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The severe vibration of BHA directly affect the drilling efficiency, borehole trajectory, and wellbore quality. Therefore, it is crucial for developing dynamic mechanics of drill string system by studying the mechanical behavior of BHA. In this paper, considering the continuity condition of double-span drill collar, the expression of lateral vibration of drill collars is firstly obtained by using the assumption mode method. Then, the lateral vibration equation of double-span drill collar is derived by Lagrange equation. Finally, a self-programming model is established based on dynamic mechanics of drill string system, the lateral vibration characteristics of double-span drill collar in four different types of BHA is further determined by the fourth-order Runge-Kutta algorithm. It is obviously found that the lateral vibration is enhanced with increasing the length of drill collar; the rotation speed of BHA, weight on bit (WOB), and the size of stabilizer have a significant influence on the lateral vibration of drill collar. In the practical application, the lengths of the first-span and the second-span drill collar are given as 10 and 19 m, respectively; and the stabilizer diameter approached to bit diameter is recommend in practical gas drilling engineering; under WOB of 10–40 kN, the rotation speed of the drilling string should be controlled nearby 60 r/min. The theoretical investigation is a guidance for structure design of BHA and optimization of drilling parameter.

As the speed of high-speed trains increases, the vehicle’s lateral stability steadily deteriorates. There have been observations of abnormal vibrations in the tail car, particularly on certain sections of the railway line. This study built a high-speed train aerodynamic simulation model for a three-car consist, and a multibody dynamics simulation model for an eight-car consist based on numerical simulations of train aerodynamics and multibody dynamics. It investigated both steady and unsteady aerodynamic loads, flow field characteristics, and the dynamic performance of vehicles under varied aerodynamic loads at 400 km/h. The results indicate that the aerodynamic loads generated during high-speed train operation exhibit highly unsteady characteristics. Steady aerodynamic loads have a relatively minor impact on the vehicle’s dynamic performance, whereas unsteady loads exert a more significant influence. Under unsteady aerodynamic forces, the tail car experiences severe lateral vibrations. The lateral stability index, displacement, velocity, and acceleration of the tail car under unsteady conditions were measured at 2.26, 7.54 mm, and 0.53 m/s2, respectively. These values represent increases of over 17.71%, 148.84%, and 111.24%, respectively, compared to the steady loads. Large oscillation amplitudes result in more significant lateral displacements and accelerations of the vehicle. This phenomenon is a crucial factor contributing to the “tail swing” effect observed in high-speed trains. This study emphasizes the importance of considering unsteady aerodynamic effects in assessing the lateral stability of high-speed trains and highlights the significance of mitigating the adverse impacts of such dynamic responses, particularly in the tail car.

Aiming at the problems of inefficient mitigation of the lateral vibration of high-speed elevator cars, which results in low riding comfort, this paper introduces the electromagnetic active rolling guide shoes and incorporates the sky-hook damping control strategy into the high-speed elevator structure. On this basis, it adopts an optimization algorithm based on Sparrow Search Algorithm (SSA) to adjust the parameters of the lateral vibration controller, thereby reducing the amplitude of the lateral vibration and controlling it within the human comfort range. Specifically, this paper first incorporates electromagnetic active rolling guide shoes into the vibration reduction device of the high-speed elevator car. Based on the motion characteristics of lateral vibration, a mathematical model is established in which the sky-hook damping control strategy is introduced. Then, a simulation model is built, and the damping parameters of the controller are optimized using the SSA, resulting in effective control of the lateral vibration amplitude of the high-speed elevator car. Simulations demonstrate that the lateral vibration control model of the high-speed elevator car, optimized by SSA, achieves lower amplitudes within the frequency range of 1–2 Hz compared to the results obtained by the Genetic Algorithm (GA), demonstrating the effectiveness of SSA in optimizing the damping parameters of the car controller. Finally, the simulation results are compared with the measured data, and the research findings indicate that the proposed method for lateral vibration control of the car can effectively suppress the lateral vibration amplitude.

The dataset provided in this paper includes the lateral vibration data obtained by on-site vibration tests on an 18-story timber-concrete hybrid building, which was completed in 2017 and is located within the University of British Columbia campus in Vancouver, Canada. Aiming at evaluating vibration properties such as natural periods, damping ratios, and mode shapes, microtremor measurement (i.e., ambient vibration test) and human-powered excitation tests were conducted from March 27th to 29th, 2023. Lateral velocity data of the building were collected using eight servo velocity sensors, type VSE-15D, and a data acquisition system, type SPC-52, composed of an A/D converter and a DC amplifier. The voltage data picked up by the sensors was first converted to digital data and then transferred to the hard disk drive in a laptop through Ethernet. In the microtremor measurements, the lateral vibration in the longitudinal and the transverse directions of the test building were measured with three types of locations of the sensors in order to evaluate the vibration behavior along the height of the building and its torsional behavior. The human-powered excitation tests were carried out by pushing walls by eight persons in accordance with the fundamental frequency in the transverse direction, aiming at obtaining larger amplitude than with microtremor. The dataset is useful to deepen the understanding of the dynamic properties of tall timber-concrete hybrid buildings and encourage reasonable structural design and health monitoring of tall mass timber buildings.

