Vibroengineering Procedia: Table of Contents

Moisture-retaining film-forming compounds for cement concrete pavements in arid climates

Imamaliev, Dilshod — 2026-07-16T00:00:00Z

Vibroengineering Procedia, Vol. 63, 2026, p. 109-114.
Dilshod Imamaliev, Matchon Tukhtayev, Reyhan Akbarli, Mavjuda Ulugbabayeva
In hot and arid climates, rapid moisture loss from freshly placed cement concrete pavements disrupts hydration, leading to reduced strength and durability. This study evaluates novel film-forming compositions based on secondary industrial resources (GACH-3 and spent mineral oils). The research establishes the physicochemical mechanisms of pore colmatation achieved through the synergistic interaction of paraffin-based components and technical oleic acid. Experimental results demonstrate that the optimized composition increases compressive strength by up to 35.1 % and reduces moisture evaporation twofold. Long-term observations (12 months) confirmed significantly reduced porosity and microcrack sizes.

Dynamic parameters and seismic response of reinforced concrete shell roofs of unique buildings during long-term operation

Razzakov, Saidmakhsud — 2026-07-16T00:00:00Z

Vibroengineering Procedia, Vol. 63, 2026, p. 24-34.
Saidmakhsud Razzakov, Mukhlis Akhmed Ogli Hajiyev, Ulugbek Akhmadiyorov
This paper investigates changes in the dynamic parameters and seismic response of reinforced concrete shell roofs of unique large-span buildings during long-term operation. The aim of the study is to evaluate how long-term loading, stiffness degradation, support rigidity, and boundary conditions affect the vibration characteristics and structural safety of shell systems subjected to high-intensity seismic actions. The research combines experimental modeling and theoretical analysis. Shell models and full-scale spatial structures were tested under long-term static loading and forced dynamic actions corresponding to design seismic intensities of 7, 8, and 9 points. The study considers free-standing and coupled conical domes, as well as shells of various geometric forms, with attention to oscillation modes, vibration periods, amplitudes, deflections, residual deformations, and crack development. The results show that long-term operation significantly reduces the dynamic rigidity of reinforced concrete shell systems and increases their deflections and residual deformations. A 5.86-fold increase in column rigidity increased the frequency of horizontal oscillations by 74.3 %, while the influence on vertical vibration frequencies remained limited. Long-term loading increased ultimate deflections by 1.5-2 times, fiber deformations by 2.4-2.75 times, and crack development by up to 2 times. A resolving system of equations for shell deformation under nonlinear creep conditions is proposed for assessing the stress-strain state of structures at the operational stage. The obtained results can be used to improve the seismic safety assessment and rational design of reinforced concrete shell roofs in seismic regions.

Numerical analysis of vortex-induced flow structures and their spectral characteristics behind a square cylinder using adaptive and locally refined grids

Madaliev, Murodil — 2026-07-16T00:00:00Z

Vibroengineering Procedia, Vol. 63, 2026, p. 179-185.
Murodil Madaliev, Eldor Mamurov, Rasul Tadjibayev, Abdulvasiy Gaynazarov, Abdurashid Mamirov, Gazaloy Nishonova
In this paper, the vortex flow structures formed behind a square cylinder and their spectral properties are numerically investigated based on the 2D URANS k-ω SST model (Re ≈ 4.7×104). The study compared locally densified and adaptive anisotropic (Hessian-based) meshes. The calculations were performed using the PISO algorithm and second-order accuracy (CFL ≤ 1, Δt≈T/200). The results were compared with experimental data on Strouhal number, drag and lift coefficients, and velocity profiles. The adaptive mesh more accurately represents the wake zone and sharp gradients of the flow, allows for reliable estimation of spectral parameters (frequency and amplitude), and reduces numerical diffusion. Some limitations of the 2D URANS model are also indicated.

A robotic spine exoskeleton based on linear electric actuators for spinal deformity correction

Tassybayeva, Ulpan — 2026-07-16T00:00:00Z

Vibroengineering Procedia, Vol. 63, 2026, p. 76-81.
Ulpan Tassybayeva, Sandugash Orazaliyeva, Javlonbek Rakhmatillaev, Nursultan Zhetenbayev, Gani Sergazin
This paper presents a conceptual design of a robotic exoskeleton for active correction of spinal deformities. Unlike existing support-based systems, the proposed approach is correction-oriented and uses a multi-segment structure with linear electric actuators. A comparative analysis of actuation systems was conducted, and the FOCOTECK LA14C actuator was selected for wearable application. The exoskeleton is designed as a vest-based system with actuators mounted via articulated joints to improve kinematic compatibility. A CAD model was developed to evaluate the feasibility of the design. Future work will include simulation and experimental validation using a 3D-printed prototype

Design and development of a modular cable-driven lower-limb exoskeleton for early rehabilitation after hip and knee endoprosthesis

Otkilov, Munaitpas — 2026-07-16T00:00:00Z

Vibroengineering Procedia, Vol. 63, 2026, p. 82-88.
Munaitpas Otkilov, Zhanibek Issabekov, Dauren Bizhanov, Rakhmatillaev Javlonbek, Yussupova Saltanat, Nursultan Zhetenbayev
This paper presents a modular lower-limb exoskeleton concept fo4r early rehabilitation after hip and knee endoprosthesis. The system combines a cable-driven (Bowden) mechanism, a Hip-Knee modular architecture, and an adaptive Assist-as-Needed control strategy. The “one motor – two functions” principle reduces system weight and improves energy efficiency. Real-time control based on IMU and force sensors ensures accurate and safe motion. The proposed solution provides a lightweight and adaptive approach for simultaneous rehabilitation of the hip and knee joints.

