Article
Engineering, Civil
Xutao Sun
Summary: In this study, the dynamic stiffness method incorporating the Wittrick-Williams algorithm is used to analyze the natural frequencies of a cracked beam, while investigating the influence of a crack on the algorithm's components. The study shows that the crack affects the discretization of the structure, but the crack element itself does not directly contribute to the second component of the algorithm.
THIN-WALLED STRUCTURES
(2021)
Article
Engineering, Civil
Xiang Liu, Yu Li, Yuliang Lin, J. Ranjan Banerjee
Summary: A spectral dynamic stiffness (SDS) model for plate assemblies stiffened by beams is proposed, with a sufficient generality to cover a wide range of applications. The method involves developing SDS formulations for different beam stiffeners using modified Fourier series and superposing their matrices onto those of plate assemblies. The accuracy and versatility of the proposed theory are extensively validated using the software ANSYS.
THIN-WALLED STRUCTURES
(2021)
Article
Engineering, Mechanical
Xiang Liu, Zhaoming Lu, Sondipon Adhikari, YingLi Li, J. Ranjan Banerjee
Summary: This paper proposes two significant developments of the Wittrick-Williams (W-W) algorithm, which combines dynamic stiffness (DS) model and the W-W algorithm for accurate and efficient wave propagation analysis. The method is applied to hexagonal honeycomb lattice structures and compared with finite element method (FEM) results. It is shown that the proposed method is at least two orders of magnitude more computationally efficient and provides accurate eigenvalues and eigenmodes.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2022)
Article
Engineering, Civil
J. R. Banerjee, A. Ananthapuvirajah, X. Liu, C. Sun
Summary: The free vibration behavior of coupled axial-bending Timoshenko beams was studied by developing the dynamic stiffness matrix and utilizing solution techniques to derive expressions for axial and bending displacements as well as bending rotation. The importance of axial-bending coupling effects and shear deformation in free vibration behavior was discussed with significant conclusions drawn.
THIN-WALLED STRUCTURES
(2021)
Article
Engineering, Civil
Yulin Luo, Carol A. Featherston, David Kennedy
Summary: Damage modelling is crucial for preliminary structural design and non-destructive damage detection. This paper proposes a novel hybrid method that combines an exact strip model with a finite element model to analyze changes in natural frequencies of plates caused by arbitrarily aligned cracks. The crack is represented as a rotational spring with additional rotational freedoms. The method is validated by comparing with published results and used to investigate the effects of varying crack parameters.
THIN-WALLED STRUCTURES
(2023)
Article
Computer Science, Interdisciplinary Applications
Md Imran Ali, M. S. Azam, V Ranjan, J. R. Banerjee
Summary: The free vibration characteristics of Sigmoid Functionally Graded Material (S-FGM) Levy-type plates were investigated using the Dynamic Stiffness Method (DSM), with a proposed method that is accurate and simple to compute natural frequencies and mode shapes of the plates. The results can be used as benchmark solutions for further investigation of FGM plates.
COMPUTERS & STRUCTURES
(2021)
Article
Mechanics
Zhiwei Huang, Yufeng Xing, Yahe Gao
Summary: This method presents a new approach for predicting stiffness of periodic beam-like structures based on the selfequilibrium equation of the unit cell. The effective stiffness matrix of a periodic heterogeneous beam is explicitly formulated, and six normalization constraints are introduced to determine the unique solution of the selfequilibrium equation of the unit cell. A standard finite element formulation for calculating warping displacements is derived using the principle of the minimum potential energy.
