Zbornik Radova Građevinskog Fakulteta (Jan 2015)
About modelling and designing concrete structures according to durability
Abstract
Almost to the end of the twentieth century durability was treated implicitly and its service life (SL) was not defined in technical regulations (codes) for the design of concrete structures (CS) which have been applied. Over time this approach has proved to be insufficient, especially in intensive growth environment pollution. In the current codes for the design of CS (e.g. EN, i.e. Eurocode - EC), durability is treated implicitly and most do not contain quantified guidance for the design of CS SL longer than 50 years. The SL is implicitly defined with no clear meaning, what is the end SL? It was considered that application of the provisions of these codes result in permanent CS service, and that they will achieve the required SL, which is often not the case. Experiences show that this approach fails to meet the requirements of durability, especially when the requested SL is significantly longer than 50 years (100 or more). Modern approach to the design of reliable CS is based on performance and behaviour during SL. Probabilistic approach (based on probability and reliability) design enables a more accurate forecast of the behaviour of CS during SL, but it is complex and the possibility of its wider practical application is in the developmental stage. Based on a review of literature and contemporary codes, the paper analyzed some models and approaches to the design of CS, according to durability. The emphasis is on the design of the performance, based on the indicators of durability of concrete, with current proposals for a revision of EN 1992 and EN 206, based on the experience gained and the latest research in this field.