Static strength assessment of industrial traction unit bogie frames using finite element method

Abdurasulov, Sherzamin — 2026-07-16T00:00:00Z

Vibroengineering Procedia, Vol. 63, 2026, p. 186-191.
Sherzamin Abdurasulov, Nuriddin Zayniddinov, Abdulaziz Yusufov, Shukhrat Jamilov, Shohijakhon Kudratov
This paper addresses the static strength assessment of bogie frames for PE2 (M, U) series industrial traction units used in the mining industry. Currently, a significant portion of the widely operated PE2M and PE2U traction units has been in service for 40-50 years. Given that the manufacturer-specified service life for these units is 24 years, there is a critical need to justify the feasibility of extending their operation to more than double their original design life. The objective of this research is to determine the mean stress of the bogie frame loading cycle. A 3D model of the bogie frame was developed using SolidWorks, and structural analysis was performed via the Finite Element Method (FEM) in Ansys Mechanical. The finite element analysis results indicated a mean Von Mises stress of 63 MPa, and a safety factor of 2.65. Based on the findings, relatively higher stresses were observed in the zones beneath the central pivot plate of the pivot transom. The low values of mean stress, combined with the biaxiality levels, confirm that the bogie frame possesses sufficient static strength. These research findings can be utilized to evaluate the fatigue strength and residual life of the bogie frame, as well as to justify its service life extension.

Nonlinear bending and experimental validation of circular reinforced concrete and steel-reinforced concrete thin plates with compliant support contour

Razzokov, Khurshidkhon — 2026-07-16T00:00:00Z

Vibroengineering Procedia, Vol. 63, 2026, p. 192-200.
Khurshidkhon Razzokov, Jamshidkhon Razzokov, Ikramboy Sattarov
This study investigates the nonlinear bending behavior of circular thin reinforced concrete (RC) and steel-reinforced concrete (SRC) plates under short-term and long-term loading, with particular attention to the influence of support contour compliance. A calculation framework is developed for the stress-strain analysis of axisymmetrically loaded circular plates by accounting for geometric nonlinearity, material nonlinearity, reinforcement effects, and time-dependent deformation. Experimental studies were carried out on circular RC plate models interacting with a support ring, and the measured deflections were compared with theoretical predictions. The results show that the proposed model captures the main features of plate deformation, including the nonlinear increase in deflection with load and the redistribution of the stress-strain state near the contour. For the considered loading cases, the discrepancy between calculated and experimental deflections did not exceed 17 %, which confirms the engineering applicability of the developed approach. It is also shown that support contour compliance significantly affects the long-term behavior and load-bearing response of the plates. The obtained results can be used to improve the design and assessment of circular RC and SRC plates, especially in structures where nonlinear effects and contour deformability must be taken into account.

Minimum-cost flow optimization of road freight delivery in a mountainous transport network: a case study of Kyrgyzstan

Kurmanov, Ulan Esenbekovich — 2026-07-16T00:00:00Z

Vibroengineering Procedia, Vol. 63, 2026, p. 201-210.
Ulan Esenbekovich Kurmanov, Kunduz Adashbekovna Zhunushalieva, Asel Zhailoobekovna Saparbekova
This paper presents a minimum-cost flow model for optimizing road freight delivery in a mountainous transport network, using Kyrgyzstan as a representative case of a landlocked Central Asian economy. The proposed approach integrates transportation cost, handling cost, and time-delay penalties into a unified linear programming framework in order to evaluate both domestic and cross-border freight movements under capacity and delivery-time constraints. The freight system is represented as a directed transport graph whose nodes correspond to logistics hubs and demand points, while arcs describe road corridors with different operational characteristics. The model was implemented in Python using a linear programming solver and calibrated with recent transport statistics and corridor data. For the domestic scenario with a balanced freight demand of 500 tons, the optimized total logistics cost reached 18,750 USD, of which 68 % corresponded to transportation, 17 % to handling, and 15 % to delay-related costs. For the extended cross-border scenario with a total volume of 800 tons, the optimized cost increased to 32,400 USD, while delivery time rose to 36-42 hours due to border-related delays. The results demonstrate that, in mountainous freight systems, time-dependent factors substantially affect route efficiency and total logistics cost. The study shows that minimum-cost flow optimization can support engineering decision-making in freight transport planning, corridor modernization, and customs process improvement in Central Asia.

