logistics—Slovak Case Study

The development of motoring and the ever-increasing traffic load on roads results in congestion and the collapse of traffic in weak places, which, due to their existing construction solution and traffic organization, cannot cover the current and forecasted requirements of carriers. The aim of this article is to present a proposal for a procedure of adjusting the organization of transport, based on our own research and scientific methods of traffic forecasting. The authors work with the hypothesis that there are possibilities of rebuilding weak points in the existing network of overland roads into transport hubs with a higher transport capacity that will cover the requirements of transporters. In this article, the authors emphasize that the basis of the search for an optimal solution to the change in traffic remains the development of calculation methods and consideration of the specific traffic conditions occurring in the given country. Using the example of a case study within the Slovak Republic, we present a proposal for calculation methods based on European standards, which can be used practically without changes in every EU member country. This case study deals with the proposal to transform an uncontrolled four-way intersection into a roundabout. The authors carried out extensive transport research, and on the basis of data analysis, proposed construction and traffic-operational modifications of the existing junction in order to fulfil customer requirements in transport logistics. The proposed solution was verified alternatively with regard to the planned construction of a motorway section near the assessed intersection. When designing the calculation methods, we used our own experimental measurements directly in the area and also included in the calculation methods calculations regarding the capacity of turbo intersections, which are not yet addressed by the technical regulations in the SR environment.

Enhancing geopolymer performance with silane-functionalized graphene oxide: Efflorescence reduction, pore refinement, and improved high-temperature properties

Geopolymer materials offer environmental benefits and strong mechanical properties but face limitations such as efflorescence, shrinkage, thermal stability and poor mechanical performance at high temperatures. This study introduces a novel solution using silane-functionalized graphene oxide nanocomposites (GO-APTS) to address these challenges. Experiments on metakaolin-based geopolymers demonstrate that incorporating GO-APTS improves dispersion, enhances mechanical strength, refines pore structures, and boosts resilience to high temperatures while reducing shrinkage and efflorescence, without compromising the workability of the mixes. Although the structural integrity of the material at nanoscale degrades beyond certain temperatures, the overall thermal resistance is significantly increased, with treated geopolymers displaying a ∼6 % improvement in porosity, ∼20 % higher residual compressive strength and ∼15 % reduction in shrinkage compared to control samples after exposure to heat. Our work reveals the promising potential of silanized graphene oxide nanocomposites in crafting cementitious materials suitable for high-temperature applications, paving the way for their broader use in innovative construction and industry solutions.

Elastic Foundation Solution for the End Notched Flexure (ENF) Mode II Sandwich Configuration

Abstract This paper presents a closed form solution for the energy release rate of face/core debonds in the Mode II end notched flexure (ENF) sandwich configuration. The finite-length sandwich specimen is considered to have a “debonded” region and a “joined” region. In the later, the interface between the top face and the substrate (core and bottom face) is modeled by an elastic foundation, which is a uniform distribution of shear and normal springs. Based on the Timoshenko beam theory, the solution for a general asymmetric sandwich construction is derived. The energy release rate expression is derived via the J-integral. Another closed form expression for the energy release rate is derived from the energy released by a differential spring as the debond propagates. In this closed form solution there is no fitting and everything, including the foundation constants, are given in closed form. Results are produced for a range of face/core stiffness ratios and debond length/core thickness ratios, and are compared with the corresponding ones from a finite element solution. A very good agreement is observed except for small debond lengths vs specimen thickness.

