Methodology for Assessing Embodied Carbon in Bridge Structures
This study introduces a methodology for evaluating the embodied carbon of building materials and structural elements. The approach includes relevant formulas and step-by-step procedures to systematically assess carbon emissions associated with material production and construction processes. While actual numerical results are not presented in this work, the methodology provides a framework for applying these calculations in practice. Operational carbon is not considered in this study but is identified as a topic for future research. Overall, the proposed methodology offers a structured approach to analyzing embodied carbon, supporting further studies and adaptations in construction projects aimed at sustainable development.
Bridge sustainability, Embodied carbon, Operational carbon, Life Cycle Assessment, Environmental impact, Infrastructure in Uzbekistan
Research on the thermal conductivity of products made from industrial waste
The article provides information on the condition and types of building materials produced in our country on the basis of industrial waste.
building materials produced on the basis of industrial waste ,thermal insulation, energy saving, foam concrete, aerated concrete, asbestos
Subsidence of the railway track embankment at the boundaries of water pipelines
The article investigates the impact of water pipeline malfunctions on railway embankment parameters, specifically examining the effect of soil moisture on the deformation (settlement) of both the embankment and the water pipeline itself. To solve this problem, the finite element method was employed, and multiple variant calculations were performed using Midas software. The study determined and compared the deformation (settlement) of the embankment and water pipeline for two types of soil moisture, embankment heights of 2, 3, 4, 5, and 6 meters, and a combination of three types of loads.
railway, water pipes, earthwork, moisture, settlement, deformation
Optimization of the design of bridge intermediate supports
This scientific article covers issues of improving the intermediate supports of bridges. The design features of existing monolithic supports were analyzed, and existing shortcomings in terms of their shape, dimensions, and material consumption were identified. Three design options based on monolithic reinforced concrete have been proposed, and their seismic resistance, load-bearing capacity, and economic efficiency have been parametrically compared. It has been proven that the second proposed structural variant is the most optimal solution in terms of material consumption, economic indicators, and seismic resistance. The research results provide scientifically based recommendations for practical application in improving bridge intermediate supports.
intermediate support, monolithic reinforced concrete, seismic stability, structural form, parametric analysis, load capacity, economic efficiency, optimization
and Assessment of Critical Spatial Deformations and Internal Force States of Continuous Monolithic Reinforced Concrete Bridges under Strong Seismic Actions Using MiDAS Civil
The article presents the results of spatial seismic calculations for a continuous monolithic reinforced concrete bridge structure using the spectral method implemented in the MiDAS Civil software package. In the study, a spatial computational model of the structure was developed, taking into account the combined spatial behavior of the bridge span structure, intermediate and end supports, as well as the prestressed reinforcement system. The computational model is based on the finite element method, considering the stiffness properties of the structure and the interaction of bending, torsional, and transverse shear deformations. Through spectral analysis, the internal forces and displacements induced by standard seismic loads on the bridge's structural elements were evaluated. The obtained results allow for the determination of seismic stability in continuous monolithic bridges, refinement of calculation schemes, and optimization of design and technological solutions for seismically active regions.
transportation structures, bridge, earthquake-resistant design, Midas Civil, linear spectral analysis, post-tension
Assessment of the block strength of dispersely-armonized basalt fiber, complex-modified small-grain fiber concrete
The article presents the results of a study on the impact strength of fibroconcrete with basalt fiber obtained on the basis of a complexally modified ash aggregate and "POLIMIX" superplasticizer cement binder. Based on the conducted experimental studies, it was established that during the volumetric hardening of fine-grained concrete with basalt fiber, as well as the complex modification of the cement matrix of basalt fiber concrete with ash filler and "POLIMIX" superplasticizer, an ultra-strong surface layer is formed in the composite, which creates a monolithic mineral enclosure, significantly improving all the physical and mechanical properties of the material.
concrete, strength, stability, corrosion, elasticity modulus, fine-grained concrete, alkali resistance and acid resistance
Economic efficiency of implementing modern prefabricated reinforced retaining walls
In this article, the economic efficiency of implementing modern prefabricated reinforced retaining walls is evaluated by comparing the costs associated with the construction and installation of traditionally used retaining walls, as well as the expenses required to eliminate potential shortcomings and problems during their service life. Justifying the efficiency of prefabricated reinforced retaining walls plays an important role in enhancing the technical and economic performance of reinforced concrete highway bridges and overpasses. Replacing traditionally used retaining walls with prefabricated reinforced retaining walls allows for accelerated construction processes, more effective allocation of materials and labor, and reduction of long-term operational costs of the structures.
