This paper introduces a new version of the open-source educational software, LESM (Linear Elements Structure Model), developed in MATLAB for structural analysis of one-dimensional models such as frames, trusses, and grillages. The updated program includes dynamic analysis, which incorporates inertial and damping effects, time-dependent load conditions, and a transient solver with multiple time integration schemes. The software assumes small displacements and linear-elastic material behavior. The paper briefly explains the theoretical basis for these developments and the reorganization of the source code using Object-Oriented Programming (OOP). The updated Graphical User Interface (GUI) allows interactive use of dynamic analysis features and displays new results such as animations, envelope diagrams of internal forces, phase portraits, and the response of degrees-of-freedom in time and frequency domain. The new version was used in a structural dynamics course, and new assignments were elaborated to improve students’ understanding of the subject.
References
[1]
Rangel, R.L. and Martha, L.F. (2019) LESM—An Object-Oriented Matlab Program for Structural Analysis of Linear Element Models. Computer Applications in Engineering Education, 27, 553-571. https://doi.org/10.1002/cae.22097
[2]
Lopes, P.C., Rangel, R.L. and Martha, L.F. (2021) An Interactive User Interface for a Structural Analysis Software Using Computer Graphics Techniques in MATLAB. Computer Applications in Engineering Education, 29, 1505-1525. https://doi.org/10.1002/cae.22406
[3]
Marques, I.R., Lopes, P.C., Rangel, R.L. and Martha, L.F. (2019). Implementação de conexão semirrígida em modelos reticulados no contexto da programação orientada a objetos. Proceedings of the XL Ibero-Latin-American Congress on Computational Methods in Engineering (CILAMCE), Natal, 11-14 November 2019. https://cilamce.com.br/anais/arearestrita/apresentacoes/101/6551.pdf
[4]
Charney, A.F. and Barngrover, B. (2004) NONLIN: Software for Earthquake Engineering Education. In: Blandford, G.E., Ed., Structures 2004: Building on the Past, Securing the Future, American Society of Civil Engineers, Reston, 1-12. https://doi.org/10.1061/40700(2004)177
[5]
Kumar, A., Babu, B.R., and Ramancharla, P.K. (2005) Virtual Structural Dynamics Laboratory. https://www.researchgate.net/profile/Pradeep-Ramancharla-2/publication/265656531_VIRTUAL_STRUCTUAL
_DYNAMICS_LABORATORY/links/54c6f5510cf238bb7d0a1877/VIRTUAL-STRUCTUAL-DYNAMICS-LABORATORY.pdf
[6]
Munipala, A., Pasupuleti, A.D.K. and Ramancharla, P.K. (2012) Structural Dynamics Virtual Laboratory: A Learning Tool Kit for Young Engineers and Practicing Professionals. Proceeding of 15th World Conference on Earthquake Engineering, Lisbon, 24-28 September 2012. https://web2py.iiit.ac.in/research_centres/publications/download/inproceedings.pdf.82d9ca034c80a240.57434545323031325f333230322e706466.pdf
[7]
Gao, Y., Yang, G., Spencer Jr., B.F. and Lee, G.C. (2005) Java-Powered Virtual Laboratories for Earthquake Engineering Education. Computer Applications in Engineering Education, 13, 200-212. https://doi.org/10.1002/cae.20050
[8]
Sim, S.H., Spencer Jr., B.F. and Lee, G.C. (2009) Virtual Laboratory for Experimental Structural Dynamics. Computer Applications in Engineering Education, 17, 80-88. https://doi.org/10.1002/cae.20162
[9]
Panagiotopoulos, C.G. and Manolis, G.D. (2016) A Web-Based Educational Software for Structural Dynamics. Computer Applications in Engineering Education, 24, 599-614. https://doi.org/10.1002/cae.21735
[10]
Katsanos, E.I., Taskari, O.N. and Sextos, A.G. (2014) A Matlab-Based Educational Tool for the Seismic Design of Flexibly Supported RC Buildings. Computer Applications in Engineering Education, 22, 442-451. https://doi.org/10.1002/cae.20568
[11]
Clarke, R.P. (2011) ENGLTHA: An Educational Tool for Earthquake Nonlinear and General Linear Dynamics. Computer Applications in Engineering Education, 19, 97-106. https://doi.org/10.1002/cae.20295