RESILIENCE IN CHANGING POLITICAL AND SOCIAL ENVIRONMENTS: THE GARRI PASTORALISTS IN SOUTHERN FRONTIERS OF ETHIOPIA

While conflict and the resulting damage to livelihoods displacement are commonly seen as socio-economically and politically disruptive, yet it is essential to recognize that they can also present opportunities for social transformation and collective continuity. This study used historical methods to examine how Garri communities cope with recurring displacement and instability. Through historical analysis and interviews, the study explores Garri's resilience in a complex political setting. Garri's ability to handle crises and create stability is influenced by their historical experiences, cultural adaptations, and strategic alliances. Particularly, the Garri shift from reactive to proactive resilience helped them maintain their collective continuity and ontological security. The town-making and commercialized pastoralism highlights their adaptability to uncertainties and proactive response to evolving circumstances. Proactive resilience is irreversible, sequential, autonomous, and result-oriented. Therefore, Garri's resilience mechanisms reveal multifaceted narratives of adaptation, transformation, and strategic response, offering valuable insights into the complex dynamics of survival, living with and adapting to uncertainties, and community rebuilding within a dynamic environment. The study argues that conflict and displacement, despite their hardships, should be viewed as opportunities for collective development and continuity. Communities can achieve ontological security and collective continuity by adopting proactive resilience mechanisms and seeking constructive solutions.

Development of Guidelines for the Design of Cantilevers

Cantilevers are elements typically used in the design of various structures such as factory halls or cantilever cranes. Traditionally, such elements are made of standard profiles or, in the case of large loads, by welding from standard sheets. Often, due to stationary conditions of exploitation, no attention is paid to mass reduction. Increasingly stringent requirements on reducing costs, but also on reducing environmental impact through reducing energy consumption necessary for the production, processing, and transport of materials, facilitate the application of optimization to obtain a construction solution with minimal mass. However, doing so requires advanced high-cost computer tools and increases the required competencies of designers. In this paper, a series of optimizations have been carried out for typical reach and load values of cantilevers aiming to create a database that will facilitate algorithms for selecting cross-sectional dimensions suitable for production using either additive technologies or traditional methods.

Developing heat-conductive concrete with graphite-modified recycled aggregates

This study tackles temperature-induced cracks in contemporary concrete by addressing their low thermal conductivity. Heat-conductive concrete was developed by using graphite-modified recycled coarse aggregates. Through thorough evaluation of coating methods and aggregate types, we enhance thermal conductivity of recycled aggregates by up to 86 % while improving apparent density, water absorption, and crushing value. Employing a one-pot method (Method B) with the graphite to cement ratio of 1:1 establishes an efficient thermal pathway within concrete, resulting in a significant 1.9-fold increase in thermal conductivity without compromising mechanical properties. Advanced imaging techniques and simulations confirm the pivotal role of this pathway in enhancing thermal properties, offering a cost-effective, eco-friendly solution for sustainable construction.

Exploration-Exploitation and Suicidal Behavior in Borderline Personality Disorder and Depression

Clinical theory and behavioral studies suggest that people experiencing suicidal crisis are often unable to find constructive solutions or incorporate useful information into their decisions, resulting in premature convergence on suicide and neglect of better alternatives. However, prior studies of suicidal behavior have not formally examined how individuals resolve the tradeoffs between exploiting familiar options and exploring potentially superior alternatives. To investigate exploration and exploitation in suicidal behavior from the formal perspective of reinforcement learning. Two case-control behavioral studies of exploration-exploitation of a large 1-dimensional continuous space and a 21-day prospective ambulatory study of suicidal ideation were conducted between April 2016 and March 2022. Participants were recruited from inpatient psychiatric units, outpatient clinics, and the community in Pittsburgh, Pennsylvania, and underwent laboratory and ambulatory assessments. Adults diagnosed with borderline personality disorder (BPD) and midlife and late-life major depressive disorder (MDD) were included, with each sample including demographically equated groups with a history of high-lethality suicide attempts, low-lethality suicide attempts, individuals with BPD or MDD but no suicide attempts, and control individuals without psychiatric disorders. The MDD sample also included a subgroup with serious suicidal ideation. Behavioral (model-free and model-derived) indices of exploration and exploitation, suicide attempt lethality (Beck Lethality Scale), and prospectively assessed suicidal ideation. The BPD group included 171 adults (mean [SD] age, 30.55 [9.13] years; 135 [79%] female). The MDD group included 143 adults (mean [SD] age, 62.03 [6.82] years; 81 [57%] female). Across the BPD (χ23 = 50.68; P < .001) and MDD (χ24 = 36.34; P < .001) samples, individuals with high-lethality suicide attempts discovered fewer options than other groups as they were unable to shift away from unrewarded options. In contrast, those with low-lethality attempts were prone to excessive behavioral shifts after rewarded and unrewarded actions. No differences were seen in strategic early exploration or in exploitation. Among 84 participants with BPD in the ambulatory study, 56 reported suicidal ideation. Underexploration also predicted incident suicidal ideation (χ21 = 30.16; P < .001), validating the case-control results prospectively. The findings were robust to confounds, including medication exposure, affective state, and behavioral heterogeneity. The findings suggest that narrow exploration and inability to abandon inferior options are associated with serious suicidal behavior and chronic suicidal thoughts. By contrast, individuals in this study who engaged in low-lethality suicidal behavior displayed a low threshold for taking potentially disadvantageous actions.