COMPOSITE STRUCTURES
(2021)
Article
Engineering, Mechanical
Xingzhuang Zhao, Peter Chang
Summary: This study focuses on the free and forced vibrations of the DBS-ISEL, providing analytical and numerical solutions. The asymptotic deflections of the two beams converge to static deflections in damped vibrations. The intermediate elastic support effectively modulates the deflections of the beams.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2021)
Article
Engineering, Mechanical
Xiang Liu, Xiao Liu, Sondipon Adhikari, Shengwen Yin
Summary: This paper proposes an efficient and reliable eigenvalue solution technique for analytical stochastic dynamic stiffness (SDS) formulations of beam built-up structures with parametric un-certainties. The method combines the Wittrick-Williams (WW) algorithm, the Newton iteration method and numerical perturbation method to extract eigensolutions from SDS formulations, demonstrating robustness and efficiency through numerical examples.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2022)
Article
Chemistry, Multidisciplinary
Manish Chauhan, Pawan Mishra, Sarvagya Dwivedi, Minvydas Ragulskis, Rafal Burdzik, Vinayak Ranjan
Summary: In this paper, the dynamic stiffness method was used to study the out-of-plane natural vibration of a thin orthotropic plate. The obtained results can serve as benchmark solutions for comparing the natural frequencies of orthotropic plates.
APPLIED SCIENCES-BASEL
(2022)
Article
Mathematics
Xiang Liu, Shaoqi Qiu, Suchao Xie, Jnan Ranjan Banerjee
Summary: This paper extends the Wittrick-Williams (W-W) algorithm to connect any combinations of line and point nodes, providing a general method for hybrid dynamic stiffness models. The proposed direct constraint method and extended W-W algorithm simplify the modeling and solution process, while maintaining numerical stability in complex built-up structures.
Article
Acoustics
Yuhao Zhao, Jingtao Du, Yilin Chen, Yang Liu
Summary: This research focuses on the effects of nonlinear vibration absorbers in beam structures and their impact on dynamic behavior, adjusting parameters of NVAs can optimize vibration suppression of the beam structure.
JOURNAL OF VIBRATION AND CONTROL
(2022)
Article
Construction & Building Technology
Wei Xiang, Xin Li, Lina He
Summary: This paper presents a modified differential quadrature finite element method (DQFEM) that combines the standard DQFEM with the virtual boundary spring technique to easily implement arbitrary elastic restraints. The method provides a unified solution for flexural vibrations of composite laminates under general elastic boundary combinations. Numerical examples demonstrate the accuracy, stability, and reliability of the method, and the new results obtained for elastically constrained laminates can serve as reference values for future research.
Article
Chemistry, Multidisciplinary
Mu-Xuan Tao, Zi-Ang Li, Qi-Liang Zhou, Li-Yan Xu
Summary: This study analysed the equivalent flexural stiffness of composite frame beams and developed a fitting formula to evaluate it, taking into account the influence of rotational constraint at beam ends and cracked section in negative moment region. The proposed formula's validity was demonstrated through comparison with existing design formulas and further verified through nonlinear finite element simulations, showing its practical utility in engineering design.
APPLIED SCIENCES-BASEL
(2021)
Article
Computer Science, Interdisciplinary Applications
J. R. Banerjee
Summary: This paper derives the frequency dependent mass and stiffness matrices of bar and beam elements and establishes their equivalency with the dynamic stiffness matrix, paving the way for future research to include damping in dynamic stiffness research. The results permit the application of the Wittrick-Williams algorithm to compute the exact natural frequencies of structures comprising bar and beam elements.
COMPUTERS & STRUCTURES
(2021)
Article
Engineering, Multidisciplinary
Keyu Zhu, Xitao Zheng, Jing Peng, Jiaming Sun, Ruilin Huang, Leilei Yan
Summary: This paper discusses the influence of multiple impacts on the compression strength of honeycomb sandwich structures with composite face sheets. It is found that the size of the impactor affects the turning point of the compression strength. Additionally, high impact energy leads to damage in the bottom face sheet and reduces the overall compression strength.
COMPOSITES PART B-ENGINEERING
(2024)
Article
Engineering, Multidisciplinary
Danqian Wang, Yanfei Yue, Jueshi Qian
Summary: Magnesium Potassium Phosphate Cement (MKPC) as a binder for steel rebars shows improved corrosion resistance when subjected to carbonation, due to the increase in pH and the formation of a more protective oxide film.
