Archives of Civil Engineering, a quarterly journal of the Polish Academy of Sciences (“Committee for Civil and Water Engineering”) and Warsaw University of Technology (“Faculty of Civil Engineering), publishes, exclusively in English, original scientific articles of a theoretical, experimental, numerical, and practical nature. These can include research and review papers, as well as case studies, from all branches of Civil Engineering. The main fields of our interest are related to structural mechanics, soil mechanics, foundations, brick, concrete, timber, steel, glass, and composite polymer structures, hydro-technical objects, bridges, rail and road structures, building physics, construction management, building materials, transportation, land surveying, building services, and the education of civil engineers. With a long history dating back to 1954, the periodical is available in both electronic and traditional versions. The maximum number of papers per volume is 40. We proudly obtained a score of 100 points from the Ministry of Science and Academic Education. The journal website is being gradually updated as part of the migration from journals.pan.pl. The information on this page is current.
Warsaw University of Technology Faculty of Civil Engineering and Committee for Civil Engineering Polish Academy of Sciences
Exploration and research on reform and practice of graduation design for civil engineering major based on BIM technology and OBE concept
With the continuous development and progress of the construction industry, the requirements for civil engineering professionals are also increasing daily. Building a high-quality ability training model is the top priority in educational reform and development. As an important part of undergraduate teaching in civil engineering, graduation design plays a vital role in cultivating students' comprehensive abilities and innovative spirit. This research combined BIM technology with the OBE concept to conduct reform and practical research on graduation design for civil engineering majors. By analyzing the problems existing in the current graduation design of civil engineering majors, the advantages of BIM technology and the OBE concept and the necessity of combining the two were elaborated. This paper introduced in detail the graduation design reform plan based on BIM technology and the OBE concept, including reform measures in aspects such as design content, guidance methods, and evaluation system. Through actual case analysis and questionnaire survey, the effectiveness of the reform plan was verified and future development was prospected.
Copyright (c) 2026 Archives of Civil Engineering https://creativecommons.org/licenses/by-nc-nd/4.0
Influence of a glass fiber mesh on pre-damaged flexible pavement’s fatigue
As part of a rehabilitation process, one lane of the pavement was reinforced with glass fiber mesh placed beneath the asphalt layer, while the other lane underwent rehabilitation without the mesh. To evaluate the performance of the pavement, the researchers used Falling Weight Deflectometer (FWD) measurements to assess the layer modulus, which is critical for understanding the structural capacity of the pavement. The fatigue life of the pavement was then calculated and compared against both the measured and predicted traffic load. The results indicated that the application of glass fiber mesh reinforcement positively impacted the pavement’s structural integrity and durability. However, the beneficial effects were only observed after the mining activities that had initially caused damage to the pavement ceased. The pavement’s fatigue life, based on dynamic load and traffic conditions, was compared between reinforced and unreinforced lanes, showing that the reinforced lane exhibited better resistance to damage once mining influences had concluded.
Pre-stressed concrete railway sleepers type B70W-60: requirements, technology of production, numerical modelling and calculations of immediate technological shortening
A railway sleeper is one of the basic elements of track that directly impacts traffic safety. Therefore is essential a high quality requirements for the sleepers. This thesis shortly demonstrate requirements for prestressed concrete railway sleeper and present production technology and the method of prestressing of sleeper B70W-60. Goal of this paper covers the numerical modelling of the sleeper and determination of immediate strain and shortening directly after prestress activation. Longitudinal shortening the sleeper immediately after releasing tension bolts, manifest itself in separating concrete from mould walls. Measuring the width of this separation is a useful indicator value – if it is too high, it may mean that there are technological process errors or an internal defect of an individual sleeper. Therefore, the numerical estimation of the separation width is a part of design process.
Development of a risk map, a risk allocation matrix, and a risk assessment matrix for the energy construction sector
This article presents an integrated framework for developing risk management tools tailored to energy construction projects. It advocates for a transition from traditional reactive methods toward a proactive, engineering-led approach. The study examines the systematic development and synergistic application of three distinct tools: risk maps, risk allocation matrices, and risk assessment matrices, evaluating their collective impact on key project parameters such as cost, schedule, scope, and quality. Central to the research is a multi-dimensional analysis of sector-specific risk determinants, ranging from macroeconomic volatility and regulatory shifts to the complex technical interdependencies inherent in high-voltage infrastructure. Grounded in the contractual frameworks of the “Code of Good Practices for the Energy Industry” (PZPB) and “Standards for Investment Execution” (SIDiR), and bolstered by empirical research conducted between 2022-2025 regarding contractor claims in 35 national electric power projects, the article develops practical, validated tools for comprehensive risk management.
Trends and features in sustainable construction materials; a global review
Building construction projects are one of the major consumers of natural resources, causing resource depletion and the emission of environmental pollution. The sustainability parameters in construction are shifting the paradigm of traditional construction towards a more sustainable construction. Sustainable construction materials are designed and aligned to enhance structural durability, prevent exhaustion of natural resources, improve energy efficiency, lower harmful emissions, and enrich indoor air quality. The objective of this study is to explore the core features which drive sustainable construction materials in the building construction industry; to analyze current trends and preferences being made, and the advancement and challenges encountered in different regions worldwide. A comprehensive literature review approach is utilized to collect and synthesize data from a wide range of resources. The study includes research articles from 2014 till 2024 published in USA, Europe, and Asian countries, using search engine scopus, web of science, and google scholar, which discuss the environmental, social, and economic parameters of sustainable construction materials while excluding articles focusing exclusively on the non-construction industry. The literature review compares trends in sustainable construction materials, featuring different regions of the word. The review has identified several key features and trends shaping the construction industry towards a more sustainable construction world. It also provides a road map for industry players interested in incorporating green materials in construction works.