Sound Absorption Performance of Ultralight Honeycomb Sandwich Panels Filled with "Network" Fibers-Juncus effusus.

This study investigates lightweight and efficient candidates for sound absorption to address the growing demand for sustainable and eco-friendly materials in noise attenuation. Juncus effusus (JE) is a natural fiber known for its unique three-dimensional network, providing a viable and sustainable filler for enhanced sound absorption in honeycomb panels. Microperforated-panel (MPP) honeycomb absorbers incorporating JE fillers were fabricated and designed, focusing on optimizing the absorber designs by varying JE filler densities, geometrical arrangements, and MPP parameters. At optimal filling densities, the MPP-type honeycomb structures filled with JE fibers achieved high noise reduction coefficients (NRC) of 0.5 and 0.7 at 20 mm and 50 mm thicknesses, respectively. Using an analytical model and an artificial neural network (ANN) model, the sound absorption characteristics of these absorbers were successfully predicted. This study demonstrates the potential of JE fibers in improving noise mitigation strategies across different industries, offering more sustainable and efficient solutions for construction and transportation.

Constructive Challenges in the Water Supply to Cities, from Roman Times to Modern Times. Some Reflections Based on the Portuguese Reality

ABSTRACT Water, as an essential element for life, has always been present in the daily lives of societies. In the case of urban agglomerations, the quantities of water needed to supply them have in some cases been extremely challenging for human abilities, not only in terms of collecting it, but also in terms of transporting it and distributing it for final consumption by the population. Today, the lack of water continues to be a concern, taking centre stage in the global political agenda and in the UN’s 2030 Sustainable Development Goals. Convinced that the lessons of history can help minimise the harmful effects of climate change, the aim of this work is to analyse some of the constructive and architectural solutions found by past societies to obtain water, from which we can learn to preserve and value this important resource. Our approach will focus on analysing cases that refer mainly to the urban landscapes of Portuguese territory, as it is a territory that, in addition to having an occupational history that dates back to ancient prehistory, is characterised by a diversity of river basins and a relief that presents a great variety of forms, but which has nevertheless historically faced various challenges related to the supply of water to its urban centres. Likewise, in order to be able to attest to the fact that the lack of water was a common shortage in the overwhelming majority of urban societies in the past, we will chronologically base our approach between Roman times and the Modern Age, necessarily taking into account the different historical and cultural contexts of the examples presented, as well as the water resources they had, which is why we have structured our presentation in three parts. The first is dedicated to water supply requirements in roman cities, the second to the analysis of continuities and ruptures in the supply of water to the medieval city and third to the main challenges facing modern cities in the field of hydraulic construction. Finally, in the concluding remarks we reflect on the different solutions found, but also on the changes that have occurred in construction solutions, their diffusion and/or rehabilitation throughout history.

