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This study focuses on a double-tower, double-plane prestressed concrete cable-stayed bridge with a span arrangement of 75+130+365+130+75 m. A full-bridge finite element model was developed using Midas Civil, and a monitoring system was established to track main girder alignment, cable forces, and structural stresses. A phased control and monitoring strategy is implemented: alignment control is prioritized during the cantilever casting stage, while cable force and stress control take precedence during the closure stage. Monitoring results indicate that the alignment of the completed bridge's main girder is smooth, with cable force deviations controlled within 10 %, and stresses in both the main girder and pylons remaining within safe limits. This study integrates dynamic control and monitoring strategies, offering practical references for the construction control of similar bridges.

This paper presents an inertia channel design methodology for a hydraulic damper dedicated to high-speed rail applications. By theoretically analyzing how dimensional parameters of the inertia channel influence the damping force of the hydraulic mount, the calculation methods for both friction losses and local losses are elaborated in detail. Integrating specific design targets, the required inertia-channel dimensions are derived. The study demonstrates that the proposed approach can markedly accelerate the design process of hydraulic dampers and substantially cut research-and-development costs.

This paper systematically studies the characteristics of building vibration and structural noise caused by train operation in view of the vibration and noise problems specific to the railway canopy complex in the integrated development of stations and cities through field measurement. The results show that the vibration energy of the floor slab is concentrated in the medium and low frequency band of 20-80 Hz and directly leads to the main peak of indoor noise in the 40-80 Hz band, with significant coherence between the two, confirming that the “vibration-sound” coupling mechanism is the main source of noise; Interior decoration can effectively improve the acoustic environment quality by reducing the reverberation time. This study reveals the intrinsic connection between vibration and noise and demonstrates that “vibration control of sound” is the fundamental approach to addressing such problems. The research results can provide key theoretical basis and engineering guidance for the optimal design and environmental control of the superstructure.

This paper studies a large-span low-pier continuous rigid frame bridge using Midas Civil to model a full-bridge simulation. It assesses two force-adjustment measures during construction: permanent counterweights at side-span cantilever ends and reverse thrusting at mid-span free ends. Monitoring data shows good agreement between measured pier forces/displacements and simulations, proving the feasibility of measures in improving the bridge’s force conditions.

In response to the drawbacks of existing vibrating screens, such as fixed vibration parameters, lack of adjustability, and poor adaptability, this study proposes a new type of vibrating screen with multiple adjustable vibration parameters. By modifying the dimensions of the rubber springs, the amplitude can be adjusted; by increasing or decreasing the number of components such as side plates, the screening width can be adjusted; by adding spacer blocks to the frame, the inclination angle of the screen surface can be adjusted; and by altering the installation position of the vibration motors, the vibration direction angle can be adjusted. This new vibrating screen features a simple and reliable structure, is capable of adapting to different working conditions, and provides a technical reference for innovative designs of vibrating screens.

To address the issues of insufficient low-frequency damping and high-frequency stiffening in magnetorheological mount systems, this paper proposes a novel mount structure combining a bell plate with a squeeze model. Through establishing a lumped parameter model, conducting magnetic field simulations using Ansys, and integrating dynamic characteristic analysis, the study concludes that: 1) The bell plate structure significantly reduces high-frequency dynamic stiffness by 35.89 %, effectively suppressing high-frequency stiffening; 2) The squeeze channel markedly enhances low-frequency dynamic stiffness and loss angle, thereby resolving the issues of insufficient low-frequency damping and stiffness.

Reliable 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.

In high-intensity focused ultrasound (HIFU) therapy, the differing signs of the acoustic velocity-temperature coefficients in multilayered heterogeneous tissues (such as fat-muscle) lead to inherent systematic errors in traditional single-frequency ultrasound thermometry methods and make them susceptible to motion artifacts. Therefore, this study proposes a non-invasive temperature reconstruction theory based on the relative phase difference of dual-frequency ultrasound. By establishing a multiphysics model coupling nonlinear acoustic wave propagation and the Pennes bioheat transfer equation, and using the finite-difference time-domain (FDTD) method for simulation, the performance of this method was systematically evaluated in a three-layer tissue (skin-fat-muscle) model. Simulation results show that under 20 seconds of HIFU irradiation, the focal temperature rise reached 35.3 °C; the root-mean-square error of the temperature reconstructed by the dual-frequency phase difference method was only 0.076 °C, while the error of the traditional single-frequency time-of-flight method was as high as 8.531 °C, representing an accuracy improvement of approximately 99.1 %. Furthermore, the sensitivity of the dual-frequency method to overall axial tissue displacement was only 22.2 % of that of the single-frequency method, demonstrating excellent resistance to motion artifacts. This study provides a theoretical basis and a new design paradigm for developing high-precision and robust non-invasive thermometry systems for HIFU.