Consideration of reliability and sustainability in mechanical and civil engineering design to reduce oversizing without risking disasters

¹ Institute of Machine Components IMA, University of Stuttgart, Stuttgart, Germany
² Institute for Acoustics and Building Physics IABP, Life Cycle Engineering GaBi, University of Stuttgart, Stuttgart, Germany
³ Fraunhofer Institute for Building Physics IBP, Life Cycle Engineering GaBi, Stuttgart, Germany

^* Corresponding author: dazer@ima.uni-stuttgart.de

Abstract

Technical systems have to be designed that the requirements regarding service life are met with high reliability to ensure safe product operation. In many cases, the design is still based on single events, such as extreme load levels and additional safety factors, in order to ensure reliability, which is accompanied by a high degree of oversizing. This means that significantly more resources are consumed than actually needed in order to ensure the reliability requirement. To prevent reliability from being ensured solely by oversizing, reliability criteria must be supplemented by the claim for sustainability starting with the product design. On the one hand, profound reliability considerations make safety factors obsolete. On the other hand, oversizing is limited by the claim for sustainability. The overall result is a sustainable design while ensuring reliability at the same time. Within this work, two case studies from two different industrial sectors are introduced to show the trade-off in which the design has to be developed and how an overall solution proposal can look like. In both case studies, the savings in terms of resources and greenhouse gases emitted are shown while considering reliability and sustainability during the product design phase.