Key decision factors of professional stakeholders (architects, engineers, constructors) when deciding for sustainable construction

The built environment and the construction industry account for a significant share of global harmful emissions. Sustainable construction appears to be an effective strategy to achieve a more sustainable society, although it is still not used enough. It is crucial to understand what the main decision factors of those deciding about building practices are. Professional stakeholders such as architects, engineers, constructors, are the ones advising consumers and deciding about construction. An understanding about their decision factors is needed, in order to increase the implementation of sustainable construction. In this study we provide evidence about key decision factors of professional stakeholders in Slovenia when deciding for sustainable construction practices. By conducting an online survey (questionnaire) we identified and analyzed the main drivers and barriers of professionals when making decisions about sustainable construction solutions. With statistical analysis we found out that professional stakeholders included in the survey mostly already had previous experiences working with sustainable construction. They are familiar with sustainable construction concepts. The most important drivers were connected to the factor of occupant health, and the energy-efficiency of the buildings, while the biggest barrier in their decision making is related to higher cost of sustainable construction and lack of awareness. Professional stakeholders are concerned about climate change and their attitudes towards climate change are affecting their decision related to sustainable construction. Respondent provided many comments, clearly indicating that a simple definition of sustainable construction is needed, and more efforts should be done to raise awareness about sustainable construction. Results are contributing valuable information for professional stakeholders, policymakers and other important stakeholders in the construction ecosystem.

Wronskian Representation of the Solutions to the KdV Equation

A method to construct solutions to the Korteweg-de-Vries (KdV) equation in terms of wronskians is given. For this, a particular type of polynomials is considered and we obtain for each positive integer n, rational solutions in terms of determinants of order n. Explicit solutions can be easily constructed and rational solutions from order 1 until order 10 are given.

Using Waste Foundry Sand As Sustainable Construction Material

India's rapid industrialization and urbanization have led to substantial waste generation, posing significant environmental challenges. Among these wastes, the byproducts of metal industries, such as waste foundry sand (WFS), offer potential solutions for sustainable construction. This study investigates the feasibility of using WFS as a partial replacement for fine aggregate in M20 grade concrete. The experimental program involved incorporating WFS at varying percentages (0%, 10%, 20%, 30%, 40%, and 50% by weight) and assessing the impact on the compressive strength of concrete, complemented by the addition of a plasticizer (1% by weight of cement). The results demonstrated that up to 20% replacement of fine aggregate with WFS significantly enhances the compressive strength of concrete, achieving increases of 40.4% and 56.5% for 7 and 28 days of curing, respectively. Beyond 20% replacement, the compressive strength declined. This research highlights the potential for utilizing industrial waste in concrete production, promoting sustainable construction practices by reducing the reliance on natural resources and addressing waste management challenges.

Study of the causes of the collapse of a high-rise chimney under conditions of long-term operation

This article analyzes the causes of the collapse of a high-rise chimney in Petropavlovsk. A study of the factors of long-term (over 60 years) operation of a high-altitude (H=150 m) chimney was carried out. The analysis of the constructive solution of the pipe was carried out, and the study of the operating conditions was performed. To theoretically assess the technical condition and stress-strain state factors (SSS) of the collapsed chimney, automated verification calculations were carried out based on the actual parameters and characteristics obtained during the last technical inspection. An automated verification calculation of SSS factors determining the bearing capacity of an object (its strength, rigidity, reliability, and durability) has been performed. Theoretically, the physical wear of the object has also been carried out. Based on the study of the available technical documentation and conducting a continuous, detailed instrumental examination of the facility, the expert organization established the significant causes that led to the pipe accident.

Assessment of Dynamic States of Railway Vehicles: Structural Mathematical Modeling

