Computers & Structures最新文献

{"title":"Dynamic fundamental solution of dipole for Kirchhoff plate on Winkler-Pasternak foundation","authors":"","doi":"10.1016/j.compstruc.2024.107498","DOIUrl":"10.1016/j.compstruc.2024.107498","url":null,"abstract":"<div><p>The Method of Fundamental Solution (MFS) for the thin plate resting on the Winkler-Pasternak elastic foundation under dynamic loading is proposed in this work. In traditional MFS, the double-source method is utilized with two free variables including the locations of source pint. In order to construct MFS with few free parameters, the main aim of this paper is to deduce two fundamental solutions for a concentrated force and a dipole of thin plate resting on the elastic foundation with damping by Laplace transform technique. The behaviours and performances of fundamental solutions are observed comprehensively. Time domain numerical results are obtained by the Durbin’s inverse method and the behaviours of fundamental solutions are observed comprehensively. The main novelty of this paper is the derivation of Laplace transformed fundamental solutions of the dipole of a Kirchhoff plate resting on the Winkler-Pasternak elastic foundation with the damping factor and comparisons have been made between Kirchhoff plate and Reissner/Mindlin plate theories under dynamic loadings. In order to show the accuracy of this methodology, numerical comparisons between the present work and<!--> <!-->either analytical solutions or finite element<!--> <!-->solutions are presented. Excellent agreements with both analytical solution and finite element method solution are observed.</p></div>","PeriodicalId":50626,"journal":{"name":"Computers & Structures","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141963758","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Non-intrusive reduced-order modeling for nonlinear structural systems via radial basis function-based stiffness evaluation procedure","authors":"","doi":"10.1016/j.compstruc.2024.107500","DOIUrl":"10.1016/j.compstruc.2024.107500","url":null,"abstract":"<div><p>This paper presents a new radial basis function-based stiffness evaluation procedure developed in the framework of nonlinear, and non-intrusive reduced-order modeling. For structural nonlinear systems, a stiffness evaluation procedure (STEP) and its variants use a cubic polynomial for evaluating nonlinear stiffness coefficients and have been developed as non-intrusive reduced-order models (ROM) using data obtained from numerical simulation model. In this paper, we propose using a radial-basis function (RBF) instead of the cubic polynomials on evaluating nonlinear stiffnesses. As the RBF shows a good performance for approximating nonlinearities, the efficiency and robustness of the ROM are substantially enhanced in a non-intrusive manner. In particular, the proposed R-STEP ROM can be constructed for elastoplastic analysis without any additional treatments. Various numerical examples verify the performance of the proposed R-STEP ROM comparing with the STEP methods and commercial finite element software, ABAQUS.</p></div>","PeriodicalId":50626,"journal":{"name":"Computers & Structures","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141910850","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A contact-based constitutive model for the numerical analysis of masonry structures using the distinct element method","authors":"","doi":"10.1016/j.compstruc.2024.107499","DOIUrl":"10.1016/j.compstruc.2024.107499","url":null,"abstract":"<div><p>This study presents a robust contact constitutive model in the distinct element method (DEM) framework for simulating the mechanical behavior of masonry structures. The model is developed within the block-based modeling strategy, where the masonry unit is modeled as deformable blocks with potential crack surfaces in the middle of the bricks, while the mortar joints are defined as zero-thickness interfaces. The modeling strategy implements multi-surface plasticity with damage mechanics, including a tension cut-off, Coulomb failure criterion, and an elliptical compressive cap for the damage in tension, shear, and compression, respectively. Two new features are introduced in this contact model: a piecewise linear softening function for strength degradation in tension and shear and a hardening/softening function to phenomenologically define the compressive damage of masonry composite into the unit-mortar interface. The constitutive model is implemented in commercial DEM software using the small displacement configuration and validated against material and experimental tests on masonry walls subjected to constant pre-compression and monotonically increasing in-plane load. The experimental and numerical results regarding the force-displacement relationship and damage pattern produced by the proposed constitutive model are compared and critically discussed, demonstrating the capability of DEM coupled with the suitable constitutive law in simulating the behavior of masonry structures.</p></div>","PeriodicalId":50626,"journal":{"name":"Computers & Structures","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0045794924002281/pdfft?md5=702e913655f44f4fb0c92cd3a8faf337&pid=1-s2.0-S0045794924002281-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141910851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A direct differentiation method based on forward recursive formulation for flexible multibody system sensitivity analysis","authors":"","doi":"10.1016/j.compstruc.2024.107465","DOIUrl":"10.1016/j.compstruc.2024.107465","url":null,"abstract":"<div><p>Sensitivity analysis plays a significant role in the dynamic optimization of flexible multibody systems. The forward recursive formulation (FRF) is widely used for the dynamic modeling of multibody systems. However, it has not yet been extended to sensitivity analysis. In this paper, a new direct differentiation method is developed based on FRF for flexible multibody systems sensitivity analysis. The recursive nature of FRF allows for the Jacobian derivatives to be derived recursively, with detailed matrix expressions provided to facilitate implementation in computer code. The validity and correctness of the presented direct sensitivity analysis method based on FRF are verified by numerical examples. Besides, a modified staggered direct scheme is presented to improve the efficiency of the sensitivity analysis. In this scheme, different update strategies are adopted by different components of the tangent stiffness matrix for the implicit integrator, which balances the iteration performance and the additional computational cost. The presented scheme is compared with two conventional schemes through three examples. It demonstrates that the presented scheme can significantly improve the computational efficiency of the sensitivity analysis, particularly for complex problems, when the appropriate update strategies are employed.