Prefabricated panel, bridge approaches, economic efficiency, bridge, overpass, retaining wall, structure, concrete, reinforcement, service life, technical condition
Methods for determining soil pressure on underground structures under seismic influences
This article examines methods for determining soil pressure on underground structures. Five methods for determining ground pressure on underground structures were considered, and the calculation results were compared and presented in the form of graphs. In conclusion, an analysis of the above-mentioned methods for calculating the seismic resistance of underground structures was conducted and their shortcomings were presented.
Pressure, soil, normal and tangential stresses, seismic impact, seismic waves, prevailing period, quasistatic load, normal tangential stresses, extreme stresses, plane, stress concentrations, wave theory, seismodynamic theory
Oscillation of a prestressed span structure of a reinforced concrete railway bridge with mass in horizontal motion
This work examines the features of calculating the strength of reinforced concrete railway bridges with a moving load and a movable oscillator. The methods of finite elements and finite differences were used. When solving the problem of oscillations of a beam with distributed parameters under the action of a moving concentrated force and mass, "parasitic oscillations" are eliminated by choosing a step in time depending on the speed of the load's movement. As an example for moving cargo or mass, the mass of the Talgo locomotive was taken. Such a mass velocity has been determined that it is possible to use the model of the force moving with a lower velocity, otherwise the model of the oscillator must be adopted. With an increase in the horizontal velocity of the oscillator, the deflection of the beam increases, and the vertical oscillations of the mass also increase.
reinforced concrete, beam, reinforcement, concentrated force, concentrated mass
Justification of the purposes of using basalt fiber in cement concrete
The creation of modern high-efficiency building materials and products, to which the demands are constantly increasing, can be successfully implemented using technologies using composite materials. Particularly promising are dispersed reinforced concrete, in which a strong matrix and reinforcing fibers are successfully combined. The matrix provides high compressive strength, bending strength, and durability, while dispersed fibers are characterized by significant tensile strength, high elastic modulus, and the ability to distribute loads throughout the entire volume. Such a combination increases crack resistance, improves the operational properties and durability of structures, and opens up new possibilities for use in modern engineering structures and industrial construction.
concrete, basalt fiber, strength, stability, corrosion, elasticity modulus, fine-grained concrete, alkali resistance and acid resistance
Methodology for assessing the dynamic impact of rolling stock on the subgrade and justification for its reinforcement in the area of rail joints
The article proposes a method for assessing the dynamic impact of rolling stock on the subgrade in the rail joint area, taking into account speed regimes and axial loads, based on the calculated relationship Kпг→Y→σ(z) and a normative check using the criterion σ(z)≤0.5 MPa. An assessment of the conditions for exceeding the standard stresses during high-speed passenger and freight traffic has been carried out, and the introduction of the dynamic coefficient kdyn to account for shock-pulse effects has been justified. It has been shown that the use of a combined reinforcement system of ‘geotextile + flat geogrid’ reduces vertical stresses in the main subgrade area by 25–30% and forms a standard reserve of bearing capacity of the foundation. The results obtained can be used in the design and modernisation of railway lines with mixed and high-speed traffic in rail joint areas.
Dynamic impact, rail joints, subgrade, dynamic addition coefficient, dynamic coefficient, vertical stresses, geosynthetic materials, geotextiles, geogrids, track bed reinforcement, high-speed traffic, axial load, standard stresses
Monitoring the technical condition of operating transport tonnels
This scientific work is devoted to the issues of monitoring the technical condition of operating transport tunnels. The study analyzes modern methods for determining and assessing deformations, cracks, settlements, and other malfunctions arising during the operation of tunnel structures. The importance of monitoring systems in ensuring the safe and reliable operation of transport tunnels is substantiated. The work examines the advantages and disadvantages of geodetic, geotechnical, and automated monitoring methods based on domestic and foreign scientific sources. Natural and man-made factors affecting tunnel structures, including rock deformation, the influence of groundwater, seismic activity, and increased loads, were also analyzed. Based on the monitoring results, the possibilities of assessing the technical condition and preventing emergencies are highlighted.