Introduction. The speed rise of railway transport and an increase in the loads on the axles of wheelsets necessitate the modernization of the existing fleet. Scientific studies in the field of rolling stock dynamics are aimed at taking into account the oscillatory processes that occur during the movement of railway vehicles in a traditional design. The attachment of supplementary elements was considered at the coupling level of two cars and the attachment of a third trolley in the center of gravity of the railway platform. The scientific literature has not paid enough attention to the construction of mathematical models that make it possible to assess the dynamic states of such constructive solutions. The objective of this study is to create a method for evaluating the dynamic conditions of a car. The situation is considered when an additional set of mass-inertial and elastic elements is introduced into its structure, and the general dynamic condition of the vehicle depends on the adjustment of their parameters.Materials and Methods. The basic research tool is the structural mathematical modeling, which is based on an approach where the source design scheme is a mechanical oscillatory system in the form of a solid body on elastic supports with supplementary typical elements introduced into its structure. The dynamic analogue of the calculation scheme used is the block diagram of the automatic control system, the use of which provides detailing the connections between typical elastic and mass-inertia elements.Results. A method for estimating the dynamic states of railway vehicles is proposed. It is based on the construction of mathematical models, taking into account the introduction of an additional structure of mass-inertia and elastic elements. The impact of additional parameters on the dynamic condition of the vehicle is investigated. Analytical relations have been obtained that provide reducing the dynamic loads on the major structural elastic elements when changing the corresponding parameters of a technical object. The transfer function of interpartial relations is given, which provides controlling the interaction between the coordinates of the vehicle movement under the action of two kinematic disturbances of the in-phase type.Discussion and Conclusion. The generated mathematical model provides for assessment, monitoring and control of the dynamic state of the vehicle under conditions of kinematic disturbances. The research results can be used to modernize existing vehicles and create new ones with improved dynamics.

Semi‐implicit method of high‐index saddle dynamics and application to construct solution landscape

AbstractWe analyze the semi‐implicit scheme of high‐index saddle dynamics, which provides a powerful numerical method for finding the any‐index saddle points and constructing the solution landscape. Compared with the explicit schemes of saddle dynamics, the semi‐implicit discretization relaxes the step size and accelerates the convergence, but the corresponding numerical analysis encounters new difficulties compared to the explicit scheme. Specifically, the orthonormal property of the eigenvectors at each time step could not be fully employed due to the semi‐implicit treatment, and computations of the eigenvectors are coupled with the orthonormalization procedure, which further complicates the numerical analysis. We address these issues to prove error estimates of the semi‐implicit scheme via, for example, technical splittings and multi‐variable circulating induction procedure. We further analyze the convergence rate of the generalized minimum residual solver for solving the semi‐implicit system. Extensive numerical experiments are carried out to substantiate the efficiency and accuracy of the semi‐implicit scheme in constructing solution landscapes of complex systems.

The Development of Quinoxaline-Based Electron Acceptors for High Performance Organic Solar Cells.

In the recent advances of organic solar cells (OSCs), quinoxaline (Qx)-based nonfullerene acceptors (QxNFAs) have attracted lots of attention and enabled the recorded power conversion efficiency approaching 20%. As an excellent electron-withdrawing unit, Qx possesses advantages of many modifiable sites, wide absorption range, low reorganization energy, and so on. To develop promising QxNFAs to further enhance the photovoltaic performance of OSCs, it is necessary to systematically summarize the QxNFAs reported so far. In this review, all the focused QxNFAs are classified into five categories as following: SM-Qx, YQx, fused-YQx, giant-YQx, and polymer-Qx according to the molecular skeletons. The molecular design concepts, relationships between the molecular structure and optoelectronic properties, intrinsic mechanisms of device performance are discussed in detail. At the end, the advantages of this kind of materials are summed up, the molecular develop direction is prospected, the challenges faced by QxNFAs are given, and constructive solutions to the existing problems are advised. Overall, this review presents unique viewpoints to conquer the challenge of QxNFAs and thus boost OSCs development further toward commercial applications.