COMPOSITES PART B-ENGINEERING
(2024)
Article
Engineering, Multidisciplinary
Zhibin Li, Wenyu Wang, Pengcheng Xue, Xingyu Wei, Jian Xiong
Summary: This work proposes a design approach and manufacturing method for carbon fiber reinforced plastic (CFRP) corrugated sandwich truncated cones (CSTC) to improve their anti-debonding ability and ensure reliability. The study establishes theoretical models for CSTCs' stiffness and failure modes, which are verified through experiments and finite element analysis (FEA). The research reveals the effect of geometric parameters on failure modes and performs an optimal design for CSTC structures. The findings have significant implications for the design and application of lightweight CSTCs in constructions, such as launch vehicle adapters.
COMPOSITES PART B-ENGINEERING
(2024)
Article
Engineering, Multidisciplinary
Mingyu Zhang, Lei Chu, Jiahua Chen, Fuxun Qi, Xiaoyan Li, Xinliang Chen, Deng-Guang Yu
Summary: This review summarizes the different structures and construction methods of fibrous membranes with asymmetric wettability. It also reviews the biological applications of these membranes and suggests future challenges.
COMPOSITES PART B-ENGINEERING
(2024)
Article
Engineering, Multidisciplinary
E. Mofakhami, L. Gervat, B. Fayolle, G. Miquelard-Garnier, C. Ovalle, L. Laiarinandrasana
Summary: This study investigates the effects of fibre concentration on the mechanical response of welded glass-fibre-reinforced polypropylene (GF-PP). Experimental observations reveal a significant reduction in weld ratio, up to 60%, indicating a decreased strength compared to the bulk material. Increasing fibre content in the welded material results in a decrease in stress at break and strain at the maximum stress. The use of DIC technique and X-ray microtomography further confirms the localized strain amplification in the welded zone due to the significant increase in fibre density.
COMPOSITES PART B-ENGINEERING
(2024)
Article
Engineering, Multidisciplinary
Emad Pourahmadi, Farjad Shadmehri, Rajamohan Ganesan
Summary: This research compares the mechanical properties of laminates manufactured using automated fiber placement and conventional autoclave curing methods. The results show that laminates manufactured using automated fiber placement have a lower interlaminar shear strength compared to laminates reconsolidated using autoclave curing. A finite element simulation method is proposed to quantitatively analyze these differences.
COMPOSITES PART B-ENGINEERING
(2024)
Article
Engineering, Multidisciplinary
Johnny Jakobsen, Benny Endelt, Fahimeh Shakibapour
Summary: This study proposes a new bolted/pinned joining method for composite applications, which improves load transfer by introducing a patch-type reinforcement. Experimental results demonstrate significant improvements in both static and fatigue load conditions compared to existing methods. Finite element simulations highlight the advantage of this method, as it creates a more efficient load-transferring mechanism through different stress distributions.
COMPOSITES PART B-ENGINEERING
(2024)
Article
Engineering, Multidisciplinary
Gisele G. Cintra, Janine D. Vieira, Daniel C. T. Cardoso, Thomas Keller
Summary: This paper proposes a novel approach to assess multi-crack behavior in layered fiber-polymer composites. The generated Compliance and R-curves provide useful insights into understanding the multiple delamination process and allow for separate evaluation of strain energy release rate (SERR) for each crack. The developed cohesive zone model successfully simulates the failure process zone of three parallel cracks, showing good agreement between the numerical model and experimental results.
COMPOSITES PART B-ENGINEERING
(2024)
Article
Engineering, Multidisciplinary
Renil Thomas Kidangan, Sreedhar Unnikrishnakurup, C. Krishnamurthy, Krishnan Balasubramaniam
Summary: The induction heating process can accurately identify fiber orientation and stacking order, making it a valuable tool for large-area inspection and quality control in manufacturing fiber-reinforced composites.
COMPOSITES PART B-ENGINEERING
(2024)
Article
Engineering, Multidisciplinary
Sungjun Hwang, Yousoo Han, Douglas J. Gardner
Summary: Bleached Kraft pulp, unbleached Kraft pulp, and old corrugated cardboard pulp are suitable for producing cellulose nanofibril suspensions. Spray drying is a fast, simple, cost-effective, and scalable drying method. Spray-dried cellulose nanofibrils can be used as reinforcing materials in polypropylene matrices. The particle size of cellulose nanofibrils affects the material properties.