Transport tunnel, operation, technical condition, monitoring, geotechnical, storage, current inspection, periodic inspection, special inspection, inspection and testing of artificial structures, conductivity, load-bearing capacity, durability assessment
The problem of load combination in earthquake resistance theory
This scientific work addresses the problem of combining seismic loads with other types of actions within the framework of the general theory of earthquake-resistant design and modern methods for designing buildings and structures. Particular attention is paid to the transition toward multi-level performance-based design, which requires structural analyses for earthquakes of varying intensity and recurrence. A comparative analysis of load combination factors adopted in the regulatory documents of Russia, European countries, the United States, New Zealand, and Albania is performed. It is shown that the existing load combination factors are largely empirical, do not adequately account for the statistical characteristics of loads and the seismological features of the construction site, and are not mutually consistent.
seismic resistance theory, load combinations, seismic impacts, earthquakes, accelerogram recordings, limit state coefficient,special inspection, inspection and testing of artificial structures, conductivity, load-bearing capacity, durability assessment
Use of basalt reinforcement, mesh, and fabrics as structural materials in geotechnical and earthworks
This article analyzes the possibilities of using basalt fiber–based composite reinforcement in geotechnical, hydraulic engineering structures, as well as in buildings and civil engineering constructions. The physical and mechanical properties of the material are compared with those of steel reinforcement, and the most appropriate fields of application are identified.
basalt reinforcement (basalt rebar), composite materials, soil reinforcement, geotechnical engineering, foundations, corrosion resistance, low-rise construction
Seismic Performance of Continuous Monolithic Bridges
The article highlights the issues of enhancing seismic resistance of transportation structures located in seismically active regions of Uzbekistan. Based on real earthquake records, the methodology for selecting bridge constructive parameters and performing structural analysis is examined. The study applies the Timoshenko beam model, spectral analysis, and time-history methods, with a case study of a reinforced concrete overpass in Jizzakh. Results indicate that post-tensioned tendons significantly improve seismic performance.
transportation structures, bridge, earthquake-resistant design, real earthquake records, Timoshenko beam model
Concrete for additive construction production in dry hot climate conditions for transport infrastructure
The article examines the challenges and solutions for 3D concrete printing in arid, hot climates for transport infrastructure construction. It analyzes the detrimental effects of high temperatures, low humidity, and cyclic loading on the printing process and structural durability. Modern approaches to designing specialized concrete composites are presented, including mix designs with complex admixtures and reinforcement methods. The advantages of additive technologies for creating climate-adapted, functionally integrated, and cost-effective structures are highlighted.
Additive Construction, 3D Concrete Printing, Arid Hot Climate, Transport Infrastructure, Printable Concrete
Application of new seismically insulated supporting parts for seismic protection of bridge intermediate buildings
This paper presents the outcomes of experimental investigations into the application of newly developed seismic protection support components for enhancing the seismic safety of bridges and overpasses.Based on the results of experimental tests, the amplitude-frequency characteristics of traditional and new seismic protection components were compared, and the effectiveness of the new seismic protection component was substantiated. In addition, based on graphs, the diagrams of the installation of support parts for seismic protection of bridges, the AFCh of vibrations of a special unprotected support, the displacements of the span structure and the upper part of the support during seismic isolation of one span structure, the amplitude-frequency characteristics of the displacement of the span structure and the upper part of the support when the first span structure is combined with seismic protective and the second with movable and stationary support parts are compared.
Amplitude-frequency characteristics, span structure, movable and fixed supporting parts, heavy span structure, upper part of the support, strong earthquakes, design moment on the foundation, oscillation periods, fastening of span structures
Physicochemical analysis of expanded clay concrete modified with mineral and chemical additives
This article examines the physicochemical properties of expanded clay concrete compositions modified with mineral and chemical additives. In the research process, the influence of additives on the microstructure of cement stone, hydration processes, and the formation of the filler-bonding interface zone (CZ) was analyzed. The results of physicochemical analysis showed that mineral and chemical additives compress the cement matrix, reduce capillary porosity, and increase the structural stability of the interface zone. The obtained results have scientific and practical significance for the creation of energy-saving and high-performance expanded clay concrete materials.
Expanded clay concrete, mineral additives, chemical additives, physicochemical analysis, cement stone, microstructure, filler-binder interface zone (CZ), hydration processes, capillary porosity
Modern building materials based on household waste and natural raw materials
The article discusses the recycling of household waste, plastic, polymers and organic waste to create various types of building materials, as well as the production of paving slabs by heating plastic and natural sand at high temperatures.