Performance analysis of a bottom-discharge inertial rotor for high-speed excavation in hard soils

Kozbagarov, Rustem — 2026-07-16T00:00:00Z

Vibroengineering Procedia, Vol. 63, 2026, p. 211-217.
Rustem Kozbagarov, Bakytzhan Kyrgyzbay, Kenes Zhussupov, Gaukhar Shegenova, Nurbol Kamzanov, Rashida Duisen, Zhuldyz Dainova
The intensification of earthwork operations is closely linked to the expanding use of continuous-action excavation systems, where rotary excavators play a key role. This study addresses the need for higher productivity in hard and frozen soils by introducing an innovative high-speed working body: a bottom-discharge inertial rotor using a “top-down” digging method. Experimental results for a 1540 mm diameter rotor at cutting speeds of 2-9 m/s in Category III-IV soils demonstrate that at a speed of 4.4 m/s, productivity reaches 256 m3/h. This is 4.5 times higher than that of traditional gravity-based rotors, while energy consumption is reduced by 15-40 %. By optimizing the rotor’s design, this technology ensures increased operational efficiency, improved soil transport, and a significant reduction in the machine’s overall weight. These findings provide a scalable engineering framework for developing next-generation, energy-efficient excavation machinery.

AlmatyExoElbow: development and biomechanical analysis of a 2-DOF cable-driven elbow exoskeleton

Bizhanov, Dauren — 2026-07-16T00:00:00Z

Vibroengineering Procedia, Vol. 63, 2026, p. 89-95.
Dauren Bizhanov, Nursultan Zhetenbayev, Nussibaliyeva Arailym, Raushan Kalykpaeva
This paper presents the design and preliminary structural assessment of a cable-driven elbow exoskeleton, AlmatyExoElbow, intended for upper-limb rehabilitation. The proposed system employs a modular architecture to improve biomechanical compatibility while reducing distal segment mass. The exoskeleton provides two degrees of freedom, including flexion-extension and forearm pronation-supination. A cable-driven mechanism enables remote actuator placement and reduces parasitic loading associated with mechanical-anatomical axis misalignment. A 3D CAD model was developed and evaluated using finite element analysis in SolidWorks Simulation. Stress, displacement, and strain distributions were analyzed to identify critical structural regions and guide future design optimization. The results provide an initial assessment of the proposed concept and support further development of rehabilitation-oriented elbow exoskeleton systems.

Influence of stiffness parameters on the beat period of a coupled two degree of freedom oscillatory system

Zhauyt, Algazy — 2026-07-16T00:00:00Z

Vibroengineering Procedia, Vol. 63, 2026, p. 1-6.
Algazy Zhauyt, Marzhan Bauyrzhan, Ulagat Tursynkali
This paper presents a parametric investigation of the beat phenomenon in a two DOF mechanical oscillatory system coupled through elastic elements. The system consists of three masses connected by springs with stiffness coefficients c1, c2, and c3. Using Lagrange’s equations of the second kind, the mass and stiffness matrices were formulated, and the natural frequencies ω1 and ω2 were determined analytically. The beat period, defined as Tb=2π/ω2-ω1, was studied as a function of stiffness parameters c1 and c2. Numerical simulations in Python were conducted over a wide range of stiffness ratios, and contour maps were generated to illustrate how variations in stiffness coupling influence the dynamic interaction between modes. The results demonstrate that when c1 and c2 are close in magnitude, the modal frequencies converge, leading to a long beat period and pronounced energy exchange between oscillators. Conversely, greater stiffness asymmetry increases modal separation and shortens the beat cycle. The study provides valuable insights into tuning coupled oscillatory systems for vibration control and energy transfer optimization.

Non-stationary transverse vibrations of a three-layer viscoelastic plate: approximate model and frequency analysis

Yаkhshiboеv, Sherzod — 2026-07-16T00:00:00Z

Vibroengineering Procedia, Vol. 63, 2026, p. 7-17.
Sherzod Yаkhshiboеv, Numonkhon Rаzzаkov, Khilola Khаydаrovа
This paper presents an approximate mathematical model for the analysis of non-stationary transverse vibrations of a three-layer viscoelastic plate composed of two load-bearing face layers and a deformable core. The governing equations are derived within the framework of the three-dimensional linear elasticity theory under plane deformation assumptions and reduced to a form suitable for engineering calculations. A frequency equation for harmonic vibrations is obtained and solved numerically using Maple 17. The analysis is performed for plates with steel and aluminum face layers combined with different core materials, including polymer, fiberglass, wood plastic, and textolite, for several core thicknesses. The numerical results are presented as frequency-wave number relationships and used to evaluate the influence of geometric and physical-mechanical parameters on the dynamic response of the plate. It is shown that the lowest vibration frequency increases with increasing wave number and core thickness. For identical geometric parameters, plates with aluminum face layers exhibit slightly higher frequencies than plates with steel face layers, whereas the core material significantly affects the frequency level due to the combined influence of stiffness and density. The proposed model can be used for rapid frequency assessment of layered structural elements subjected to transverse dynamic loading. Viscoelastic dissipation in the layers is introduced through the elastic-viscoelastic correspondence principle, and the formal range of applicability of the model is identified in terms of the dimensionless wave number kh0 and the face-to-core thickness ratio. The proposed model is verified against a Semi-Analytical Finite Element (SAFE) plane-strain 3-D elasticity benchmark, against which it agrees substantially better than the classical Kirchhoff-Love thin-plate theory within the entire claimed applicability range.