Fire safety in railway and metro tunnels
The article presents the development of tunnel infrastructure in the world. Then, the hazards occurring in fires occurring in underground rail transport are characterized and several incidents that have occurred are described. It is also noted that a large role in improving fire safety in tunnels is played by conclusions drawn from experience from incidents that have occurred and by predicting new threats and possibilities of preventing them. Despite equipping tunnels with increasingly modern safety systems, fires, accidents and disasters still occur, as is shown by the given number of fires in tunnels in German-speaking countries that occurred in the years 2013–2023. In addition, the article discusses the current EU requirements aimed at ensuring an optimal level of safety in tunnels in the most economical way. They were developed taking into account scenarios of the most probable events. Ensuring that residual risk is reduced to a low level requires combining all safety layers in the following order: prevention, mitigation, evacuation and rescue. It was also emphasized that the proper selection of non-metallic materials for the construction and equipment of rolling stock and tunnel infrastructure is an important element of effective fire protection. Nevertheless, the required systematic inspections of the condition of vehicle and tunnel equipment, as well as rescue operations exercises according to various scenarios provided for in the Tunnel Emergency Plan, play an important role.
Deep excavation wall design using reinforcement learning
This study investigates the application of reinforcement learning (RL) for obtaining near-optimal designs of diaphragm walls in geotechnical engineering. A physics-based numerical environment is developed to simulate soil–structure interaction, relying on a Winkler spring formulation with pressure-dependent soil springs to approximate the nonlinear response of the ground. This modelling framework allows the agent to evaluate candidate designs through physically meaningful structural responses rather than surrogate performance indicators. To reflect realistic engineering practice, a specifically designed action space and reward function are formulated, incorporating both discrete design decisions and continuous geometric parameters. During training, the agent iteratively proposes a design configuration, observes the response computed by the physical simulator, and updates its policy based on the resulting reward signal. Several common RL algorithms are investigated, including Proximal Policy Optimization (PPO), REINFORCE, and the Parameterized Deep Q-Network (P-DQN), enabling a comparative assessment of policy-based and hybrid value based approaches for this task. The algorithms are evaluated in terms of learning stability, convergence behaviour, and the quality of the resulting design solutions. The results demonstrate the potential of RL-based methods to explore complex design spaces efficiently while respecting physical constraints, highlighting their suitability for supporting automated or decision-assisted design of diaphragm walls.
Determining the duration of a construction project using Markov chain
In this article, practical application of the Markov chain to estimate the timeframe of a construction project is proposed. This methodology involves forecasting the duration of work based on the probability of transitions between different states in the implementation of the construction project. In this context, each state can represent a specific phase of the construction work, such as the different condition during construction work with or without risks. Transition probabilities between these states can be determined based on statistical data from previous projects, expert opinions, and other sources. In this article, the transition probabilities between states were established based on expert opinions. The proposed approach allows predicting the likely completion time of the project and assessing the impact of multiple elements on the project's timeframe on its duration. The article also includes numerical examples illustrating the operation of the proposed approach. The obtained results demonstrate the practical application possibilities in terms of efficient planning of a construction project considering risk factors.
Experimental study on post fire mechanical properties exhibited by S235JR and S355J2+N steel grades
The results of research on mechanical properties exhibited by typical structural steel grades S235 and S355 are presented in this paper. Each time the samples had been heated up to a predetermined temperature, cooled and subjected to a static tensile strength test. Several fire development scenarios and sample cooling scenarios had been considered. The maximum heating temperature reached during the research remained between 400◦C and 800◦C. The results of own experimental research have been compared against the recommendations found in bibliography regarding the reduction degree of mechanical properties exhibited by steel. The changes in the values of such parameters as the yield limit, tensile strength, modulus of elasticity and total limit elongation have been considered in the conducted analyses. Based on the results of this research new, temperature dependent, values of reduction coefficients for mechanical parameters of steel exhibited post fire have been determined. Two computational approaches have been applied for this purpose. In the first approach the reduction coefficients have been determined based on the minimum values obtained experimentally. In the second approach the characteristic and design values have been derived following the recommendations of the standard PN EN 1990. Both proposed sets of reduction coefficients may be applied when assessing the technical condition of a structure following a fire incident.
Different configurations of the non-minimal tensegrity triplex
The paper presents analyses on stable prestressed configurations of the tensegrity triplex with a non-minimal number of members. The non-minimal triplex is generally understood in the literature as the minimal triplex with three additional cables. However, this research shows that many different configurations can be obtained during prestressing. The prestressing procedure is led by changing the lengths of selected groups of members, i.e., struts, horizontal cables, cross cables, or additional members, assuming symmetry. A different view on prestressing is presented, where typically understood tensegrity natural configuration is separated into a newly called geometrical configuration and natural lengths of attached members. The presented interpretation of prestressing has a clear physical meaning. The calculations are based on the elastic energy approach, which is used to write the nonlinear equations that are afterward solved numerically. Two examples of prestressing the non-minimal triplex are presented, for slender and stocky prisms dimensions. The results show that additional members usually understood in the literature as additional cables, can as well serve as struts, which leads to a new group of structures with tensegrity features.