Energy-efficient building materials, household waste, energy saving (bakalashka), paving slabs, car tires
Mutual influence of parallel tunnels in an elastic medium in the epicentral zone of an earthquake
When analyzing the interaction of parallel metro running tunnels in dynamic problems involving wave loading, it is necessary to limit the computational domain using artificial boundaries. This requires the formulation of boundary conditions that ensure transparency for both incoming external waves and internal waves reflected from structural elements. In this paper, exact non-reflecting boundary conditions are proposed. Based on the developed mathematical model, the behavior of tunnel linings under the action of longitudinal and shear waves in the epicentral zone of an earthquake is investigated. The numerical implementation is carried out using the finite element method and the Bathe time integration method. The influence of the distance between circular reinforced concrete linings under longitudinal and shear wave loading is studied. The calculation results demonstrate the high efficiency of the proposed transparent boundary conditions, which makes it possible to reliably investigate wave–structure interaction processes in underground structures under plane strain conditions.
elastic medium, lining. transparent boundaries, wave propagation, finite element method, Bathe integration method
On the issue of assessing a monolithic reinforced concrete overpass under seismic impacts
In order to improve the transport infrastructure of the Republic of Uzbekistan, monolithic structures of bridges and overpasses began to be used. The article presents the calculation of a monolithic bridge on the 1083rd km of the M-39 highway passing through the city of Samarkand. The main goal was to determine the structural parameters of the overpass with seismic load, especially the influence of friction forces on the overpass foundation. The calculations were carried out using the Midas Civil software package using the finite element method (FEM) based on linear spectral theory. In the calculations of the Midas Civil PC, carried out within the framework of linear spectral theory, it was determined that the pile pressure on the lower soil does not exceed the limit and the maximum value of the bending moment coincides with the pile head moment.
Bridges and overpasses, stress-strain state, thermal expansion, internal pressure, linear elasticity, finite displacement method, boundary conditions, radial stress, numerical modeling, mechanical behavior, long-term operation
Experience in Implementation and Prospects for the Development of Structural Health Monitoring Systems at Transport and Civil Infrastructure Facilities
The paper presents a theoretical analysis of the integrated operation of structural health monitoring (SHM) subsystems applied to transport and civil infrastructure facilities. Bridge structures are identified as the primary field of SHM implementation due to their complex operational conditions. The study considers instrumental monitoring (stress–strain condition, accelerations, inclinations) and geodetic monitoring (GNSS-based displacement control). Advantages, limitations, and practical applications of each subsystem are discussed. It is demonstrated that the integrated use of monitoring subsystems significantly improves measurement accuracy and enhances reliability of structural condition assessment and forecasting.
structural health monitoring, bridges, GNSS, stress–strain condition, accelerations, inclinometers, displacement monitoring
Vibrations of a rigid beam elastically connected to deformable supports under seismic loads
In practice, there are problems related to the calculation of groups of piles buried in the ground environment with different depths of immersion. At the same time, the main attention is paid to assessing the influence of the external ground environment on the magnitude of pile movement and the development of contact forces at the points of connection of piles with load-bearing beams is evaluated. As the results of monitoring the condition of bridge structures under the action of external forces, especially seismic ones, show, the greatest structural damage occurs at the junction of piles with beams. The oscillatory process of a rigid beam in contact with two piles through elastic elements is studied. The influence of stiffness coefficients on the frequency response of beam vibrations is estimated.
bridge, beam, support, vibration, displacement, ground, seismic load
Parameters of underground metro structure interaction with soil under seismic loads and methods for their determination
The seismic strength or resistance of underground structures mainly depends on the forces of their interaction with the surrounding soil. These interaction forces are governed by specific laws. The simplest law includes an interaction coefficient, which is the primary parameter. The values of this coefficient are determined experimentally. For underground metro structures, experimentally determining the interaction coefficient under dynamic (seismic) loads is a highly challenging problem. This paper suggests a straightforward method to estimate interaction parameters, including the interaction coefficient, based on the strength characteristics of the soil surrounding underground metro structures.
subway, tunnels, soil, seismic impact, interaction, seismic resistance, friction, stress, contact surface
Method for determining the optimal length of the transition part of a railway track plan
On a curved section of a railway track, to smooth out the turn, a curve is considered whose curvature can be equal to the curvature of a circle, and a smooth transition is formed in an optimal way.
