ISO has published a new standard to help engineers, builders, and regulators to design structures that are safe and resistant to failure due to environmental and mechanical stresses, and to material degradation.
Buildings, civil engineering works, industrial structures, and their components should be conceived, constructed, inspected, maintained and repaired in such a way that, under foreseeable environmental conditions, they maintain their required performance during their design lives with sufficient reliability for the safety and comfort of users and the intended use of the structure.
ISO 13823:2008—General Principles on the Design of Structures for Durability specifies general principles and recommends procedures for the verification of the durability of structures subject to known or foreseeable environmental actions, including mechanical actions, causing material degradation leading to failure of performance. It will help to ensure reliability of performance throughout the service life of the structure.
This International Standard has the following objectives:
- to improve the evaluation and design of structures for durability by the incorporation of building science principles into structural engineering practice, and
- to provide a framework for the development of mathematical models to predict the service life of components of the structure.
Prof. A.M. Brandt, Chair of ISO/TC 98, Bases for Design of Structures, comments, "The general principles in the verification and design of structures and components for durability in this International Standard should be used whenever a minimum service life is required, for new structures as well as for the assessment of existing structures."
The standard is intended to serve a similar harmonization role that ISO 2394:1998, General Principles on Reliability for Structures, has had over the past 30 years for the verification and design of structures against failure due to mechanical stress, ranging from gravity to wind, snow, and earthquake.
The goal is to ensure that all analytical models are incorporated into the limit states method, the same as currently used for the verification and design of structures.
ISO 13823:2008 covers the following topics:
- basic concept for verifying durability,
- durability requirements,
- design life of a structure and its components,
- predicted service life, and
- strategies for durability design.
This International Standard does not directly address sustainability for structures. Most considerations of sustainability, such as the choice of material as it affects waste and energy consumption, are outside its scope. But indirectly, durable structures improve the sustainability of infrastructure.
ISO 13823—General Principles on the Design of Structures for Durability, was developed by ISO technical committee ISO/TC 98, Bases for Design of Structures, Subcommittee SC 2, Reliability of Structures. For more information visit www.iso.org.