Experimental and analytical assessment of the erection state of large-span reinforced concrete shell structures

Ibragimov, Bakhrom — 2026-07-16T00:00:00Z

Vibroengineering Procedia, Vol. 63, 2026, p. 218-226.
Bakhrom Ibragimov, Nurmukhammadkhon Razzakov
This paper presents an experimental and analytical study of the erection state of large-span reinforced concrete shell structures for unique buildings. The research focuses on the stress-strain behavior of shell systems during installation, dismantling of temporary erection devices, and transition to the operational stage. Experimental modeling was carried out on large-scale models with scales of 1:10 and 1:4 for shells with spans of 48 m, 96 m, and more. Composite shells assembled from prefabricated and enlarged erection elements were investigated for different erection and dismantling sequences. The stress-strain state was evaluated under self-weight and installation loads, and the obtained results were compared with calculation data based on shell theory relations and engineering modeling procedures. It was established that the most rational dismantling sequence consists in first lowering the temporary posts and beams and then removing the forces in the temporary ties. This sequence reduces the forces in the ties by 21-34 % and ensures a more favorable stress state of the shell elements. For the studied shell configurations, labor costs were reduced by 26 %, while the weight of the erection equipment set was reduced by 2.4 times compared with traditional assembly methods. The discrepancy between experimental and calculated ultimate forces did not exceed 8.8 %. The proposed approach can be used in the design and construction practice of unique large-span buildings to improve erection safety, structural efficiency, and reliability.

Investigation of rheological properties of bitumen with calcium naphthenate additives

Aripov, Khodjiakmal — 2026-07-16T00:00:00Z

Vibroengineering Procedia, Vol. 63, 2026, p. 115-123.
Khodjiakmal Aripov, Sherzod Akhmedov, Irada Shirinzade
This study investigates the effect of calcium naphthenate obtained from alkaline waste of oil-refinery processes on the physical, mechanical, and rheological properties of BND 60/90 road bitumen. The proposed additive is considered as a waste-derived surfactant modifier aimed at improving the structural behavior and adhesion properties of bitumen used in road construction. Bitumen samples containing 5, 10, and 20 wt.% calcium naphthenate were prepared and tested in the temperature range of 40-140 °C using rotational viscometry. The results showed that calcium naphthenate affects the flow behavior of bitumen by increasing viscosity and promoting structure formation, especially at temperatures below 100 °C. The most effective modification range was found to be 5-10 wt.%, where improved adhesion to mineral materials and enhanced rheological stability were observed without excessive loss of penetration. The findings demonstrate that calcium naphthenate obtained from refinery alkaline waste can be used as a promising functional additive for bitumen modification and waste valorization.

Design and development of a multisensor wearable system for human limb motion monitoring

Kurmangazy, Maksat — 2026-07-16T00:00:00Z

Vibroengineering Procedia, Vol. 63, 2026, p. 96-102.
Maksat Kurmangazy, Anuar Maksut, Dauren Bizhanov, Nursultan Zhetenbayev, Yerkebulan Nurgizat
This paper presents the development of a wearable system for human motion monitoring based on an inertial measurement unit (IMU). The proposed device enables real-time acquisition of angular velocity, linear acceleration, and orientation parameters of a body segment. An experimental prototype was implemented using an IMU sensor, Arduino Nano, and a data recording module. Laboratory tests focused on dorsiflexion and plantarflexion movements of the ankle joint. The results demonstrate that the system can accurately capture motion parameters and reflect changes in the Pitch angle corresponding to these movements. The proposed approach can be applied in motion analysis and rehabilitation monitoring. Future work includes integration of EMG and force sensors to extend the system functionality.

Dynamic analysis and parameter optimization of combined multi-layer linear vibrating screen

Wu, Liao — 2026-07-16T00:00:00Z

Vibroengineering Procedia, Vol. 63, 2026, p. 52-58.
Liao Wu, Zhenqian Wang, Jianhui Shi, Yong Wan, Jinhao Zeng
In order to alleviate the fatigue damage caused by resonance in the combined multi-layer linear vibrating screen, this study conducted modal and harmonic response analysis using Workbench finite element analysis software. The results showed that there was a resonance risk at the 9th natural frequency. By optimizing the thickness of the side plates (increasing it by 4 millimeters), the frequency was successfully removed from the working range. This paramete optimization significantly improved the dynamic performance and reliability of the structure, providing a solid theoretical basis for design.