Study on the close distance perforation capabilities of explosively formed penetrators
The paper presents a study of the perforation capabilities of Explosively Formed Penetrators (EFP) at small distances between the charge placement and a target for the selected charge configurations. The specific design of the warhead is considered, where the casing is made of light, low-strength material and the warhead may be installed directly on the obstacle, which makes it valuable for special applications. The problem was solved using modelling and simulation methods, in particular, CFD-FEM implemented in the Ls-Dyna code. It was assumed as an axisymmetric issue in computational fluid dynamics, where space discretization for each option was built with two-dimensional elements, which ensured efficient calculations. The core numerical model was successfully validated based on the available data in quantitative terms. Analyses showed that at close ranges, under two diameters of the liner, the projectile fails to reach its optimal parameters, impacting the target with relatively low velocity. This effectiveness is also deteriorated by the projectile’s geometry, which at this moment is still not final. Studies on the projectile’s post-perforation energy revealed a dependency on the EFP’s distance from the target, with the most significant effects observed within a range of one liner diameter. Beyond the distance of two diameters, further changes in effectiveness are minimal, with slight variations attributed to computational method inaccuracies.
Determination of load-carrying capacity of back-to-back C-profile beams subjected to pure bending
The present work concerns the strength analysis of back-to-back steel C-profiles subjected to pure (4-point) bending. The load-carrying capacities of considered beams were determined using experimental and numerical tests. Numerical analysis was performed using the finite element method (Ansys code) considering the full nonlinearity of the material and large displacement and strains. Three different numerical models were elaborated to adjust the results to experimental ones. The one of numerical models was based on assumption of doubled wall thickness. The experiments have been conducted for beams with two different thicknesses. In the study, the length of the beam and the distance between the supports were taken into account. Two C-beams designated for the tests were connected using spots welds deployed at adequate places. The results of numerical simulations based on different approaches have been compared with those of experimental ones. In general, the results of the numerical simulations are in a good agreement with the experiment.
Surface settlement prediction of short-distance double-hole tunnel based on stochastic medium theory optimization algorithm
It is of great significance to predict the displacement and deformation of surface settlement during the construction of short-distance double-hole metro tunnels to prevent dynamic disasters caused by surface settlement during construction. The stochastic medium theory is studied in this paper, the optimal algorithm of stochastic medium theory is proposed, which is considered the tunnel section convergence mode, the tunnel space position and the different sections of the tunnel. The accuracy of settlement monitoring data and theoretical prediction values in tunnel construction is analyzed in combination with three engineering cases. The research shows that the applicable condition of the formula is space span ratio (L/B) less than 7; the stochastic medium simplified theoretical prediction curve and the settlement monitoring curve are better fitted, the maximum settlement position and the trend It is basically consistent with the settlement monitoring curve. The theoretical prediction curve settlement groove width is basically consistent with the settlement monitoring curve settlement groove width. The optimal algorithm and the settlement monitoring data have good consistency, which can provide some reference for the project.
Floods – a permanent threat to building structures on the example of the Odra River basin
The article is a summary of the authors’ experiences, who participated in examination and assessment of damage caused by floods to building structures, particularly in the recent period, i.e., in September 2024. The primary goal the authors set was to present the scale of the problem of damage that has been caused by floods, as well as their subsequent consequences. The article also references experiences gained during earlier disasters of similar or even greater magnitude that occurred at the end of the 20th century and in the first decades of the 21st century. Floodwaters pose both structural and microbiological threats to buildings and structures, but they are also a threat to the mental well-being of their occupants and of those providing assistance to the flood victims. The mental state of the specialists assessing the extent of the damage had a significant impact on the quality of those evaluations; therefore, could not be omitted in the assessment of the technical condition of the damaged structures. The impact of floodwaters on the nature of degradation and the durability of building materials is also not yet fully understood. The article, using selected examples from the authors’ own work [1–3] and literature sources [4–6], presents the issue of flood-related damage mainly over the past thirty years. It discusses methods of handling structures that have been in contact with floodwaters and also summarizes the effectiveness of the emergency and repair measures implemented for them. As part of the technical condition assessment, the moisture content of building partitions in residential structures was also examined selectively, along with an evaluation of their salt content. The results obtained were compared with permissible values, as well as with corresponding partitions in buildings of a similar structural state that had not been exposed to floodwaters.
Experimental study and numerical simulation of uniaxial compression on artificial rock samples with Z-shaped fractures
To study the influence of the inclination and length of Z-shaped fissures on the mechanical properties and failure characteristics of the rock mass, this study conducts a series of uniaxial compression tests on rock-like materials with prefabricated Z-shaped fractures. In addition, two-dimensional Particle Flow Code software is used to perform uniaxial compression numerical simulations. The results show that: (1) Other parameters are the same; under different gamma, beta has a significant impact on the variation trend of the compressive strength and elastic modulus of the specimen, showing an "M-shaped" pattern. (2) Under the same conditions, when beta ≠ 0 deg, the compressive strength and elastic modulus of the specimen are negatively correlated with gamma; however, when beta = 0 deg, both are positively correlated with gamma. (3) Under the same conditions, when gamma a ≠ 90 deg, the compressive strength and elastic modulus of the specimen show an "M-shaped" trend with increasing beta. However, when gamma_a = 90 deg, both are negatively correlated with beta. (4) Under the same conditions, for different beta, the compressive strength and elastic modulus of the specimen are positively correlated with gamma_a. (5) The main damage mode of Z-crack specimen is tensile shear damage.