The transition part of the railway track, Optimal choice, has a curvature, circle, clothoid, function
Instantaneous axis of helical motion of a rigid body
This study investigates the state of the instantaneous screw axis (ISA) during the motion of a rigid body. It also introduces a method for altering the representation of rigid body motion. The paper demonstrates how translational and rotational motion parameters of a rigid body can be expressed as functions of the invariants of instantaneous screw motion (ISM). By using these invariants, a more generalized and compact formulation of rigid body motion is achieved. The approach helps to describe complex motion behaviors with greater clarity and mathematical efficiency. This framework is applicable to a wide range of mechanical and robotic systems, offering improved insight into motion analysis and control through ISM-based modeling techniques.
Instantaneous screw axis, invariant description of motion, inverse problem
We provide an innovative approach to time series analysis that helps automate autoregressive integrated sliding mean-value authorization model (ARIMA) modeling and greatly facilitates the reliable prediction-building process. Our approach is based on optimization modeling and the separation of the time series into defined seasonal effects, autoregressive (AR) terms, moving average (MA) terms, white noise, and any free variation outside the scope of the chosen model. Simultaneous selection of the corresponding delayed terms and evaluation of their coefficients is achieved by minimizing normalized errors subject to constraints including the limit of the number of combined AR and MA terms to achieve the desired savings through mathematical programming. The White Noise estimator device serves as a stationary benchmark signal for determining Ma coefficients and is modeled using wavelet functions that facilitate the formation of integer linear constraints. We report the results of numerical testing of this methodology in several real data sets and discuss the main consequences for research and practice. Our models (i) have found that one step above other widely used interpretable methodologies, including random forests and gradient enhancement models, achieves forward forecasting accuracy, offers interpretable results, and is computationally consistent.
Optimization modeling, analysis of time series, prediction of waves, white noise., Error counting
Propagation of spherical shock waves in a contiguous elastic-plastic environment
This article studies the propagation of one-dimensional spherical shock waves in a homogeneous medium, represented by soil or ground, modeled as a continuous elastic-plastic medium. The research assumes that the loading shock waves in the elastic-plastic medium filling the surrounding space propagate at a constant velocity. Furthermore, the effective use of directional blasting technology in construction, mining-geological industries, and other technical fields requires determining the relevant mechanical parameters of continuous elastic-plastic media subjected to shock loads. Within the theory of small elastic-plastic deformations, the relationship between the components of the stress and strain tensors in a spherical coordinate system is taken into account.
elasto-plastic medium, underground capacity, soil, explosion, shock wave, elastic potential, tensor, intensity, deformation, stresses
Analysis of the dynamics of the viral infection spread model
This paper analyzes the dynamics of a mathematical model based on a proposed three-dimensional quadratic stochastic operator developed to simulate the spread of viral infections. The model employs Lotka–Volterratype operators defined on a simplex, and the behavior of the resulting dynamical systems under various signatures is thoroughly investigated. The model variables represent the proportions of population groups— susceptible, infected, recovered, and hidden carriers—while the coefficients denote the interaction parameters among these groups. Within the study, the Jacobian matrix is constructed to identify stationary points and classify their stability properties as attractors, repellers, or neutral points. Additionally, the basic reproduction number is calculated analytically to determine the conditions under which the infection may spread. Using this model, the stages of infectious disease progression, the role of hidden carriers in transmission, and the probability of reinfection are analyzed from a mathematical perspective. The results provide valuable insights into real-world epidemiological dynamics and can support the development of effective disease control strategies
Simplex, the Lotka-Volterra operator, signature, attractor, repeller, saddle, Jacobian, population, epidemiology, dynamic system, infection and spread of disease, carriers
Analysis of annual changes in freight turnover of road transport using time series model
This article presents a statistical analysis of the volume of freight turnover in automobile transport for the period 2010–2023. The analysis was performed using Minitab 17 software, with linear and quadratic trend models constructed and their accuracies compared. Additionally, the autocorrelation of model residuals was examined, and a forecast of freight turnover volume for 2024–2026 was made. The results indicate an increasing annual growth trend in freight volume. These results are of great importance for the development of transport infrastructure, the improvement of logistics systems, and the identification of investment directions. During the analysis, the time dynamics of the variables were thoroughly studied, and statistically grounded conclusions were drawn. The findings enabled the formulation of practical recommendations that can be applied in economic forecasting.
Trend, linear trend model, autocorrelation function, error, mean squared error