Stress concentration in parallel fluid-filled underground cylindrical pipes under harmonic and recorded seismic excitation

Shadmanova, Zukhra — 2026-07-16T00:00:00Z

Vibroengineering Procedia, Vol. 63, 2026, p. 35-42.
Zukhra Shadmanova, Uchkun Safarov, Hilola Djabborova, Gulnora Kasimova, Khayotjon Kurbanov
This paper investigates the dynamic stress concentration in two parallel underground cylindrical pipes filled with a compressible fluid and subjected to seismic excitation. The pipe-soil–fluid system is described as a coupled boundary-value problem within the plane dynamic theory of elasticity, in which each pipe is modelled as a thick-walled, homogeneous, isotropic, linearly elastic cylinder embedded in an infinite elastic medium and filled with an inviscid compressible fluid. The wave field around the two parallel cylinders is represented in bipolar cylindrical coordinates, and the displacement potentials are expanded in cylindrical wave functions of Bessel and Hankel type. Continuity of displacements and tractions at the outer pipe-soil interface, matching of normal velocity and pressure at the inner pipe–fluid interface, regularity at the pipe axis, and the Sommerfeld radiation condition in the surrounding medium are imposed simultaneously, leading to an infinite system of linear algebraic equations whose unknowns are obtained numerically. The model is first verified under harmonic P-, SV-, and SH-wave excitation; it is then extended to realistic seismic loading through an FFT-based transfer-function procedure, in which the harmonic solution serves as the frequency-domain Green operator. Numerical results show that the maximum dynamic stress concentration coefficient under the incident P-wave reaches 1.76 at d/D = 1.0; the limiting non-resonant distance between pipe centres increases from 5.0 m to 10.0 m as the incidence angle changes from 0° to 90°; and the presence of the internal fluid increases the seismic response by 10-20 %. Time-history analysis with the 1940 El Centro NS and 1966 Tashkent records confirms that these trends persist under realistic broadband ground motion. The novelty of the study lies in the simultaneous treatment of pipe–pipe interaction, internal fluid coupling, multiple incident wave types, and recorded seismic input within a single bipolar-coordinate analytical framework. The results are useful for the seismic design and resilience assessment of multi-line buried pipeline systems.

Intelligent microprocessor system for diagnostics and balancing of rechargeable batteries of various electrochemical types

Jarkeshev, Saken — 2026-07-16T00:00:00Z

Vibroengineering Procedia, Vol. 63, 2026, p. 124-131.
Saken Jarkeshev, Asfandiyar Orynbay, Nurgul Karymsakova, Saltanat Yusupova, Yerlan Eleukulov, Yerkebulan Nurgizat
Contemporary energy storage deployments increasingly incorporate heterogeneous cell chemistries within a single installation, yet most commercial battery management circuits remain optimized for a single electrochemical type. This paper describes a microprocessor-controlled platform capable of autonomous diagnostics and charge equalization across four battery technologies: lithium-ion NMC, lithium iron phosphate (LiFePO₄), nickel-metal hydride (NiMH), and lead-acid. The measurement front-end is a 16-bit delta-sigma converter delivering 46 μV resolution and ±1.4 mV per-cell accuracy, interfaced to an STM32F446RE ARM Cortex-M4 processor at 180 MHz. Equalization combines resistive dissipation for voltage spreads below 50 mV with a switched-capacitor network achieving above 90 % energy-transfer efficiency for larger disparities. State-of-charge tracking couples’ coulomb integration with an adaptive extended Kalman observer, maintaining accuracy within ±3 % even from a 40 % seed-error initialization. Benchtop trials on four-cell series packs of each chemistry recorded inter-cell convergence to ±5 mV within 22 min, SOC root-mean-square error below 3 %, and correct automatic chemistry classification across all laboratory sessions. The novelty of the proposed system is not in the individual use of battery diagnostics or cell balancing, which are well-established topics, but in their integration into a single microprocessor-based multi-chemistry platform capable of automatic electrochemical-type identification, chemistry-specific parameter loading, adaptive SOC/SOH estimation, and hybrid passive-active balancing. This distinguishes the proposed approach from conventional BMS solutions optimized for only one battery chemistry.

Resource utilization and performance evaluation of solid waste materials in road engineering

Wu, Enhe — 2026-07-16T00:00:00Z

Vibroengineering Procedia, Vol. 63, 2026, p. 132-136.
Enhe Wu, Zaiheng Zhou, Shaojian Liu, Lifeng Zhang, Haijun Liu
To clarify the application feasibility and practical effects of waste fly ash as a filler in asphalt pavement materials, this study selected two types of waste fly ash as the primary filler. Asphalt mastics with different fly ash contents were prepared using a high-speed melt shearing method. The interaction and compatibility between the asphalt binder and waste fly ash were characterized by scanning electron microscopy. The rheological properties of the waste-fly-ash asphalt mastics were analyzed using a dynamic shear rheometer. The influence of waste fly ash content on the pavement performance of asphalt mastic was systematically examined through three major index tests. The results indicate that replacing a portion of pure mineral filler with varying amounts of waste fly ash does not reduce the adhesion of the asphalt mastic. The addition of waste fly ash not only effectively enhances the high-temperature stability of the mastic but also improves resistance to shear deformation.

