Yuanjun Dai^1,2,*, Xin Wei¹, Baohua Li¹, Cong Wang¹, Kunju Shi¹

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.2, pp. 337-348, 2024, DOI:10.32604/fdmp.2023.042434

Abstract To study the impact of the trailing-edge wear on the vibrational behavior of wind-turbine blades, unworn blades and trailing-edge worn blades have been assessed through relevant modal tests. According to these experiments, the natural frequencies of trailing-edge worn blades −1, −2, and −3 increase the most in the second to fourth order, the fifth order increases in the middle, and the first order increases the least. The damping ratio data indicate that, in general, the first five-order damping ratios of trailing-edge worn blades −1 and trailing-edge worn blades −2 are reduced, and the first five-order damping ratios of trailing-edge worn… More >

Amthal Hakim¹, Wael Slika^1,*, Rawan Machmouchi¹, Adel Elkordi²

Structural Durability & Health Monitoring, Vol.17, No.3, pp. 175-194, 2023, DOI:10.32604/sdhm.2022.023027

Abstract Corrosion of reinforcing steel in concrete elements causes minor to major damage in different aspects. It may lead to spalling of concrete cover, reduction of section’s capacity and can alter the dynamic properties. For the dynamic properties, natural frequency is to be a reliable indicator of structural integrity that can be utilized in non-destructive corrosion assessment. Although the correlation between natural frequency and corrosion damage has been reflected in different experimental programs, few attempts have been made to investigate this relationship in forward modeling and/or structural health monitoring techniques. This can be attributed to the limited available data, the complex… More >

Xiaoyan Teng¹, Qiang Li¹, Xudong Jiang^2,*

CMES-Computer Modeling in Engineering & Sciences, Vol.135, No.3, pp. 2479-2496, 2023, DOI:10.32604/cmes.2023.023110

Abstract A smooth bidirectional evolutionary structural optimization (SBESO), as a bidirectional version of SESO is proposed to solve the topological optimization of vibrating continuum structures for natural frequencies and dynamic compliance under the transient load. A weighted function is introduced to regulate the mass and stiffness matrix of an element, which has the inefficient element gradually removed from the design domain as if it were undergoing damage. Aiming at maximizing the natural frequency of a structure, the frequency optimization formulation is proposed using the SBESO technique. The effects of various weight functions including constant, linear and sine functions on structural optimization… More >

Xiaojun Huang^1,2, Liaojun Zhang^1,*, Renyu Ge², Hanbo Cui², Zhedong Xu²

CMES-Computer Modeling in Engineering & Sciences, Vol.132, No.1, pp. 23-41, 2022, DOI:10.32604/cmes.2022.019765

Abstract In the current research, an effective differential quadrature method (DQM) has been developed to solve natural frequency and vibration modal functions of circular section beams along radial functional gradient. Based on the high-order theory of transverse vibration of circular cross-section beams, lateral displacement equation was reconstructed neglecting circumferential shear stress. Two equations coupled with deflection and rotation angles were derived based on elastic mechanics theory and further simplified into a constant coefficient differential equation with natural frequency as eigenvalue. Then, differential quadrature method was applied to transform the eigenvalue problem of the derived differential equation into a set of algebraic… More >

Tareq Al-hababi^1,2, Nizar Faisal Alkayem^1,3, Li Cui⁴, Shixiang Zhang⁵, Cong Liu⁶, Maosen Cao^1,2,*

Structural Durability & Health Monitoring, Vol.16, No.1, pp. 15-35, 2022, DOI:10.32604/sdhm.2022.020418

Abstract A significant amount of research is concerned with dynamic modal parameters for damage detection of structural conditions due to their simplicity in use and feasibility. However, their use for damage detection should be performed with special attention, particularly in operational and environmental conditions subjected to temperature changes. Beams in construction industries experience different loading types, such as temperature changes leading to crack initiation and propagation. Changed physical and dynamic properties such as natural frequencies and mode shapes indicate that damage has occurred within the structures. In this study, vibration analysis of cantilever and cantilever simply supported beams has been carried… More >

