Comments on Structural Reliability for Design and Construction as Per Eurocode

Abstract

The replacement of the British standards by the Eurocode, and the Malaysian decision to adopt this change has raised some concerns with regards to the effects it may have on design and construction. Among these effects are the aspects of the structural reliability management introduced in EN 1990 and the respective Malaysian National Annex. In this respect the code introduced measures and procedures to enable engineers to assess the probability of failure of a particular structure and to estimate the partial factors for actions and materials. As such it will be mandatory for engineers, designing in accordance with Eurocodes, to follow the recommendations stipulated in these codes. Furthermore the code introduces specific measures, depending on the class of the building, to be considered for quality management. This will minimize human errors and enhance safety and quality of the structure. Applying all these measures should produce structures with high level of safety, durability and economy. The objectives of the paper are to study the aspects related to structural reliability with respect to probability of failure and quality management measures proposed by the Eurocode. It is also intended to highlight the limitations of the procedure and values given in the code. Accordingly comments have been given on the validity of the partial factors introduced in the code, and new values of probability of failure for reference periods 25, 75 and 100 years have been calculated. Furthermore the procedure to calculate the reliability index β illustrated. It is concluded that in order to produce durable structure with reasonable level of probability of failure, and considering economical aspects, all requirements of the Eurocode must be considered. In addition, Engineers should asses carefully the class of building to be designed and to estimate the probability of failure for that particular building. This should be carried out in agreement with the client. It is proposed that steps towards building a national reliability model, takes into consideration local conditions, should be considered. It is also hoped that this study will open up further investigation and research in this area.