Design, modeling and experimental validation of a novel transformer-type angular displacement transducer for engineering diagnostics

Amirov, Sulton — 2026-07-16T00:00:00Z

Vibroengineering Procedia, Vol. 63, 2026, p. 137-144.
Sulton Amirov, Ulugbek Mamadaliyev, Ildar Bayanov
This paper presents the design, mathematical modeling, and experimental validation of a novel transformer-type angular displacement transducer intended for engineering diagnostics and monitoring applications. The proposed transducer is based on two horseshoe-shaped movable magnetic cores and an E-shaped fixed magnetic core with excitation and sensing windings connected in a differential configuration. The operating principle is based on a controlled variation of the effective air-gap area during angular motion, which provides a differential output signal proportional to the measured angular displacement. A mathematical model of the magnetic circuit is developed using differential equations derived from Kirchhoff’s laws, and analytical expressions are obtained for the magnetic flux and induced electromotive force as functions of the angular coordinate. The model shows that the proposed geometry ensures an extended linear static characteristic over a wide diagnostics range. The analytical results are supported by laboratory tests of the transducer prototype. The comparison between theoretical and experimental results shows a discrepancy of only 3.5-5.5 %, which confirms the adequacy of the proposed model. The developed transducer demonstrates a diagnostics range of approximately ±175° and can be recommended for control, monitoring, and measurement systems requiring a simple structure, improved linearity, and stable performance. The novelty of the proposed transducer lies in the combination of three features that, to the best of the authors’ knowledge, have not been jointly achieved in previously reported inductive or resolver-type angular sensors: (i) a variable-active-area differential magnetic circuit that ensures linearity by geometry alone, without correction electronics; (ii) a closed-form analytical model derived directly from Kirchhoff’s laws; and (iii) an experimentally validated diagnostics range of ±175°.

Analytical assessment of the reliability of the FBG multi-sensor network for monitoring CFRP structures based on the k-out-of-n model

Yussupova, Gulbakhar — 2026-07-16T00:00:00Z

Vibroengineering Procedia, Vol. 63, 2026, p. 145-152.
Gulbakhar Yussupova, Nurzhigit Smailov, Manapova Akmaral, Nagima Bakirova, Ermanova Dina, Yegemberdyeva Zaure Myktybekkyzy, Meiirkhan Satylgan, Nurbol Onalbekov
In this paper, an analytical assessment of the long-term operability of the FBG multi-sensor network used for monitoring defects in CFRP structures was carried out. The main focus of the article is devoted to assessing the reliability level of a generalized FBG sensor network, and not the effectiveness of experimental detection of a defect in a specific CFRP sample. For this reason, the study does not consider the diagnostic sensitivity of the structural health monitoring system or the probability of detecting a defect, but the functional stability of the network in the event of sensor failure. The system reliability was calculated using the k-out-of-n model, and the time-dependent reliability of an individual sensor was characterized by an exponential law. The configuration n= 120 and k= 100 was chosen as the main calculation scenario. This configuration was considered a representative redundancy model that characterized the system’s operability even in the event of a failure of about 16.7 % of the sensors. Calculations were carried out for 0-60 months for failure intensities λ= 0.005, 0.01, 0.02 and 0.05 months-1. The results showed that as the degradation intensity of an individual sensor increases, system reliability decreases dramatically. At the same time, a sensitivity analysis of k/n configurations was performed, demonstrating an engineering trade-off between redundancy and the minimum number of operating sensors. The results obtained enable the selection of the maintenance interval, sensor replacement strategy, and level of redundancy on a scientific basis when designing SHM systems based on FBG.

Comparative analysis of LQR and PID control for a reaction-wheel stabilized cube under actuator saturation constraints

Zhanay, Oralbek — 2026-07-16T00:00:00Z

Vibroengineering Procedia, Vol. 63, 2026, p. 18-23.
Oralbek Zhanay, Yerkebulan Nurgizat, Aitolkyn Rysbek, Esbol Turgambay
Reaction-wheel-stabilized Cubli-type platforms are widely used as ground testbeds for small-spacecraft attitude control, but the coupling between actuator saturation and the achievable domain of attraction has not been mapped in a unified simulation framework. This paper closes that gap using a CAD-driven Simscape Multibody pipeline (SolidWorks → Simscape → Model Linearizer → LQR/PID synthesis → saturated nonlinear validation) and reports three contributions: a head-to-head comparison of LQR and PID on an identical plant with matched saturation limits, a parametric mapping of the LQR domain of attraction against maximum motor torque τmax and a quantitative torque-margin criterion for the jump-up maneuver. For a 130 mm cube driven by a Nidec 24H BLDC motor (τmax = 0.04 N·m), LQR settles in 0.5 s – six times faster than a Simulink-tuned PID (3 s) – at 30 % lower peak flywheel velocity (85 vs. 120 rad/s). Sweeping τmax from 0.04 to 0.50 N·m expands the domain of attraction from 3° to 45° with diminishing returns above 0.20 N·m, and a 12.5× torque margin over the Nidec 24H is needed for jump-up. The framework yields directly applicable actuator-sizing rules for reaction-wheel ground testbeds and CubeSat-class attitude control.