A semi-floating cable-stayed bridge can swing longitudinally to absorb seismic energy in an earthquake for the purpose of reducing structural response. However, the large transverse (lateral) seismic response of such large-span cable-stayed bridges must be controlled to avoid severe bridge damage and ensure train safety. This study investigates the dynamic response and associated damping mechanism of a coupled high-speed rail (HSR) vehicle and cable-stayed bridge system subjected to various ground motions. A comprehensive vehicle–track–bridge interaction system is first established. Then, the dynamics of a semi-floating cable-stayed bridge-HSR vehicle system equipped with magnetorheological bearings (MRBs) and fluid viscous dampers (FVDs) is examined with various inputs of near-fault (NF) pulse-type, NF non-pulse-type, and far-field (FF) ground motions. To effectively mitigate the bridge internal force response and enhance train running safety, the transverse and longitudinal FVDs need to be concurrently utilized along with MRBs. This research presents a novel mitigation approach for simultaneously reducing the transverse vibrations of cable-stayed bridge and the derailment risk of running train. [ABSTRACT FROM AUTHOR]

Observing the vibration of the elevator ropes in an elevator shaft is a difficult task. Although several methods of observing the displacement using image processing or laser displacement meters and then estimating the vibration through an observer or a Kalman filter have been developed, it is difficult to install sensors because of the movement of the elevator car and the thinness of the rope as an observation target. Therefore, in this study, we focus on a pulley called a compensating sheave that does not change its lateral position as the car and ropes move. The horizontal vibration of the ropes causes the compensating sheave to vibrate in the vertical direction. A method of estimating the horizontal vibration from this vertical vibration using arc length calculations and a short-time fast Fourier transform is proposed. First, the vertical vibration of the compensating sheave is distributed to the various mode responses based on the predominant frequency of the vertical vibration. The mode-decomposed vertical vibration is then converted into a horizontal mode response using an arc length relational expression. Analysis of seismic response data confirms that the proposed method can estimate the 1st, 2nd, and 3rd horizontal mode responses from the vertical vibration.

This paper gives a mathematical formulation for the transverse resonance of thermoelastic nanobeams that are simply supported and compressed with an initial axial force. The nonlocal elasticity concept is used to analyze the influence of length scale with the dual-phase-lag (DPL) heat transfer theory. The nanobeam is due to a changing thermal load and moves in one direction at a constant speed. The governing motion equation for the nonlocal Euler-Bernoulli (EB) beam hypothesis can also be derived with the help of Hamilton's principle and then solved by means of the Laplace transform technique. The impacts of nonlocal nanoscale and axial velocity on the different responses of the moving beam are investigated. The results reveal that phase delays, as well as the nonlocal parameter and external excitation load, have a substantial impact on the system's behavior.

Lateral vibrations of the tower of a horizontal axis wind turbine is lightly damped and is vulnerable to induced vibration loads from wind. Such induced vibration load can decrease the fatigue life and increase the maintenance costs. Active vibration control using generator torque has been studied in previous research works but, there is a trade-off between reducing the lateral oscillations of the tower and fluctuations of output power, since any fluctuations in generator torque, in turn, causes fluctuations in the output power In this research, we illustrate a way that actively controls the lateral vibrations of the tower by using the generator torque but also simultaneously reduces fluctuations in the output power. We first, introduced a novel intelligent fuzzy torque control by measuring the lateral displacements of the tower and would receive feedback in the form of rotor speed error and its time derivative. On the basis of using this intelligence torque controller, we then introduced three-pitch control strategies to reduce output power fluctuations by considering the sliding mode theory. The simulation results demonstrate that the second strategy is extremely effective for reducing both lateral tower displacement and output power fluctuation.

Since the mid-2000 s, longitudinal tinning has been applied to concrete pavements of expressways to improve the comfort and safety of road vehicle users. However, in certain longitudinal tinning sections, lateral vibrations occur during driving, which poses a safety hazard. This paper analyzes the cause behind this problem and proposes a longitudinal texturing specification that can minimize lateral vibration. To perform this analysis, the accelerations of driving vehicles and the degree of lateral vibration transmitted to panels in the vehicles were evaluated for each longitudinal texture applied in South Korea. Structural analysis was also conducted for the lateral force and moment according to the tire tread profile and longitudinal texturing specifications using the finite element method. In addition, field investigation, indoor drivability evaluation, and field application were performed to evaluate the optimal longitudinal texturing specification. The results indicate that the texture designated as 2 × 3 × 19 mm is the optimal longitudinal texture on hardened concrete pavement. However, because this specification is difficult to apply to fresh concrete, 3 × 3 × 16 mm is proposed as the optimal longitudinal texture owing to its excellent performance in the panel survey and in structural analysis.