Jian Gong¹, Lingzhi Xie^1,2,*, Yongxue Li¹, Zhichun Ni³, Qingzhu Wei³, Yupeng Wu⁴, Haonan Cheng⁵

Journal of Renewable Materials, Vol.10, No.1, pp. 33-51, 2022, DOI:10.32604/jrm.2021.016262

Abstract Based on the recent development of renewable energy utilization technology, in addition to centralized photovoltaic power plants, distributed photovoltaic power generation systems represented by building-integrated photovoltaic systems are frequently employed for power supply. Therefore, in the architectural design, the double-glass photovoltaic module used in the integrated photovoltaic building system puts forward a higher load-bearing capacity requirement and the corresponding simplified method of carrying capacity check. This article focuses on the simplified method of checking the bearing capacity of the four-sided simply supported double-glass photovoltaic module. First, the principle of equivalent stiffness is used to calculate the effective thickness. Then, the… More > Graphic Abstract

Deepak Kumar Singh^*

Sound & Vibration, Vol.55, No.3, pp. 253-262, 2021, DOI:10.32604/sv.2021.011627

Abstract The analysis of spliced column has been carried out to detect optimum location of providing splices in the column. In the present work, static and dynamic (free vibration) analyses of spliced column have been done by randomising the location of splicing. A symmetrical four storey steel framed building has been modelled, analysed and designed for loads (dead, live and earthquake loads) recommended by Indian Codal provisions using Staad.Pro. The critical column at each floor level is identified based on axial force (AF), bending moment (BM) and shear force (SF). The total 16 models of spliced columns have been designed and… More >

A. M. Abd-Alla^1,*, Hanaa Abu-Zinadah², S. M. Abo-Dahab³, J. Bouslimi^4,5, M. Omri⁶

CMC-Computers, Materials & Continua, Vol.68, No.2, pp. 1485-1504, 2021, DOI:10.32604/cmc.2021.012586

Abstract This article is aimed at describing the way rotation and magnetic field affect the propagation of waves in an infinite poroelastic cylindrical bone. It offers a solution with an exact closed form. The authors got and examined numerically the general frequency equation for poroelastic bone. Moreover, they calculated the frequencies of poroelastic bone for different values of the magnetic field and rotation. Unlike the results of previous studies, the authors noticed little frequency dispersion in the wet bone. The proposed model will be applicable to wide-range parametric projects of bone mechanical response. Examining the vibration of surface waves in rotating… More >

Jaafar Hallal^1,2,3,*, Mohammad Hammoud^2,3, Mahmoud Fakih^2,3,4, Ali Hallal^2,3

Sound & Vibration, Vol.54, No.4, pp. 225-236, 2020, DOI:10.32604/sv.2020.011513

Abstract The vibrations behavior analysis is an essential step in the mechanical design process. Several methods such as analytical modelling, numerical analysis and experimental measurements can be used for this purpose. However, the numerical or analytical models should be validated through experimental measurements, usually expensive. This paper introduces an inexpensive smartphone as an accurate, non-intrusive vibrations’ behavior measurement device. An experimental measurement procedure based on the video processing method is presented. This procedure allows the measurement of the natural frequencies and the mode shapes of a vibrating structure, simply by using a smartphone built-in camera. The experimental results are compared to… More >

Jianping Sun¹, Jan Niederwestberg^2,*, Fangchao Cheng¹, Yinghei Chui²

Journal of Renewable Materials, Vol.8, No.3, pp. 319-328, 2020, DOI:10.32604/jrm.2020.08696

Abstract Cross laminated timber (CLT) panels, which are used as load bearing plates and shear panels in timber structures, can serve as roofs, walls and floors. Since timber is construction material with relatively less stiffness, the design of such structures is often driven by serviceability criteria, such as deflection and vibration. Therefore, accurate vibration and elastic properties are vital for engineered CLT products. The objective of this research is to explore a method to determine the natural frequencies of orthotropic wood plates efficiently and fast. The method was developed based on vibration signal processing by wavelet to acquire the effective sample… More >