Calibration of structural design standards for sustainable development
Prof. Jochen Köhler
To date our built environment is broadly developed and maintained on the basis of structural design standards. Most design standards contain simplified semi-probabilistic safety concepts that help daily structural engineering decision making using simple calculus. For few projects the semi-probabilistic safety concept is replaced by advanced probabilistic methods that allow for reliability based design. Neither include explicit consideration of optimality criteria. However, for the development and the calibration of the semi-probabilistic and probabilistic safety concepts it is important that societal preferences in regard to risk acceptance and the optimal use of natural resources are explicitly considered.
In the present contribution, the development and calibration of semi-probabilistic and probabilistic structural design standards is represented as a formal decision problem allowing an optimal combination of reliability elements to be identified.
It is first focused on the risk based calibration of a reliability based design codes and a rational basis for the development of reliability criteria is presented. Thereafter the calibration of semi-probabilistic safety concepts is considered and the huge resource saving potential is discussed. In this part of the lecture, the recent insights of the ongoing revision of the Eurocodes are presented.
The lecture is closing with some outlook on future developments and necessary paradigm shifts for codified structural design.
Jochen Köhler is a Professor at the Department of Structural Engineering, Faculty of Engineering, at the Norwegian University of Science and Technology (NTNU), Norway. He obtained his PhD degree in Engineering Sciences in 2006 from ETH Zurich, Switzerland. His research areas and interests focus on structural reliability, risk based decision making, code calibration, probabilistic material and load modeling with special topics in traffic and offshore engineering. He participates in various national and international research networks: fib (The International Federation for Structural Concrete), EERA (European Energy Research Alliance), COST Action TU 1406, IABSE (The International Association for Bridge and Structural Engineering), etc. Since 2023 he is the president of the Joint Committee on Structural Safety (JCSS).