Journal of Vibroengineering

Journal of Vibroengineering, (in Press).Zhihui Yu, Chuan Lin, Chaohui Huang, Yifan Huang, Jiaman LuoVibration signals from high-voltage circuit breakers (HVCB) typically contain complex background noise, and traditional fault diagnosis methods often neglect the temporal relationship between vibration signals and fault characteristics. To address these issues, an IMCEEMDAN-TSG fault diagnosis model based on vibration signals is proposed. First, Pearson correlation coefficient filtering is combined to improve the Complete Ensemble Empirical Mode Decomposition with Adaptive Noise (IMCEEMDAN) for adaptive multi-resolution analysis, which effectively separates the intrinsic mode function (IMF), thereby filtering out noise contained in the signal, suppressing mode aliasing, and preserving key signal features. Secondly, a TSG hybrid algorithm is constructed by combining the Temporal Convolutional Network (TCN) embedded with the Self-Attention Mechanism (SAM) and the Gated Recurrent Unit (GRU). This architecture facilitates the parallel feature extraction of multi-channel IMF and the capture of temporal relationships, thereby deeply modeling temporal dependencies and revealing the dynamic evolution of vibration signals. Experimental results demonstrate that the proposed model achieved a fault diagnosis accuracy of 100 % on the HVCB simulation datasets, surpassing the traditional Convolutional Neural Network (CNN) by 19.07 %. Furthermore, compared with conventional algorithms, significant improvements were observed across all classification metrics, providing an accurate and reliable solution for the mechanical fault diagnosis of HVCB.

Journal of Vibroengineering, (in Press).Shuping Chen, Jinwen WuThe dynamic interaction of adjacent high-rise structures on deep soft soils was systematically investigated using advanced three-dimensional finite element modeling. Parametric analyses considered varying building spacings (10-40 m), foundation types, and soil stiffness values. Compared with isolated soil-structure interaction (SSI), the structure-soil-structure interaction (SSSI/DCI) scenario increased peak interstory drift ratios by up to 38 % and amplified maximum foundation displacement by 25 % for the closest building pairs. Dynamic coupling also resulted in a reduction of fundamental natural frequencies by as much as 15 %. The influence of soil flexibility was found to be critical; structures on softer soils experienced stronger interaction and greater seismic response amplification. The findings provide quantitative evidence and practical guidance for the seismic design of high-rise clusters in urban environments with deep soft ground.

Journal of Vibroengineering, (in Press).Pengfei Su, Hui Guo, Wei Wang, Hao LiSegmental assembled piers have gained increasing attention in bridge engineering due to their superior construction efficiency, shortened construction periods, and reduced on-site wet work. However, their application in high-seismic-intensity regions remains limited because the mechanical performance of segment joints is generally weaker than that of conventional monolithic piers. This concern is particularly critical for high-speed railway bridges, which demand exceptional structural stability and seismic safety. To address this issue, energy dissipation bars were introduced into a segmental assembled round-end hollow pier to enhance its seismic resilience. A nonlinear finite element model was developed and validated against experimental results to ensure the reliability of the numerical approach. Based on the validated model, the effects of key design parameters of the energy dissipation bars were systematically investigated, and dynamic time-history analyses were conducted to evaluate seismic responses under different earthquake motions. The results demonstrate that increasing the sectional contribution ratio of the energy dissipation bars markedly improves the lateral resistance, energy dissipation capacity, and loading-unloading stiffness of the pier. However, this enhancement also results in larger residual drift angles, indicating a trade-off between seismic robustness and post-earthquake recoverability. Compared with the diameter and quantity of the bars, their arrangement shows a relatively limited influence on seismic performance. Moreover, the vibration mitigation effectiveness becomes increasingly significant with rising peak ground acceleration (PGA), achieving reduction rates exceeding 60 %. Nevertheless, severe plastic deformation and damage to the energy dissipation bars were observed under strong earthquakes, which indirectly amplify residual displacements. Additionally, the pier exhibits substantially stronger seismic responses under near-field ground motions than under far-field motions. In particular, near-field pulse-like earthquakes significantly amplify the pier-top displacement, suggesting that special design considerations are necessary when deploying such piers in near-fault regions. This study provides important insights into the seismic performance and design optimization of segmental assembled hollow piers for high-speed railways, offering valuable theoretical support and practical guidance for their application in seismic regions.

Journal of Vibroengineering, (in Press).Xiao Meng, Mei WangReliable operation of main mine ventilation fans is essential for mine safety and production continuity. In many mines, fan condition is still judged against fixed vibration limits that do not account for changes in airflow and pressure, which can lead to frequent false alarms and ambiguous interpretation of mechanical degradation. This paper proposes a maintenance-event-constrained vibration health index (MEC-HI) that combines operating-condition modelling with long-term residual vibration analysis using SCADA-level measurements. A linear regression model is first fitted to relate bearing RMS vibration velocity to airflow, differential pressure and motor electrical quantities during confirmed healthy operating phases. The model is then used to estimate the expected vibration level and to compute condition-normalised residual vibration. Positive residuals exceeding a statistically derived tolerance are smoothed and accumulated over time within segments separated by major maintenance events, and the cumulative index is reset after bearing replacement. Unlike many health-indicator studies that rely on high-frequency waveforms or fault-specific feature engineering, the proposed framework targets practical deployment when only routine RMS and operating tags are archived. The approach is demonstrated using a three-year dataset (24,672 operating hours) from an axial-flow main fan in a large underground copper mine. The case study shows that MEC-HI captures the onset and progression of bearing degradation more clearly than raw RMS trends and suppresses load-driven false alarms, while remaining implementable with routinely available SCADA measurements. The framework can be extended to other ventilation fans and rotating machinery operating under strongly varying loads.

Journal of Vibroengineering, (in Press).Cabrera Yerry, Velasquez Sergio, Campos Alfredo, Prada Engels, Hernandez PedroThe present study analyzes the causes of increased vibration in Francis-type hydroelectric generators, focusing on the rotor-stator assembly and the rotor support structure (rotor spider), and considering installation and operational performance. Through comprehensive analysis of vibration histories, visual and topographic inspections, roundness measurements, alignment and magnetic-center surveys, and finite element modeling (FEM) under nominal speed and runaway speed conditions (81.8 and 175 rpm), the principal causes of elevated vibration were identified. Key findings include: fatigue fracture of the bases supporting the polar rim support block; loss of rotor-stator magnetic centering (polar rim descent up to 20 mm); and loss of rotor roundness (maximum deviation 1.7 mm). FEM revealed stress concentrations in the original design that exceed the yield strength of A-36 steel and fatigue safety factors below 1 in the critical region. These conditions produce structural imbalance and intermittent vertical forces that increase vibration – particularly during start/stop transients and in pass-through bands of natural frequencies. Bearing issues, the thrust ring flatness and the original alignments/centricities are ruled out as primary causes. The study provides a solid technical basis for corrective interventions and redesign proposals aimed at reducing vibration and improving unit reliability, and constitutes a methodological and practical reference for diagnosing and solving vibration problems in similar hydraulic machines.