The beam elements and their engineering applications

Daigoro Isobe

University of Tsukuba

In this lecture, unique techniques applied to linear Timoshenko and Bernoulli-Euler beam elements, and their applications in various engineering fields are presented.

First, a brief outline of the Adaptively Shifted Integration (ASI)-Gauss code incorporated with linear Timoshenko beam elements and their applications are introduced. This code provides higher computational efficiency than the conventional code by the shifting numerical integration points of beam elements to appropriate positions according to the elasto-plastic properties. It can be applied to those problems with strong nonlinearities including phenomena such as member fracture and elemental contact. Several examples such as aircraft impact analysis of the WTC tower, seismic pounding analysis of the Nuevo Leon buildings, collapse analysis of a building subjected under tsunami wave and debris collision, and motion behaviour analyses of indoor non-structural components such as ceilings and furniture are presented.

Next, the parallel solution scheme of inverse dynamics using Bernoulli-Euler beam elements and its application to a torque cancelling system (TCS) are introduced. The TCS calculates reaction moments generated by motors in robots by considering the dynamics of the numerically modelled system. The developed scheme can handle different types of configurations and can also consider elasticity of constituted links or passive joints by only changing the input numerical model. Once the reaction moment is known, it can be cancelled by applying an anti-torque to a torque generating device. Some applications of the system are presented in this lecture.

Biography:

Professor Daigoro Isobe received his Ph.D. degree from the University of Tokyo in 1994, and is currently a professor at University of Tsukuba, Japan. He has conducted various researches on collapse behaviors of building structures, and has also introduced unique approaches in the field of robotics using the essence of computational mechanics. He has published over 400 journal papers, conference papers, book chapters, and books. He served as a chairman of several international conferences and workshops such as COMPSAFE 2020, a special interest conference of IACM, and IWACOM-III, a unique set of international workshops held under JSCES. He received the Ichimura Award upon those achievements in the field of structural collapse simulations, in 2014, in presence of Princess Akiko of Japan. He also received the Kawai Medal from JSCES in 2015, and the Computational Mechanics Achievements Award from JSME in 2019. He is now a fellow of JSME and the President of JSCES.