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Pandia Raj Ramar
PhD Research Student
Pandia Raj Ramar is a Research Student of the Cambridge University Engineering Department and affiliated to Jesus College. Raj is in the Structures Group in the Civil, Structural and Environmental Engineering Division. He started his PhD in Structural Engineering in January 2005. He is funded by the Gates Cambridge Trust. He is currently investigating novel forms of Tensegrity Structures with Dr Simon Guest and Prof Sergio Pellegrino.
He graduated from the Government College of Engineering Salem, University of Madras in India with a First Class degree in Civil Engineering in 1999. He had the unique opportunity to contribute to research organizations such as Indian Institute of Technology (IIT) Madras, Research Designs and Standards Organization (RDSO), Indian Railways, and Indian Space Research Organizations (ISRO) for four years on various ongoing projects.
He received his Masters’ of Science by Research (MS) in Structural Engineering at IIT Madras in 2005. He worked with Prof V Kalyanaraman at IIT Madras and associated with the development of a software using Genetic Algorithms (GA) in analysis and design of prestressed concrete and steel truss girder railway bridges for RDSO, Indian Railways. He was also involved in installing this software at RDSO and provided an initial training for its usage. He also had the opportunity to carry out analytical and experimental studies of the buckling behaviour of composite cylindrical shells for ISRO with Prof V Kalyanaraman at IIT Madras. During his Masters’ he also assisted in various design checks that were carried out by structural engineering division of IIT Madras.
Raj is currently investigating novel forms of Tensegrity Structures. Tensegrity structures are an exciting and innovative structural form and they can be made rigid in a particular configuration by a state of prestress or self-stress - when prestressed, any of the members that are in tension can be replaced by a continuous net work of cable, which often allows the compression members of the structure, also known as struts, to be entirely discontinuous from one another. Tensegrity structures are often under-braced and rely on the geometric stiffness to stand: a state of prestress or self-stress is required for their stability in order to stiffen internal mechanisms. In particular, some of the found forms, such as the famous tensegrity needle tower built by Kenneth Snelson, are highly symmetric, consisting of a repeat of a module that itself has high symmetry. We will show that incorporating this symmetry into a structural analysis of these structures gives great insight into the structural mechanics of these structures. The primary objective of the present study is to develop novel forms of tensegrity structures for practical applications especially in structural engineering using the tools of symmetry analysis and group representation theory to structural analysis.
Tensegrity structures can be considered as structures consisting of a continuous network of cables, together with discontinuous struts, that rely on prestress to be stiff and stable - they can be made rigid in a particular configuration by a state of self-stress. Tensegrity towers are a form of tensegrity structure which are compact in two dimensions, but extend in a third direction.
Raj has generated a catalogue of symmetric tensegrity structures using the point group symmetry. The catalogue shows the possible stable tensegrity structures with icosahedral, cubic, or tetrahedral symmetry.
Pandia Raj, R. and Guest, S.D. (2008) "A Tensegrity Catalogue using Point Group Theory", 6th International Conference on Computation of Shell and Spatial Structures, IASS-IACM 2008, Ithaca, New York, USA, May 28-31, 2008.
Pandia Raj, R. and Guest, S.D. (2007) "Form-finding of Repetitive Tensegrity Structures", IASS-2007, Venezia, Italy, December 3-6, 2007.
Pandia Raj, R. and Guest, S.D. (2006) "Using Symmetry for Tensegrity Form-finding", IASS-2006, Beijing, China, October 16-19, 2006.
R. Pandia Raj and V. Kalyanaraman, 2006. “Integrated System for Steel Truss Bridge”, ASCE Structures Congress 2006, May 18-21, 2006, St. Louis, Missouri, USA.
R. Pandia Raj and V. Kalyanaraman, 2005. “GA based Optimal Design of Steel Truss Bridge”, 6th World Congress on Structural and Multidisciplinary Optimization (WCSMO6), Rio de Janeiro, Brazil.
R. Pandia Raj and V. Kalyanaraman, 2005. “Optimization of Steel Truss Girder Railway Bridges using GA and OOM”, International Conference on Structural and Road Transportation Engineering (START 2005), IIT Kharagpur.
R. Pandia Raj and V. Kalyanaraman, 2004. “Object Oriented Implementation of Analysis and Design of Steel Truss Girder Railway Bridges”, Seminar on Recent Trends in Civil Engineering, Institute of Technology, Banaras Hindu University, Varanasi.
V. Kalyanaraman, R. Pandia Raj and Pramod Kumar Parate, 2002. "Experimental study of the behaviour of GFRP stiffened and unstiffened cylindrical shells", proceedings the theme experimental techniques & testing methods, National Seminar on Aerospace Structures, Bangalore.
Pandia Raj, R. and Guest, S.D. (2008) "Tensegrity Catalogue: Part II. Site Symmetry", to be submitted.
Pandia Raj, R. Guest, S.D. and Connelly, R. (2008) "Tensegrity Catalogue: Part I. Point Groups Symmetry", to be submitted.
Pandia Raj, R. and Guest, S.D. (2006) "Using Symmetry for Tensegrity Formfinding", Journal of the International Association for Shell and Spatial Structures. 47(3), 245-252. (pdf preprint)