</p></div>","PeriodicalId":50626,"journal":{"name":"Computers & Structures","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141910853","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A wavelet-based denoising method for pipeline dent assessments","authors":"","doi":"10.1016/j.compstruc.2024.107497","DOIUrl":"10.1016/j.compstruc.2024.107497","url":null,"abstract":"<div><p>Strain-based assessments of dents in buried steel oil and gas pipelines are commonly carried out in practice. Dent signals obtained from the caliper inspection tool contain noises that can have a large impact on the accuracy of the estimated strain. This paper proposes a novel wavelet-based denoising method for dent signals based on the overcomplete expansion with the corresponding dictionary constructed using the stationary and hyperbolic wavelet transforms. The proposed method is validated based on noise-free and noisy dent signals generated from elasto-plastic finite element analyses of a pipe segment subjected to an indenter and shown to be more effective than the commonly used wavelet transform-based hard- and soft-thresholding methods in terms of the root mean square error and the accuracy of the effective dent strain estimated from the denoised signal. The proposed method is further employed to denoise 42 real dent signals from in-service pipelines to illustrate its effectiveness and potential practical application to facilitate strain-based dent assessments.</p></div>","PeriodicalId":50626,"journal":{"name":"Computers & Structures","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0045794924002268/pdfft?md5=f23f3f49b6c4fba9d261d0f6eaba1a7e&pid=1-s2.0-S0045794924002268-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141910852","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A numerical framework for modeling 3D electrostrictive dielectric elastomer actuators","authors":"","doi":"10.1016/j.compstruc.2024.107495","DOIUrl":"10.1016/j.compstruc.2024.107495","url":null,"abstract":"<div><p>In this paper, we have developed a numerical framework to investigate the effects of the electrostriction phenomenon on the deformations of three-dimensional dielectric elastomer actuators with complex geometries and inhomogeneous displacement fields at finite strains. The finite element method has been used to solve the governing equations. In this investigation, we adopt one of the most complete constitutive equations with regard to the electrostrictive behavior of dielectric elastomers which is capable of analyzing general three-dimensional states of deformation. The terms emerging in the tangent stiffness matrix as a result of the electrostrictive model are fully derived in this study. The implementation of the finite element modeling is conducted via an in-house computer code. Three three-dimensional actuators, namely a bending actuator, a buckling actuator, and a torsional actuator are selected to demonstrate the capabilities of the numerical framework. In conclusion, we have proved that the electrostriction phenomenon is effective in terms of improving the performance of dielectric elastomer actuators and in lowering their operating voltage. Moreover, the relationship of the diagonal entries of the permittivity tensor and the left Cauchy-Green tensor have been depicted on the deformed bodies of the actuators.</p></div>","PeriodicalId":50626,"journal":{"name":"Computers & Structures","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141891667","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Computational framework for a family of methods based on stress-constrained topology optimization","authors":"","doi":"10.1016/j.compstruc.2024.107493","DOIUrl":"10.1016/j.compstruc.2024.107493","url":null,"abstract":"<div><p>This study presents a general computational framework for topology optimization under constraints related to various engineering design problems, including: reliability analysis, low-cycle fatigue assessment, and stress limited analysis. Such a framework aims to facilitate comprehensive engineering design considerations by incorporating traditional constraints such as displacement and stress alongside probabilistic assessments of fatigue failure and the complex behaviors exhibited by structures made of elastoplastic material. The framework's amalgamation of diverse analytical components offers engineers a versatile toolkit to address intricate design challenges. Notably, the inclusion of reliability analysis introduces a probabilistic perspective, transforming conventional design constraints into random parameters, thereby enhancing the robustness of the design process.</p><p>Key to the framework's efficacy is its implementation using MATLAB mathematical computing software, leveraging the platform's efficient code execution and object-oriented programming paradigm. This choice ensures an intuitive and potent environment for designers and researchers, facilitating seamless adaptation across various engineering applications. Additionally, the proposed previously by the Authors algorithm for the topology optimization is extended by adaptive strategy allowing for efficient adjustment of an amount of material removed at individual optimization step.</p><p>The presented framework is offering a comprehensive and integrated approach to address multifaceted design challenges while enhancing design robustness and efficiency.