Hazard function, reliability function and mean time to failure of dams
Dams are among the largest structures constructed by human. Their disasters result in numerous casualties and large material losses. The statistical analysis of the reasons for dam disasters was carried out by the International Commission on Large Dams (ICOLD). The analysis included large dams, i.e. dams that are higher than 15 meters or taller than 5 meters and form a reservoir with a capacity of more than 3×106 m3. ICOLD’s study took into account dams built up to 1986 regardless of the type of construction and the material used. The hazard function h(t) and next, the reliability function R(t) were calculated based on that data, using the fitting of the power function in the initial mortality period and a constant function in the useful operation period. The knowledge of the reliability function allowed for calculating the mean time to failure which was 112957 +/-12443 years. It was also demonstrated that in the operation period the annual dam failure ratio is 8.719×10−6 +/- 0.297×10−6. It is a value that is proximate to the recommendations of the U.S. Army Corps of Engineers which suggests the tolerance for the annual dam disaster risk not to exceed 10−6 failures per year for newly-constructed dams and 10−4 failures per year for already existing ones.
Research on the full life cycle safety of levee based on BIM+mechanism algorithm
Levee is the oldest and most widely used water conservancy project in human society, and its safety is directly related to the safety of people's lives and property. According to current regulations, calculations about seepage stability and sliding stability are required during the design and operation management of levees,which including section modeling, soil index organization and boundary condition setting. Due to the characteristic of long distance and multiple sections, these calculations are time-consuming, labor-intensive, and prone to manual errors. This article proposes an innovative research method for the full life cycle safety of levees based on BIM+Mechanisma algorithm. Take West danger Levee project for example, firstly study the three-dimensional geological modeling of levees based on databases, providing the physical and mechanical properties data of geological strata for subsequent calculations; then improve the efficiency of structural modeling and modification by BIM parametric design; finally, construct BIM+GIS data base to integrate the structural and geological information. Then, this article develops finite element seepage calculation program and limit equilibrium method calculation program, further more providing data and functional interfaces to support online calling of external programs. The above research is used for levee design, extracting calculation models from design sections and calling calculation modules for batch solving, hereby improving the situation where levee design and calculations are separated from each other and enhancing design optimization efficiency. On the other hand, applied to digital twin, the safety data base and Mechanism Algorithms of levee are used for safety evaluation after construction.
Integrating rural landscape design and sustainable development: a comprehensive framework for ecological preservation and resource management
Rural landscape design and sustainable development are deeply interconnected, requiring a multifaceted approach that involves scientific design principles, effective resource management, and the active participation of diverse stakeholders. This paper provides a comprehensive examination of the relationship between rural landscape design and sustainable development, focusing on the integration of ecological preservation with sustainable resource utilization. Through a detailed analysis of theoretical foundations, current challenges, and strategic design interventions, this research highlights the socio-economic benefits that arise from well planned rural landscapes, including improved aesthetics, enhanced biodiversity, and increased resource efficiency. The findings emphasize the necessity of balancing environmental conservation with human activity to foster long-term rural resilience and sustainability. This study offers a valuable framework for policymakers, designers, and researchers, supporting future efforts to implement sustainable practices in rural landscape design. By advancing practical strategies and theoretical insights, this research contributes to the development of sustainable rural environments that harmonize ecological health with socio-economic growth, ensuring a sustainable future for rural communities.
The use of the bioinspired nodes with a variable center of rotation to optimize the moments in a portal frame
This publication shows an algorithm for the design of a fully new ridge node in a steel, portal frame with a variable center of the rotation for the girders connected to it. The mechanics of the node was inspired by the mechanics of a bending movement of the human knee joint, due to a variable center of its rotation. This innovative structure of the ridge node can be optimized by any objective function that is based on the bending moments, occurring in the portal frame, for any chosen type of loads or their combinations. The proposed algorithm is presented using two specific examples of the portal frame for two, completely different objective functions. The results for both examples were compared to the benchmark model with a classic connection in the ridge, using an engineering program using finite elements analysis. The whole work was concluded by showing the results and potential directions for further development of such new technology.
Dual-column reinforced steel modular cabins in electrical infrastructure: component property and structural seismic performance
This study proposes a compact seismic reinforcement strategy for stacked steel modular cabins used in energy infrastructure construction. Modular construction offers significant benefits, including increased construction efficiency, reduced environmental impact, and improved safety. However, the seismic performance of modular structures presents unique challenges, particularly in earthquake-prone regions. To address these challenges, the paper presents a reinforcement method that incorporates corrugated steel plate walls at key structural locations, particularly at the lower corners of the ground floor. This approach is designed to improve lateral stiffness and energy dissipation without compromising construction simplicity or cost effectiveness. Finite Element Analysis (FEA) was used to evaluate the effectiveness of this method and demonstrated significant improvements in seismic performance. The results indicate that the proposed reinforcement reduces stress concentrations and mitigates interstory drift, thereby improving the overall structural resilience of the modular assemblies under seismic loading. The results provide a promising solution for balancing structural performance, ease of construction, and economic considerations in the context of seismic reinforcement for modular infrastructure.