COMPOSITES PART B-ENGINEERING
(2024)
Article
Engineering, Multidisciplinary
Mehdi Mahdavi, Abbas Zolfaghari
Summary: This study aims to improve the recovery forces of shape memory polymers (SMPs) through material extrusion additive manufacturing. By using glass fiber (GF) as reinforcement and manufacturing multi-layer composite specimens, it was found that PLA with 6.62% GF exhibited the best recovery force, which was further optimized through annealing heat treatment.
COMPOSITES PART B-ENGINEERING
(2024)
Review
Engineering, Multidisciplinary
Xiang Ao, Antonio Vazquez-Lopez, Davide Mocerino, Carlos Gonzalez, De-Yi Wang
Summary: The vulnerability of natural fibers to heat and fire poses a significant challenge for their substitution of traditional fiber reinforcements in composite materials. Natural fiber/polymer composites (NFCs) are regarded as potential candidates for engineering applications due to their environmental friendliness and low-impact sourcing. Thus, appropriate approaches need to be implemented to enhance the fire safety of NFCs. This review summarizes and discusses the latest understanding of flammability and thermal properties of natural fibers, with a special focus on their interaction with polymer matrix in fire behavior. Additionally, the latest developments in flame-retardant approaches for NFCs are reviewed, covering both flame retardancy and fire structural integrity. Finally, future prospects and perspectives on fire safety of NFCs are proposed, providing insights into further advancements of NFCs.
COMPOSITES PART B-ENGINEERING
(2024)
Article
Engineering, Multidisciplinary
Cheng Wang, Siqi Huo, Guofeng Ye, Bingtao Wang, Zhenghong Guo, Qi Zhang, Pingan Song, Hao Wang, Zhitian Liu
Summary: The demand for multifunctional, transparent epoxy resin with superior dielectric, mechanical, and fire-safety performances is increasing in modern industries. Researchers have developed an epoxidized, phosphaphenanthrene-containing poly(styrene butadiene styrene) (ESD) for advanced fire-safe epoxy resin, which maintains high transparency and improves UV-blocking property. The addition of 10 wt% ESD results in improved mechanical properties, decreased dielectric constant and loss, and outperformance compared to other fire-safe epoxy resins. This research provides an effective method for developing multifunctional flame-retardant epoxy resin.
COMPOSITES PART B-ENGINEERING
(2024)
Article
Engineering, Multidisciplinary
Bo Pang, Heping Zheng, Zuquan Jin, Dongshuai Hou, Yunsheng Zhang, Xiaoyun Song, Yanan Sun, Zhiyong Liu, Wei She, Lin Yang, Mengyuan Li
Summary: This study develops an internal superhydrophobic material (ISM) using waste denitrification fly ash, which maintains stable hydrophobicity under harsh conditions of use and does not rely on expensive fluor-based surface modifications. The synthesized ISM has excellent matrix strength, strong waterproof properties, and retains superhydrophobicity even at damaged or friction interfaces.
COMPOSITES PART B-ENGINEERING
(2024)
Article
Engineering, Multidisciplinary
Meirbek Mussatayev, Qiuji Yi, Mark Fitzgerald, Vincent K. Maes, Paul Wilcox, Robert Hughes
Summary: Real-time monitoring of carbon fibre composites during Automated Fibre Placement (AFP) manufacturing remains a challenge for non-destructive evaluation (NDE) techniques. This study designed a directional eddy-current (EC) probe to evaluate the detectability of out-of-plane wrinkles. Experimental evaluations and finite element modeling were conducted to better understand the relationship between eddy-current density and defect detection. The findings suggest that the probe configuration with an asymmetric driver coil and differential pickup coils shows the best capability for wrinkle detection.
COMPOSITES PART B-ENGINEERING
(2024)