</p></div>","PeriodicalId":50626,"journal":{"name":"Computers & Structures","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0045794924002220/pdfft?md5=54d93361ed8a873db90e2f4b67c3407a&pid=1-s2.0-S0045794924002220-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141891581","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A hybridization of growth optimizer and improved arithmetic optimization algorithm and its application to discrete structural optimization","authors":"","doi":"10.1016/j.compstruc.2024.107496","DOIUrl":"10.1016/j.compstruc.2024.107496","url":null,"abstract":"<div><p>This paper proposes an improved hybrid growth optimizer (IHGO) to solve discrete structural optimization problems. The growth optimizer (GO) is a recent metaheuristic that has been successfully used to solve numerical and real-world optimization problems. However, it has been found that GO faces challenges with parameter tuning and operator refinement. We also noticed that the formulation of GO has some drawbacks, which may cause degradation in optimization performance. Compared to the original GO, four improvements are introduced in IHGO. First, the learning phase of GO is improved to avoid useless search and reinforce exploration. To do this, the exploration phase of an improved metaheuristic called IAOA is incorporated into the learning phase of GO. Second, the replacement strategy of GO is modified to prevent the loss of the best-so-far solution. Third, the hierarchical structure of GO is modified. Fourth, some adjustments are made to the reflection phase of GO to promote the exploitation of promising regions. To demonstrate the performance of the proposed IHGO, four discrete optimization problems of skeletal structures are provided. The results are compared with those of the original GO and some other metaheuristics in the literature. The source codes of IHGO are available at <span><span>https://github.com/K-BiabaniHamedani/Improved-Hybrid-Growth-Optimizer</span><svg><path></path></svg></span>.</p></div>","PeriodicalId":50626,"journal":{"name":"Computers & Structures","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141891796","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fluid-structure coupling analysis in liquid-filled containers using scaled boundary finite element method","authors":"","doi":"10.1016/j.compstruc.2024.107494","DOIUrl":"10.1016/j.compstruc.2024.107494","url":null,"abstract":"<div><p>In this study, a semi-analytical model is developed to investigate the fluid-structure coupling characteristics of liquid sloshing in an elastic rectangular container subjected to horizontal external excitation based on the scaled boundary finite element method (SBFEM) for the first time. The fluid inside the container is assumed to be incompressible, inviscid and irrotational, with the hydrodynamic pressure chosen as independent nodal variable in the governing equations. The container walls are considered as cantilever beams. The coupled fluid-structure system is initially divided into the structural domain and fluid domain, after which the SBFEM is employed to obtain the governing equations for each sub-domain. In the framework of the SBFEM, only the boundary of each sub-domain, rather than the entire computational domain, needs to be meshed and discretized. This method reduces the spatial dimension of the problem by one and offers an efficient approach to model the computational domain, while allowing for analytical formulations to be derived for the internal of the domain, resulting in an accurate description of the field variables. The fundamental equation of the entire coupled fluid-structure system is then assembled by performing the equilibrium condition and compatibility condition to ensure the balance of interaction forces at the interface between container walls and the liquid. The free vibrations analysis of the fluid-structure coupling system is solved by utilizing the generalized eigenvalue problem, and the transient dynamic response is determined using the synchronous solution algorithm in conjunction with the implicit-implicit scheme of the Newmark method. To validate the excellent accuracy and stability of the proposed formulation, several numerical examples are presented to investigate the free vibration and transient dynamic characteristics for the fluid-structure coupling problem. The obtained results show good agreement with reference solutions available in the literature. Additionally, the effects of geometrical and material parameters on the system responses are examined and discussed.</p></div>","PeriodicalId":50626,"journal":{"name":"Computers & Structures","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141891582","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A global-discretized semi-analytical formulation in polar coordinate system for the wave characteristics in multi-layer cylindrical waveguides","authors":"","doi":"10.1016/j.compstruc.2024.107487","DOIUrl":"10.1016/j.compstruc.2024.107487","url":null,"abstract":"<div><p>Ultrasonic guided waves are widely applied in health monitoring of slender structures. Being different from the well-known semi-analytical finite element method (SAFE), the global-discretized semi-analytical formulation (GDSA) exactly satisfies all the continuity and boundary conditions accurately while has improved computational efficiency, but is only applicable to the plate-like problems described in the Cartesian coordinate system currently, which is not applicable to the cylindrical waveguide. In the present work, the polar coordinate system is therefore introduced into the GDSA formulation to improve the computational efficiency of calculating the dispersion relation in a multi-layer cylindrical waveguide without loss of accuracy. The characteristic equations of the unit layer are derived from the principle of virtual work. The involved matrices are explicitly derived in the form of Kronecker product to reduce the dimension of the matrices to be evaluated and a reduced Boolean matrix is introduced to avoid the singularity problem caused by the trivial radial displacement of the central point. The dispersion curves of a steel wire are firstly analyzed and are verified in comparison with the analytical solutions solved from the Pochhammer-Chree equations. Taking the steel wire having a surface corrosion as a two-layer case example, the dispersion curves are obtained based on the quadratic eigenvalue equation. It is found that the cut-off frequency of the F(1,2) mode is sensitive to corrosion, having potential to detect corrosion of hidden cable wires.</p></div>","PeriodicalId":50626,"journal":{"name":"Computers & Structures","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141891583","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}