Field investigation of structure-borne noise propagation in buildings above high-speed railway tunnels

Mei, Wenyong — 2026-07-16T00:00:00Z

Vibroengineering Procedia, Vol. 63, 2026, p. 59-65.
Wenyong Mei
Buildings constructed above high-speed railway tunnels represent an innovative model for intensive land use. However, they face significant challenges from train-induced vibrations and subsequent structure-borne noise. To investigate the propagation characteristics of this noise, a field measurement was conducted on an 18-story shear wall residential building above a railway tunnel. Vibration and indoor noise signals on different floors were synchronously recorded during train passages. The results indicate that the building's vertical vibration attenuates with increasing floor height, with the floor slab center showing a stronger response than structural columns. The indoor structure-borne noise levels within the characteristic frequency band (20-80 Hz) exhibit a “high at both ends, low in the middle” distribution, being more significant on lower floors and upper floors compared to middle floors. Within the 20-100 Hz characteristic band, a relatively stable transfer relationship exists between the structure-borne noise sound pressure level and the floor vibration velocity level, although significant deviations occur at structural or acoustic resonance frequencies. Influenced by the indoor background noise, the overall linear correlation between vibration and noise is not strong on some floors. This study reveals the propagation patterns of vibration and structure-borne noise in overbuilding structures, providing data and theoretical references for targeted vibration and noise reduction design.

Modern instruments for detection and quantitative assessment of hidden rail cracks

Zhurynova, Zhanna Omarkhanovna — 2026-07-16T00:00:00Z

Vibroengineering Procedia, Vol. 63, 2026, p. 153-159.
Zhanna Omarkhanovna Zhurynova, Ivan Sergeyevich Bondar, Dinara Tanashbekovna Aldekeyeva, Kulzira Kumargalievna Nurakhmetova, Tamara Darkembaevna Digarbaeva, Anton Anatolyevich Deinichenko
The development of high-speed and heavy-haul railway traffic leads to an increase in dynamic stresses in rails, resulting in the formation of hidden fatigue cracks. Such defects are among the most dangerous because they cannot be detected by visual inspection and failure occurs suddenly without warning. In recent years, the primary direction of railway safety improvement has shifted from mere defect detection to quantitative assessment of defect severity and prediction of the rail residual life. This paper analyzes modern rail non-destructive testing (NDT) instruments, including ultrasonic, eddy current, magnetic, acoustic emission, and intelligent diagnostic systems. Their operating principles, sensitivity to various defect types, inspection depth, and fields of application are considered. Particular attention is given to phased array ultrasonic testing and high-speed inspection vehicles providing continuous in-motion monitoring of track condition. A methodology for quantitative assessment of hidden crack severity based on the fracture energy criterion and the stress intensity factor is proposed. A calculation model is developed to determine the probability of rail failure considering defect parameters, stress state, and traffic conditions. A calculation example for a standard R65 rail is presented. The results show that integrating multi-channel defectoscopy with mathematical residual life prediction reduces the probability of rail fracture by more than three times. The obtained relationships can be applied for transitioning from periodic inspections to a risk-based track maintenance system.

Semantic retrieval of Uzbek seismic safety regulations

Ishkobilov, Farrukh — 2026-07-16T00:00:00Z

Vibroengineering Procedia, Vol. 63, 2026, p. 227-231.
Farrukh Ishkobilov, Abdulatif Meyliev, Mironshoh Ortikov, Javlon Ibragimov, Umida Turaeva, Elmurod Jumaev
This study presents a semantic retrieval approach for Uzbek seismic safety regulations and engineering documents. The proposed system combines paragraph-level indexing with two retrieval models, a classical TF-IDF baseline and a FastText-based subword embedding model, to improve access to relevant regulatory and technical text units in a morphologically rich language environment. A specialized corpus was compiled from seismic engineering and safety documentation and segmented into paragraphs for fine-grained semantic search. The retrieval performance was evaluated on 100 domain-specific queries using Precision@5, Recall@5, Mean Average Precision (MAP), and Mean Reciprocal Rank (MRR). The experimental results show that the FastText model outperformed TF-IDF across all major metrics, achieving Precision@5 = 0.7444 and Recall@5 = 0.6875, compared with 0.6017 and 0.5418, respectively. The observed improvement was statistically significant according to paired t-test analysis (t= 15.1372, p< 0.001). The findings indicate that subword-based semantic modeling improves retrieval quality for Uzbek seismic safety documentation and can support faster access to relevant engineering regulations and compliance information.

Partial discretization solution for flexure of a circular plate

Kyrykbayev, Batyrkhan — 2026-07-16T00:00:00Z

Vibroengineering Procedia, Vol. 63, 2026, p. 232-238.
Batyrkhan Kyrykbayev, Auezkhan Turdaliev, Roza Koilybayeva, Algazy Zhauyt
This paper presents an analytical solution for the axisymmetric flexure problem of a rotationally symmetric circular plate using the method of partial discretization of differential equations. The plate is considered under transverse loading and radial boundary action, which lead to a fourth-order differential equation describing the deflection of the plate. Since direct analytical integration of the governing equation may be difficult for non-uniform loading and boundary conditions, the partial discretization approach is applied to transform the original problem into a more convenient analytical-discrete form. Explicit expressions are obtained for the plate deflection, rotation angle, bending moments, and transverse shear force. The derived solution makes it possible to evaluate the influence of radial boundary load on the deformation behavior of the circular plate. Numerical examples and graphical results demonstrate that increasing the radial load leads to a systematic increase in deflection and internal force factors. The obtained results confirm the effectiveness of the proposed method and show its applicability for engineering analysis of circular plates and thin-walled structural elements subjected to axisymmetric loading.