Safe Lighting Point as a new component of road safety elements
The paper presents the results of research, which included measurements carried out on A dedicated test track of the Road and Bridge Research Institute is related to the improvement of safety of road traffic users, in particular pedestrians, cyclists, scooter users, etc. An in-depth analysis of urban monitoring records of accidents in urbanised areas made it possible to conclude that in the event of a collision between a motor vehicle and a column, the lighting set is fragmented, which has a real impact on the risk to the health and life of vulnerable road users. Research work has therefore been undertaken to develop lighting column designs that fulfil the task of significantly improving safety, particularly for pedestrians and cyclists, in the event of a collision between a motor vehicle and a lighting column. The work was directed at analysing the results of measurements of key parameters of a lighting set structure consisting of a column shaft with movable fittings and a bracket. Based on the research material collected, proprietary design solutions for lighting columns were developed, significantly improving pedestrian safety while meeting the passive safety requirements of vehicle users.
Calculation method of stress and deformation of hinged frame beams based on Winkler model
Abstract: Based on Winkler foundation model, the mechanical model and coordinate system of hinged prefabricated anchor frame beam were established in order to quantitatively study the mechanical deformation characteristics of hinged prefabricated anchor beam. The mechanical model of hinged frame beams is simplified to Winkler elastic foundation beams. First, the general solution of beam bottom displacement is obtained by establishing the differential equation of beam deflection line, and then the general solution for rotation angle, bending moment and shearing force of the beam is obtained according to the relationship among beam bottom displacement, rotation angle, bending moment and shear force. The motion equation for the beam is derived based on the boundary and continuity conditions of the hinged frame beam. Then, the difference of structural characteristics between hinged frame beams and traditional frame beams under different anchoring forces is compared. Finally, the influence of external factors (anchorage force, foundation reaction coefficient) and internal factors (section size, cantilever length, hinged position) on the stress and deformation characteristics of the frame beam is compared, and the influence law of various factors is obtained by comparison, which provides a reference for the standardized design of the hinged frame beam.
Recycling and reusing of waste fresh cement mortar through the dormancy-awakening method
This study develops the dormancy-awakening method for recycling and reusing of waste fresh cement mortar. Sucrose (SU, C12H22O11) is utilized as the dormancy agent to delay cement hydration, which can prolong the storage time of the waste fresh cement mortar. Aluminum sulfate (AS, Al2(SO4)3) and calcium formate (CF, C2H2O4Ca) serve as awakening agents to resume cement hydration. The results show that the addition of 0.1% SU in fresh mortar blocks cement hydration for the first 24 hours. AS and CF accelerate the cement hydration process and shorten the setting time. The combined use of AS and CF can further accelerate cement hydration, leading to the normal setting time of cement. The setting time can be flexibly controlled by using dormancy agent and awakening agents. Moreover, the awakened cement mortar has smaller volume of harmful pores compared to normal mortar. The addition of awakening agents can improve elastic modulus and packing density of the hardened mortar according to nanoindentation analysis. Compared to the normal mortar, the compressive strength of awakened mortar is enhanced by 21.0% and 18.3% at 3 days and 28 days, respectively. This study develops the method for recycling and reusing waste fresh cement mortar by using conventional admixtures.
Safety management method for foundation pit design of a subway station: based on stability analysis and deformation monitoring of the foundation pit
In order to effectively monitor the stability data of foundation pit during the construction process, the study proposes a monitoring model that can monitor the deformation state of foundation pit in subway stations in real time. The study analyzes the force state of the support through the deformation mode and extrusion direction of the soil layer, and calculates the displacement and deformation of the soil layer by combining with the hydrological environment around the soil layer. Data monitoring points are set up to monitor the dynamic data of key stress areas. The study was conducted to predict the deformation state of foundation pit with long short-term memory artificial neural network model, combined with fast Lagrangian analysis of continuum for numerical validation. The study revealed that the accuracy of prediction of test data with the research monitoring model was 0.912. The convergence speed of the research model during training was 37.34–38.27% higher than other methods. Meanwhile, the data occupancy of the research model in the prediction process was low and its redundancy was reduced by 10.74–36.17% compared to other methods. During the data prediction process of foundation pit, the mean accuracy of the research method for the prediction of wall deformation and settlement of foundation pit remained above 95%. Therefore, the research method provides an efficient monitoring model for the safety management of foundation pit design in subway stations.
Comparative influence of active mineral admixtures on the strength properties of fiber-reinforced reactive powder concrete
The use of active mineral admixtures in concrete and reinforced concrete technology is one of the most important ways to save resources. Silica fume is one of this type’s most popular and effective admixtures. However, the use of silica fume is not always economically reasonable due to its high cost. The paper presents the results of comparative studies on the effect of various active mineral admixtures on the properties of reactive powder concrete (RPC) and fiber-reinforced powder concrete (FRPC). Five different admixtures were investigated: ground quartz sand, blast furnace slag, fly ash, metakaolin and silica fume. The highest strength values were achieved for RPC and FRPC containing microsilica and fly ash together with metakaolin. The RPC compositions containing fly ash and metakaolin achieved at 28 days an average compressive strength of approximately 125 MPa and a flexural strength of over 16 MPa. This is only an average of 10–20% less compared to concrete containing silica fume, however the cost of silica fume is about 2–3 times higher compared to fly ash and metakaolin. Thus, it becomes possible to replace high-cost silica fume with the proposed composite mineral admixture consisting of fly ash and metakaolin. Adding steel microfibers to the tested RPC compositions can increase compressive strength by 10–20%, depending on the composition. With a steel fiber consumption of 240 kg/m3, the flexural strength increases by 1.5 to 2.3 times, reaching 35 MPa.