The critical wind speed of overturning is one of indices for the safety evaluations of railway vehicles against crosswind. The critical wind speed of overturning is defined as the wind speed when wheel loads on the upwind side becomes zero, and is often evaluated by the “RTRI’s detailed equation”. In the RTRI’s detailed equation, the lateral vibration inertia force of car bodies is considered as one of the acting forces affecting overturning. The inertia force can be obtained from the product of the lateral vibration acceleration and the mass, and the lateral vibration acceleration is assumed from past running test results. However, there are differences in position, direction and situation between the lateral vibration acceleration measured in the running tests and the lateral vibration acceleration in the calculation model of the RTRI’s detailed equation. In this paper, model experiments in a wind tunnel were conducted to clarify the effects of the differences with respect to the lateral vibration acceleration. Next, vehicle dynamics simulation was implemented to calculate the lateral vibration acceleration that occurs at the center of gravity of a car body under strong crosswinds. The results showed that the critical wind speed of overturning can be calculated accurately by using the simulation results of the lateral vibration acceleration that occurs at the center of gravity of the car body under strong crosswinds. In addition, a new method is proposed to estimate the lateral vibration acceleration using the track displacement data. Finally, when the critical wind speed of overturning was calculated assuming typical commuter vehicles, the wind speed obtained from the proposed new method was up to 2m/s higher than the wind speed obtained from the assumed equation in the RTRI’s detailed equation.

The aeronautical gear has the characteristics of light weight and low rigidity. It is easy to take lateral vibration under the internal excitation of the gear pair. It is necessary to study the inherent characteristics of the lateral vibration of the aeronautical gear for the design of the aeronautical gear. The flexibility of the gear web， the stiffness of the bearing and the gear meshing stiffness are considered， the finite element model of the gear rotor is established by the finite element software for rotor dynamics named Samcef， and the natural frequency， vibration mode and the critical speed of the high-speed gear rotor system are calculated. Compared with the inherent characteristics of the gear rotor system without consideration of flexibility， it is shown that the frequency values and modes of the lateral vibration of the gear rotor system can be obtained by considering the flexibility of the gear web. Without considering the flexibility of gears， the frequency and mode shapes of lateral vibration of gears can′t be obtained.

Curved pedestrian bridges are important urban infrastructure with the desired adaptability to the landscape constraints and with aesthetic benefits. Pedestrian bridges feature thin cross-sections, which provide sufficient load capacities but lead to low natural frequencies that make the bridges susceptible to vibration under pedestrian excitation. This study investigates the lateral vibration of a curved bridge with a small radius down to 20 m, proposes an approach to mitigate the lateral vibration of bridges with large curvatures using distributed multiple tuned mass dampers (MTMD), and conducts in-situ bridge tests to evaluate the vibration mitigation performance. The lateral vibration was investigated through in-situ tests and finite element analysis as well as the code requirements. The key parameters of the distributed MTMD system were improved by strategically selecting the mass ratio, bandwidth, center frequency ratio, and damper number. The results showed that the curved bridge was subjected to significant lateral vibration due to the coupling of torque and moment, and the recommended design parameters for the studied bridge were derived, i.e., the total mass ratio is 0.02, bandwidth is 0.15, center frequency ratio is 1.0, and damper number is 3. The proposed approach effectively improves the deployment of MTMD for lateral vibration control of the curved bridge. The field tests showed that the vibration was reduced by up to 82% by using the proposed approach.

Vibration measurement techniques can be categorized into contact-type and non-contact-type techniques. These types of techniques can add mass-loading to a lightweight structure resulting in the negative performance of a structure, because sensors, high contrast speckles or targets should be mounted on a structure. Moreover, non-contact-type vibration measurement techniques have only been tested to detect vibrations using a single camera. As the vibrations occurring at the opposite sides of a rotating structure in a region of interest (ROI) can be different from each other. For 3-dimensional (3D) vibration measurement, the same position in videos acquired from two cameras should be used. Because the videos acquired by two cameras placed perpendicular to the structure can be used to detect the vibrations in the x-direction as well as y-direction. In this study, an epipolar line-based corresponding point selection on a rotating cylindrical structure was performed, to extract the same ROIs from videos recorded by two cameras. A fundamental matrix was constructed by using the targets attached on the structure and in the background. The coordinates of the mid-pixel of the ROI in a video acquired by one camera was used to determine the epipolar line for the same ROI in the video acquired by another camera. Then an edge-based vibration measurement technique was applied to measure the vibration in the extracted ROIs. The results were used to reconstruct a 3D vibration signal. The 3D vibration measurement results can be used to effectively recognize the deformations resulting in the negative performance of a structure.