Optimization of nozzle geometry for improving bottomhole cleaning efficiency in roller cone drilling

Nazarbekova, Dilobar — 2026-07-16T00:00:00Z

Vibroengineering Procedia, Vol. 63, 2026, p. 239-245.
Dilobar Nazarbekova, Bekzod Nurtoev
This paper develops an engineering-analytical framework that links roller cone bit nozzle geometry directly to the specific hydraulic energy Es required per metre drilled. A submerged free-jet decay relation, a cuttings-particle force balance and a Shields-type incipient-motion criterion are coupled to define the minimum wall-jet velocity for cuttings lift-off, which is imposed as a hard constraint in a constrained optimization of the nozzle diameter dn, inclination angle θ and stand-off distance h. The problem is solved by parametric grid search and five representative configurations are compared. The recommended optimum (dn= 18 mm, θ= 20°, h= 50 mm) lowers Es from 35.95 to 5.04 MJ/m (an 86 % reduction) and raises the predicted rate of penetration from 11.3 to 22.0 m/h (+95 %) relative to a conventional pressure-based arrangement, at the same flow rate and number of nozzles. A one-at-a-time sensitivity study confirms that the optimum is robust to the model calibration constants. Geometry-based redistribution of hydraulic energy is thus more effective, and more sustainable, than pressure-based intensification of the flushing flow.

A reduced-order diagnostic framework for pantograph-contact wire vibration response and reliability-oriented assessment

Yakubov, Mirjalil — 2026-07-16T00:00:00Z

Vibroengineering Procedia, Vol. 63, 2026, p. 66-75.
Mirjalil Yakubov, Ildar Bayanov, Solmaz Kalbiyeva
Pantograph–contact wire interaction is a complex distributed dynamic problem that usually requires multi-degree-of-freedom or finite-element modelling for detailed design verification. This paper does not attempt to replace such high-fidelity models. Instead, it proposes a reduced-order diagnostic framework for preliminary assessment of dominant vibration response, contact force variation, and reliability-oriented indicators of railway overhead contact lines. The contact network is first interpreted as a distributed multi-degree-of-freedom system, after which modal reduction is used to obtain a simplified representation of the dominant contact-wire vibration mode. To avoid an excessive simplification of pantograph-contact wire interaction, a two-coordinate reduced model is introduced, including the vertical displacement of the pantograph head and the dominant displacement of the contact wire. Wind excitation, stiffness degradation, and electrical-thermal effects are considered only through their influence on contact force stability, contact loss probability, and degradation-related reliability indicators. The limitations and possible errors caused by model-order reduction are explicitly discussed. An illustrative parametric example demonstrates how stiffness degradation changes natural frequency, contact force fluctuation, probability of contact loss, and preliminary reliability indicators. The proposed framework is intended for early-stage diagnostics and sensitivity analysis rather than full-scale design validation.

Predictive modeling of aluminum alloy fluidity as a function of Germanium content

Tursunbaev, Sarvar — 2026-07-16T00:00:00Z

Vibroengineering Procedia, Vol. 63, 2026, p. 160-165.
Sarvar Tursunbaev, Nigora Rizaeva, Kamola Aripova, Ravshan Tashmatov, Alisher Zukhritdinov, Sardor Uktamov
The study presents a theoretical and experimental analysis of the variation in the fluidity of aluminum alloys – one of their key casting properties – under the influence of germanium and silicon. Based on experimental investigations, aluminum-based alloys were modified with different amounts of germanium and silicon, and the optimal modification level was determined through mathematical modeling. Initially, under laboratory conditions, aluminum casting alloys were alloyed with germanium at concentrations of 1 %, 2 %, and 3 % (relative to the charge), while 5 % silicon was added to each sample. The prepared melts were cast into standard spiral molds designed to evaluate fluidity. After solidification and removal from the molds, the lengths of the samples were measured, and a relationship between germanium content and fluidity was established in the form of a graph. Based on the obtained experimental data, the effect of germanium content on alloy fluidity was mathematically modeled. The modeling process was carried out using the Lagrange interpolation method. The resulting function allows for the theoretical prediction of the influence of varying germanium concentrations on the fluidity of the alloy.

Evaluation of a road section performance in North Kazakhstan

Teltayev, Bagdat — 2026-07-16T00:00:00Z

Vibroengineering Procedia, Vol. 63, 2026, p. 166-171.
Bagdat Teltayev, Yerbol Aitbayev, Arystan Massanov, Azamat Zhaisanbayev, Aizhan Muta
In this work using a mobile laboratory the operational condition of a road section (length: 47 km) of the “Ekaterinburg-Almaty” road located in the Kostanay region (northern Kazakhstan) was carried out. During the survey of the road section the main indicators as roughness, rut depth, total length of longitudinal and transverse cracks, areas of asphalt concrete pavement with a block cracking, elasticity modulus of the pavement structure have been evaluated. Intensity and composition of traffic is carried out by the MetroCount 5600.