The impact of macroeconomic variables on the selected type of traffic crash: a study based on ARDL technique
Urban Jordan has witnessed substantial traffic growth in recent years. This study examines the long-term and dynamic nexus between crash rates in urban Jordan cities and macroeconomic explanatory variables. Three types of crashes have been studied including, vehicle rollover, vehicle-pedestrian crashes, and vehicle-vehicle crashes against the following explanatory variables; the proportion of the population living in urban areas, GDP growth rate, the total length of road networks, vehicle number growth rate, and spaces of the newly added building. Accordingly, a case study method has been used, covering the timeframe from 2004 to 2022, by employing the autoregressive distributed lag (ARDL) technique. The ARDL estimates showed the presence of long-run cointegration between variables for all types of crashes. Furthermore, the ARDL estimates on the long- and short-run indicate a varying effect of the considered explanatory variables by crash type. The results indicate that the expansion of the urban population and GDP growth rate play a significant role in determining crash rate in urban cities. Moreover, this study urges decision-makers to monitor the impact of expected migration on traffic safety, whether from the countryside or neighbouring countries experiencing crises.
Scheduling of construction projects base on Z-numbers
The article addresses the challenge of scheduling construction projects given the considerable uncertainty associated with project time estimation. Afuzzy approach, which allows for modelling uncertainty, is employed to represent the duration of project tasks. It is shown, however, that the most well-known fuzzy numbers do not encompass all aspects of uncertainty. This study thus introduces a novel application of a specific type of fuzzy numbers, the Z-numbers, which allow for the consideration of several factors that strongly influence the estimation process, including individual human characteristics, experience, and the project and task context. The underlying theory is discussed, and its application to the scheduling of construction projects is proposed. The approach and its benefits are demonstrated through a practical example involving the construction of a single-family house. Advantages include a more credible and accurate estimation of task durations that accounts for uncertainty while mitigating subjective, individual, and context-dependent elements. Further research perspectives are also outlined.
Research on the mechanical model and control standards for ground loss rate of shield tunnels underpassing high speed rail tunnels
The analytical models for calculating the longitudinal deformation of existing high-speed railway tunnels when a shield tunnel passes beneath them mostly consider the underlying soil as a homogeneous foundation and neglect the variability of the strata. Taking into account the inherent spatial variability of the strata parameters, this study constructs a new mechanical model for the shield tunnel passing beneath existing high-speed railway tunnels, considering the influence of spatial variability in foundation stiffness, and derives the corresponding finite element solution. Through engineering case studies, the reliability of the established mechanical model for the shield tunnel passing beneath existing high-speed railway tunnels is verified. A stochastic analysis method is used to analyze the longitudinal deformation and internal forces of existing high-speed railway tunnels caused by the shield tunnel passing construction. The research results indicate: (1) For single-line shield tunnel construction, once the stratum loss rate exceeds 0.36%, the probability of exceeding the standards rapidly increases. When the loss rate reaches 0.96%, the probability of high-speed railway tunnel deformation exceeding the standards is already at 97.5%. For double-line shield tunnel construction, once the stratum loss rate exceeds 0.18%, the probability of high-speed railway tunnel performance exceeding the standards rapidly increases, and the risk of shield tunnel passing construction sharply rises. (2) The stratum loss rate during single-line shield tunnel passing beneath high-speed railway tunnels should be kept within 0.36%, while for double-line shield tunnel passing, the loss rate should be controlled within 0.18%.
Benefits of building information modelling in mitigating claims and disputes of construction projects in Jordan
Claims play an important role in construction projects as they can have a significant financial impact that can affect the overall cost and schedule of the project. The introduction of Building Information Modeling (BIM) is changing the traditional methods of the construction industry and has strengthened the influence of the planning process on the entire life cycle of a construction project. Therefore, this research attempts to identify the function of Building Information Modeling (BIM) in mitigating such claims and disputes. To achieve the aim of this research, 380 assessments done by industry specialists were examined using the mean ranking method, the normalization process, the RII and factor analysis. The results of this study quantify the main causes of claims and disputes associated with the contractor and owner, such as financial problems of the contractor (RII 0.792), delays caused by the contractor (RII 0.784), delays in payment of completed work to the contractor (RII 0.794), oral change orders from the owner (RII 0.790). In addition, the results revealed several potential benefits of BIM that include efficient communications between stakeholders (RII 0.852), better visualization (RII 0.846), 3D-Coordination and clash detection (RII 0.830). This survey contributes to the current form of information by identifying the main sources of disputes and claims in projects. In addition to revealing the benefits of BIM that industry experts can use to improve project performance.
The influence of T-stress on the stress field at the crack tip of concrete
The internal structure of concrete is a three-phase material, namely matrix, aggregate, and the interface between them. Concrete, as a widely used material in engineering, its macroscopic mechanical properties and fracture characteristics are crucial for structural safety. Crack propagation is mainly caused by stress concentration near the crack tip, and T-stress, as a constant term stress near the crack tip, plays a decisive role in the crack propagation path. In this paper, the stress intensity factors of cracks near aggregate are calculated by analytical numerical method. Firstly, the contact interface between aggregate and matrix is defined as the spring layer contact interface, and then the analytical continuation method is used. Finally, an approximate analytical solution for the influence of circular aggregates on the stress intensity factor at the crack tip is obtained by calculation. The result show that the cohesive material and T-stress can influence the fracture toughness and the crack tip stress. This provided the basis for simulation of concrete fracture.