EXPERIMENTAL DETERMINATION OF FLOOR PANELS DEFORMABILITY OF A LARGE-PANEL SYSTEM BUILDING AFTER RENOVATION

This paper deals with a field tests of prefabricated reinforced concrete floor panels of a multistory building by the method of hydrostatic loading. Object of study is presented by 3 damaged floor slabs of a 9-storey residential building which was hit during the russian invasion. After renovation of panels using the constructive solution which consists of a reinforced build-up layer in the compressed zone (upper part) and additional external reinforcement in the stretched zone (lower part) connected to each other with the help of anchor connections, a series of tests with water loading were set. For creation of loading an inventory pool was used, which was gradually filled with water at a step of 1kN/m2. Maximum created loading level was 5kN/m2 which corresponds to the operational load. After reaching the maximum load, the panels were left under load for 15 hours and then fully unloaded in steps of 1kN/m2. For each panel two type of tests were established: first when panel had both upper and lower part of reinforcement, and second – when lower reinforcement within steel beams was removed. The idea of dismantling of steel beams connected with previously performed numerical analysis which gave to little difference in deflections of panels for these two cases. Deflection measurements at critical locations along with thorough visual inspection were conducted during the loading and unloading cycles. No damage was observed during the in-situ loading and unloading cycles. Maximum vertical deflection for panel before dismantling of beams lies in the diapason of 1.95-2.1mm and 2.31-2.4mm after they were removed. These results meet the requirements of regulatory restrictions on the maximum deflection equal to 20 mm for this structure. Difference in deflection for two cases doesn’t exceed 20% which allows to abandon the use of lower reinforcement in the form of steel beams in the future. As the size of the pool doesn’t cover the whole panel area, the equivalent uniformly distributed load was also calculated using Lira software. Keywords. Large panel system house, reinforcement, floor panel, method of hydrostatic loading, deflection.

THE PHILOSOPHY OF FRATERNITY AND THE FOUNDATIONS OF MORAL SOLIDARITY

Analyzing the historical forms of moral solidarity, one of which is the phenomenon of fraternity and trying to see in this form the foundations of constructive cooperation in modern conditions, we should pay close attention to the underestimated conceptual provisions and mechanisms. We believe that these factors play an important role in overcoming disintegration processes, both at the level of social communication and at the level of the mental foundations of intercultural and intercivilizational communication. The article is devoted to the philosophical foundations of the phenomenon of fraternity, mainly based on the material of European and domestic socio-philosophical reflection. The relevance of this topic is determined by the fact that the current international situation presents new challenges and that Russia is looking for constructive solutions to complex contradictions that have arisen in the international community. On the other hand, the axiological foundations of Russian civilization, which have been its genetic basis for many centuries, require constant philosophical reflection. The article discusses the essential importance of the phenomenon of fraternity for overcoming social disharmony, clarifies the advantages of this form of social interaction over formal cooperation. The methodology of the work is based on a socio-philosophical analysis of the axiological and ethical foundations of various forms of joint human activity. The article attempts to identify the structure-forming foundations of the system of social relations by the example of the phenomenon of fraternity.

Architectural Features of Churches in the Kaštela Coastal Area between 1492 and 1918

This paper aims to synthesize recent knowledge about the churches built between 1492 and 1918 in the Kaštela area and present its characteristics obtained by research in the doctoral thesis of the first author. The research covered 18 churches located in the coastal area. Fourteen churches have been preserved, two were pulled down, while the existence of two other churches was detected on old maps and in written documents. After a genealogical and catalogue study, a typological and stylistic analysis of the churches has been made. The longitudinal aisleless churches as a dominant shape vary in dimensions, type of construction, construction solutions and elements of architectural decoration.

Linking energy efficiency and waste recovery to improve housing insulation and tackle energy poverty in south-central Chile

Given the environmental impact of the construction industry, sustainable solutions are increasingly needed to minimize the life cycle impacts of buildings by means of reusing renewable industrial waste. Abundant forest and farm waste exist in center-south Chile, with great potential to be used as thermal insulation and, thus, improve the livability of houses located in an area facing air pollution and energy poverty issues. This paper discusses two types of insulation produced and tested jointly with Germany-based Fraunhofer Institute for Wood Research (WKI)– using Chilean agroforestry waste: First, a flakeboard made of wood veneer chips; and second, a flexible substrate and a pressure resistant board made of wheat and oat straw. The main goal of this research is to assess, by means of digital modeling and experimental tests, the thermal characteristics and the resistance to humidity of these new insulation materials and their performance within construction solutions usually used in Chile. The benchmarks used were the most demanding national residential energy efficiency standard implemented to address air pollution and energy poverty, and the most demanding international standard, both for walls and roofing. The results of both insulation materials was promising, as they met the thermal performance and resistance to humidity requirements and show technical feasibility for the insulation market; in addition, they share the potential to be used in different types of buildings and construction solutions both in Chile and abroad, promoting a sustainable approach starting from the raw materials and the manufacturing process, through the buildings’ operations.