[12]
da Silva, J.G.S, da Silva Vellasco, P.C.G. and de Almeida, N.N. (2002) DINEST: An Educational Software for Structural Dynamic Design and Behavior. Session International Conference on Engineering Education, Manchester, 18-21 August 2002. https://citeseerx.ist.psu.edu/document?repid=rep1&type=pdf&doi=0027ed5efac5807db2cbeac58fd07b47c60b8083
[13]
Brownjohn, J.M.W and Pavic, A. (2002) NDOF: A Matlab Gui for Teaching and Simulating Structural Dynamics. IMACXXVI, Orlando, 4-7 February 2008. https://www.researchgate.net/profile/Aleksandar-Pavic-2/publication/266181526_NDOF_A_MATLAB_Gui_
for_teaching_and_simulating_structural_dynamics/links/550fe8b10cf2752610a178fb/NDOF-A-MATLAB-Gui-for-teaching-and-simulating-structural-dynamics.pdf
[14]
Sonparote, R.S. and Mahajan, S.K. (2018) An Educational Tool to Improve Understanding of Structural Dynamics through Idealization of Physical Structure to Analytical Model. Computer Applications in Engineering Education, 26, 1270-1278. https://doi.org/10.1002/cae.22006
[15]
Mahajan, S.K. and Sonparote, R.S. (2018) Implementation of Comparative Visualization Pedagogy for Structural Dynamics. Computer Applications in Engineering Education, 26, 1894-1902. https://doi.org/10.1002/cae.22024
[16]
Paultre, P., Léger, P. and Proulx, J. (1990) Computer Graphics for Computer Assisted Learning of Structural Analysis. Computers & Structures, 36, 1159-1166. https://doi.org/10.1016/0045-7949(90)90225-Q
[17]
Paultre, P., Léger, P. and Proulx, J. (1991) Computer-Aided Education in Structural Dynamics. Journal of Computing in Civil Engineering, 5, 374-390. https://doi.org/10.1061/(ASCE)0887-3801(1991)5:4(374)
[18]
Paultre, P., Lapointe, E., Carbonneau, C. and Proulx, J. (2016) LAS: A Programming Language and Development Environment for Learning Matrix Structural Analysis. Computer Applications in Engineering Education, 24, 89-100. https://doi.org/10.1002/cae.21675
[19]
François, S., et al. (2021) Stabil: An Educational Matlab Toolbox for Static and Dynamic Structural Analysis. Computer Applications in Engineering Education, 29, 1372-1389. https://doi.org/10.1002/cae.22391
Yuan, X.F. and Teng, J.G. (2002) Interactive Web-Based Package for Computer-Aided Learning of Structural Behavior. Computer Applications in Engineering Education, 10, 121-136. https://doi.org/10.1002/cae.10020
[22]
Barretto, S.F.A., Piazzalunga, R. and Ribeiro, V.G. (2003) A Web-Based 2D Structural Analysis Educational Software. Computer Applications in Engineering Education, 11, 83-92. https://doi.org/10.1002/cae.10040
[23]
Ziemian, R.D. and McGuire, W. (2022) MASTAN2 v.35. http://www.mastan2.com/about.html
[24]
Lopes, P.C., Rangel, R.L., and Martha, L.F. (2020) Ftool 5.0: Nonlinear, Stability and Natural Vibration Analyses. Proceedings of the XLI Ibero-Latin-American Congress on Computational Methods in Engineering, ABMEC/UNILA, Foz do Iguaçú, 16-19 November 2020. http://webserver2.tecgraf.puc-rio.br/~lfm/papers/RangelMartha-CILAMCE2020-Code7805.pdf
[25]
Wilson, E.L. (1979) CAL—A Computer Analysis Language for Teaching Structural Analysis. Computers & Structures, 10, 127-132. https://doi.org/10.1016/0045-7949(79)90079-8
[26]
Turker, H.T., Coskun, H. and Mertayak, C. (2016) Innovative Experimental Model and Simulation Method for Structural Dynamic Concepts. Computer Applications in Engineering Education, 24, 421-427. https://doi.org/10.1002/cae.21720
[27]
Wang, B.P. and Apte, A. (2022) Dyssolve. https://sites.google.com/site/dyssolve/
[28]
Felippa, C.A. (2004) Introduction to Finite Element Methods. University of Colorado, Boulder.
[29]
Bathe, K.J. (2006) Finite Element Procedures. Prentice Hall, Hoboken.
[30]
Booch, G., Rumbaugh, J. and Jacobson, I. (2005) The Unified Modeling Language User Guide. Pearson Education, Upper Saddle River.
[31]
Paz, M. and Kim, Y.H. (2012) Structural Dynamics: Theory and Computation. Springer Science & Business Media, Berlin.