Prof. Dr. Peter Jan Pahl
Technische Universität Berlin
Peter Jan Pahl is Professor Emeritus at the Technische Universität Berlin and has held the Chair for Theoretical Methods in Civil Engineering from 1969 to 2005. He graduated as B.Eng. from the Stellenbosch University in 1960 and in 1964 was awarded the Sc.D. degree by the Massachusetts Institute of Technology, where he served as Assistant and Associate Professor until 1969.
Professor Pahl led the development of Bauinformatik in Germany, and thus contributed to the modern digital approach in engineering. He is a past president of the International Society on Computing in Civil and Building Engineering. His international activities over four decades include co-operations with universities in China, India, Iran, Russia, Turkey, South Africa and the United States of America. Peter Jan Pahl holds honorary doctorates from universities in South Africa (Stellenbosch), Germany (Weimar) and Russia (MISI).
Nonlinearity in Structural Engineering
Engineers favor linear systems, whose output is proportional to their input. This attitude contrasts with nature, where most systems are nonlinear. The consequence of the discrepancy between engineering attitude and physical reality is that engineering education favors linear theories, whereas many of the phenomena which limit the serviceability and safety of engineering products result from nonlinear behavior. Because linear behavior is so much simpler to formulate than nonlinear behavior, and because linear solutions are so much simpler to determine than nonlinear solutions, concentration on linearity seems to contribute to efficient education. The question is, however, whether engineers are prepared adequately through their studies to deal with problems that nonlinearity in nature inevitably poses, and with which they must deal as part of their responsibilities in engineering practice.
Structural engineering is a discipline where traditional education emphasizes linear models, whereas serious problems in practice are the consequence of nonlinearity. Leonard Euler illuminated this point in 1757, when he discovered the buckling of columns under axial load, which has been the cause of dramatic failures of structures. Some of the main differences in the theories and methods for the linear and nonlinear analysis of space frames and space trusses, and the research and teaching suited for the nonlinear phenomena, are presented in the lecture. The topics covered include load paths, incremental solutions, singular points and load path continuation.
Prof. Dr. Vera V. Galishnikova
Peoples’ Friendship University of Russia (RUDN University)
Prof. Vera V. Galishnikova is the Head of the Department of Civil Engineering of the RUDN University. She serves as an Academician since 1991. In the past Dr. Galishnikova served in Saratov State Polytechnic Institute (Saratov, Russia), Volgograd State University of Architecture & Civil Engineering (Volgograd, Russia) and Michigan State University (Michigan, USA).
Prof. Vera Galishnikova took her engineering education in Saratov State Polytechnic Institute (Saratov, Russia), and specialized in Civil Engineering. She received her first PhD degree from the Moscow Institute of Civil Engineering in 1991, and in 2004 second PhD degree from the Michigan State University. Prof. Galishnikova received her DSc degree from the Supreme Attestation Commission of Russian Federation in 2016.
Computational Civil Engineering; Building information modeling; Topological computer models of buildings; Computational geometry; Computational mechanics of complex steel structural systems – latticed plates and shells, thin-walled plate and plate-rod structures; Nonlinear finite element analysis of space frames; Nonlinear stability of structures; Structural renovation and complex modernization of buildings etc. are the main fields of her research.
Prof. Vera Galishnikova is author of more than 50 research papers published in peer reviewed international journals, more than 15 research papers published in international conference proceedings and 2 monographs etc. She is member of some professional and academic societies, such as American Society of Civil Engineers, Phi Beta Delta Honor Society for International Scholars (USA) etc.
Operative Models in Science and Engineering
Models play a central role in science and engineering. A model is an abstraction of those properties of an original which are essential for a particular task. Scientists and engineers base their theories, decisions and actions on models. The transition from static to operational models is one of the fundamental changes that are presently occurring in science and engineering.
Traditional models consist of calculations, reports and technical drawings on paper. These models are static: their data can only be used and passed on through human intervention. Today, the models themselves use input data to generate information which is required to design, construct and operate originals, and to transfer this information in networks. These models are called operative models.
Two examples will be presented to illustrate the transition from static to operative models and its influence on the practice of our professions: models for the nonlinear behavior of light space trusses and space frames, and models for building information. It will be shown that new theoretical foundations had to be developed for these models, and that the work flow in the professions has been changed by the models.
The introduction of operative models in the professions has revealed a set of features which influence their benefits. It has become evident that beneficial application of operational models depends on the quality of engineering education. These issues will also be addressed.