Abstract: Publication date: April 2020Source: Advances in Engineering Software, Volume 142Author(s): Giovanni Pipitone, Giorgio Barone, Alessandro PalmeriAbstractDouble-skin façades (DSFs), usually designed for aesthetic reasons or energy saving purposes, have been recently proposed as an alternative mean of passive control, able to reduce the effects of dynamic actions on building structures. This paper presents a novel approach to optimise their design as distributed vibration absorbers (VAs). Four key design parameters have been chosen to represent the façade, namely its flexural stiffness and viscous damping ratio, along with the stiffness of the elements connecting the façade to the primary structure. The optimisation is achieved by minimising the variance of the building’s dynamic response, conveniently computed in a stochastic framework. Solutions are obtained using genetic algorithms (GAs), including nonlinear constraints limiting the relative displacements between primary and secondary structures. Computational efficiency of the optimisation procedure is largely improved, compared to previous works, by characterising the seismic action as a stationary random process, fully defined by some closed-form analytical expressions for the power spectral density (PSD) function consistent with target response spectra. Four configurations of double-skin façades have been analysed, including single and multi-panel layouts, spanning one to six storeys, and their efficiency has been quantified. Results are compared with those obtained directly in the time domain by numerical integration of the equations of seismic motion for a suite of recorded accelerograms, showing a good level of consistency.

Abstract: Publication date: April 2020Source: Advances in Engineering Software, Volume 142Author(s): Ammar Taher Al-Sayegh, Ehsan Noroozinejad FarsangiAbstractThe objective of this work is to develop and test a new data structure, which takes advantage of the latest programming technology to build interactive structural engineering modeling software that is robust, efficient, portable, modular, expandable, and easy to use. The data structure proposed is composed of a collection of matrices that describe both the geometrical properties and the topological adjacency information of the structural model, as well as the section, material, loading, and fixity attributes of the structural elements. This data structure is dubbed the Adjacency Matrix Data Structure (AMDS). There are eight matrices in the AMDS, each capturing the details of one type of structural entity or attribute: Vertex, Edge, Face, Group, Section, Material, Load, and Fixity. The design of the AMDS allows it to excel in terms of efficiency and speed when used in a matrix-based programming environment, such as MATLAB. The final outcome called “BASYS-MTB” is a structural modeling and visualization MATLAB Toolbox that is a demonstration implementation of the AMDS as the underlying data structure. The toolbox, which can serve as a preprocessor, solver, and postprocessor, employs the object-oriented programming capabilities in MATLAB to create and manipulate numerical and graphical objects. This system offers engineers and researchers with limited programming expertise a structural modeler that can be easily customized to their requirements using their existing knowledge in MATLAB.

Abstract: Publication date: April 2020Source: Advances in Engineering Software, Volume 142Author(s): Manh-Hung Ha, Quang-Viet Vu, Viet-Hung TruongAbstractIn this article, an efficient methodology is developed to optimize nonlinear steel frames under several load combinations. For that purpose, inelastic advanced analyses of steel frames are performed using plastic hinge beam–column elements to reduce computational efforts. An improved differential evolution (DE) algorithm is utilized as a global optimizer to refine the solution accuracy and enhance the convergence speed. Compared to the conventional DE algorithm, this newly developed method provides four major improvements such as: (1) a new mutation strategy based on the p-best method; (2) the multi-comparison technique (MCT) to decrease the number of unnecessary objective function evaluations; (3) a promising individual method (PIM) to choose trial individuals; and (4) a trial matrix containing all evaluated individuals to avoid objective function evaluations of duplicate individuals. Furthermore, panel zones are taken account of optimum design for the first time. Doubler plates are designed to prevent panel-zone shear deformations. Three mid- to large-size steel frames considering several load combinations required by AISC-LRFD are considered. Five new and efficient meta-heuristic algorithms are employed for comparison.

Abstract: Publication date: Available online 19 January 2007Source: Advances in Engineering SoftwareAuthor(s): T.T. Tanyimboh, A.B. TemplemanThis article has been removed consistent with Elsevier Policy on Article Withdrawal. The Publisher apologises for any inconvenience this may cause.