Thermal-mechanical responses of steel portal frame under varying fire scenes with diverse protective measures
This study investigates the thermal-mechanical responses of steel portal frame without fire pro-tection and with different fire protection strategies across three fire scenes. Temperature fields and heating curves were derived for the steel portal frame in three fire scenes using FDS simulations. Abaqus was employed to perform thermal-mechanical coupling simulations on the steel portal frame under eight conditions, both unprotected and protected with two types of fire protection. A comprehensive comparison and analysis of the simulation results yielded the following key conclusions: in all three fire scenes, the absence of fire protection and the implementation of two different fire protection measures lead to distinct failure modes in the steel portal frame, yet the lateral displacement response patterns remain consistent. Although fire protection strategies can delay the onset of displacement responses in the steel portal frame during fires, their effectiveness in reducing these responses is limited. Furthermore, fire-resistant boards alter the heat transfer path within the steel portal frame, increasing the temperature differential across the component sections and subsequently amplifying bending deformation. The findings provide valuable in-sights that enhance fire safety design for steel portal frame under diverse conditions.
Strengths and weaknesses of multi-point machine turnouts
In many European countries, the choice of turnout control system is determined by the traditional approach implemented for years on railway lines or systems offered by railway turnout manufacturers. The paper presents a research approach to selecting the optimal switch operation control system based on the reliability parameters of track equipment for high-speed railway lines. In particular, a general, system approach to railway turnouts is necessary. The turnout is a structure equipped with diagnostic devices for the technical condition of the most important operating parameters, intelligent heating devices for the movable elements of the switch area and the crossing area with a movable nose, and standard communication interfaces to and from the turnout. The selection of a turnout control system is extremely important for improving the parameters of railway line availability and the safety of rail traffic. Statistical modelling of the control system for the switch and crossing with a movable nose was based on empirical data for each of the devices according to their safety integrity level, i.e. a measure of the number of operations before a fault occurs. The article presents the results of field tests conducted during the operation of a railway line as well as the results of stochastic tests based on the declarations of the manufacturers of railway traffic control systems, including switch point machines.
Application of metakaolin and cement in the stabilisation of expansive soil: an experimental study
Expansive soils have the inherent property of swelling when they have adsorbed water and shrink when dried. This property of expansive soil causes damage to structures constructed on it. To minimise the impact of the expansive soil, it is necessary to improve existing soil before commencing infrastructural construction activity. Samples were collected from Debre Tabor City from three test pits and tested for identification and characterisation. The soil was improved with cement content of 3%, 5%, 8%, and 10% by the dry weight of the soil. The results show that the optimum cement content was obtained at 10% and that half of the optimum cement content was replaced by metakaolin with 5%, 8%, 11%, and 14%, respectively, 7%, 20%, 23%, 26%, and 29%. The optimum combined additive decreases the plasticity index from 64.76% to 27.5%, free swell index from 134% to 45%, maximum dry density from 1.33 g/cm3 to 1.36 g/cm3, California bearing ratio value from 1.28% to 5.15% at 5% cement and 17% metakaolin.
Research on the compressive strength properties of expanded perlite concrete under alternating temperatures
In order to study the compressive strength performance of expanded perlite concrete under low-temperature alternating action, different mixing ratios, mesh sizes, and temperatures were selected as research parameters in this paper using 90–120 mesh, in vitro incorporation at 0%, 10%, 20%, 30%, and 40%. The external mixing ratio of 30% was used, with mesh sizes of 30–50, 50–70, 70–90, and 90–120 mesh. The low-temperature alternating temperature was –20◦C and 20◦C, and 16 groups of 48 test blocks were designed and manufactured. Concrete compressive strength tests and SEM interface scanning tests were conducted. The results showed that the compressive strength of expanded perlite concrete with 90–120 mesh external addition was higher than that of ordinary concrete, and showed a trend of first increasing and then decreasing with the increase of external rate. When the external ratio was 30%, the compressive strength value was the highest, the compressive strength value increases with the increase of expanded perlite mesh size. Under low-temperature alternating action, the compressive strength values of expanded perlite concrete decrease. When using 90–120 mesh, the compressive strength loss rate gradually decreases with the increase of external mixing rate. When the external mixing ratio was 30%, the compressive strength loss rate was 9.16%, but still higher than that of ordinary concrete. Combining SEM to scan the concrete interface, the failure mechanism of the internal structure of expanded perlite concrete was explained from a microscopic perspective, confirming the rationality of the experimental data. According to the actual test results, it is proposed that using expanded perlite concrete with a 90–120 mesh addition ratio of 30% can effectively improve its compressive and frost resistance properties.
Optimizing of concreting method in mass concrete structure using numerical analysis (roller compacted concrete gravity dam)
In mass concrete structures, the increase in temperature due to hydration heat must be carefully studied to minimize the risk of thermal cracking. Gravity dams, a type of mass concrete structure, rely on their own weight to resist the pressure of water. An important innovation in civil construction is Roller-Compacted Concrete (RCC), a form of concrete compacted using a roller compactor. In this study, 3D numerical simulations were conducted using Midas Civil software to analyze the development of hydration temperature within the RCC Tannur Gravity Dam structure in Jordan. The 3D geometric modeling was limited to the cross-section (middle section) of a 15-meter-wide monolithic dam block, assuming symmetry on both sides of the section. Adiabatic boundary conditions were applied to the model to prevent heat loss from the cement hydration reaction. A construction stage analysis was conducted to determine the temperature evolution during each stage of concrete placement. Several simulation scenarios were analyzed, varying the layer thickness (3 m and 4 m), the concreting sequence, and the initial placement temperature of the RCC (20◦C, 25◦C, 30, and 35◦C). Concreting Scheme 2 not only lowers the maximum hydration heat temperature and the associated thermal stress but also speeds up the construction of a dam block by increasing the RCC layer thickness. The results of the numerical modeling demonstrated that controlling the heat of hydration in mass concrete structures can be effectively achieved by optimizing construction methods and parameters.
Elastic buckling of a simply supported functionally graded beam with rigid partitions
The subject of this paper is a simply supported functionally graded beam in three variants: (A) without rigid partitions, (B) with two rigid partitions, and (C) with four rigid partitions. The mechanical properties, specifically Young’s modulus, vary symmetrically in the depth direction of these beams. An analytical model of the beam, considering the individual nonlinear shear deformation of a plane cross-section, has been developed. Two differential equations of equilibrium for the beam, based on the principle of stationary total potential energy, were derived. This system of two equations was approximately solved for each beam variant, and the critical forces were determined with the distinguished shear effect coefficient. Detailed calculations were performed for exemplary beams with selected dimensionless sizes and mechanical properties. The results of these calculations are presented in tables and figures. The main goal of the research is to develop an analytical model of this beam and investigate the impact of rigid partitions placed within the beam on the critical force.
Critical temperature evaluation for steel column exposed to fire – Rankine–Merchant approach
An alternative computational approach to the critical temperature specification for a steel column, related to the fire conditions and associated with the loss of the capacity to safely resist the loads applied to the said column is presented and discussed in detail. The algorithm recommended by the authors has been derived from the empirical Rankine–Merchant rule, with parameters calibrated so as to obtain quantitative agreement with critical temperature estimates arrived at after application of the conventional code-based approach. It has been indicated, that this approach results in an iterative calculation. Knowledge of the critical temperature determined for given structural component or a substructure under assumed fire development scenario allows for identification of its fire resistance interpreted as the forecast time of reliable service when subjected to the influence of high temperature. Numerical example presented in this paper pertains to the column devoid of any restrictions in elongation, not fire protected and heated uniformly around the whole perimeter and along the whole length. To simplify the example it has been assumed, that at any given moment of fire steel temperature is constant in the column cross-section and increases with increasing temperature of surrounding fire plume. The approach proposed by the authors allows for verification, in both qualitative and quantitative terms, of the influences exerted by geometrical imperfections of various origins on the final critical temperature specifications, in particular those related to a potential eccentricity of load application point as well as those induced by the longitudinal axis of column deviating from straightness.
Alternative method for determining grain size distribution with use Doppler radar
Blasting mining is a set of activities that can be divided into a sequence of repetitive tasks. Primarily it is drilling, blasting, loading with the hauling and crushing. Drilling and blasting have the greatest impact on the economic indicator of the whole process. Their aim is to achieve the most optimal fragmentation of the blasting wall. It follows that an accurate and efficient fragmentation assessment process is one of the main indicators of blasting efficiency. Nowadays, sieve analysis is the most accurate method. However, this is a time-consuming and labour-intensive method. This is a predictive method, the disadvantage of which is the absence of the actual fragment size, which is also associated with inaccuracy. Currently, when the emphasis is on optimizing processes with environmental impact, finding a more efficient evaluation method that provides more accurate results than classical prediction procedures is even more relevant. The question of evaluating the grain size has been considered by many experts. This paper discusses the use of the reflection of flying fragments and their evaluation by Doppler radar directly during blasting. These measurements specify the size of the fragments and blasting speed up the process of evaluating the grain size of the muck-pile material.
Environmental life cycle assessment (LCA) of model massive timber and concrete buildings. Implementation of cross-laminated timber (CLT) in an educational facility at the Forest Botanical Garden Marszewo in Gdynia
During the second decade of the 21st century, the effects of climate change became particularly noticeable, as population growth and aggressive urbanisation degraded the natural environment. In modern construction industry, the concepts of sustainable development and life cycle assessment (LCA) are important, covering the investment process from design and construction to operation and potential demolition. Wood, a natural raw material present in architecture for centuries, unites the ecological, economic and social principles of sustainable design. Thanks to innovative processing techniques such as cross-laminated timber (CLT) technology, wood can meet the challenges of modernity. Given the growing consumer interest in pro-environmental attitudes and the tightening of regulations within the European Union, the main emphasis will likely be on choosing environmentally friendly materials with a low carbon footprint, favourable energy balance, and ultimately, recovery or reuse potential. Based on this hypothesis, the paper presents a comparative LCA analysis of CLT and concrete technology for the implementation in an educational building at the Forest Botanical Garden Marszewo in Gdynia.
Experimental studies on an extended end plate joint with prestressed bolts
This paper presents the results of an experimental study of an extended end plate moment connection with prestressed bolts. Increments in bolt forces under loading were measured, as two solutions to eliminate those were compared. The first one consists of using a thick extended end plate to reduce prying action, the second one introduces a spacer plate to eliminate prying completely. Limiting increments in bolt forces is essential in the design of joints working under cyclic load, which can be prone to fatigue failure. Loss of preload was measured. Four types of connection setups were studied, two of which included a spacer plate installed between the extended end plate and a column flange. M16 grades 8.8 and 10.9 were used. The beam element was made of IPE 400 section, and the column element was made of HEB 220 section – both of S355-J2 grade steel. The possibility of using bolts not dedicated to prestress was explored. Finite Element Analysis using ANSYS Workbench software was performed. Results were summarised and discussed.