Robustness and Eurocodes

The topic of robustness is essentially covered by two Eurocodes, EN 1990: Euro-code: Basis of Structural Design [5] which provides the high level principles for achieving robustness and EN 1991-1-7 Eurocode 1: Part 1-7 Accidental Actions [6] which provides strategies and methods to obtain robustness and the actions to consider

EN1990: Unravelling expressions 6.10 and 6.10a/6.10b

In EN1990, in persistent and transient design situations, action effects should be derived according to three different sets of combinations of actions: expressions 6.10 or, alternatively, the most adverse between expressions 6.10a and 6.10b or the most adverse between expressions 6.10a modified and 6.10b, being the choice among the three different sets left to the National annex. As the three formulations are not equivalent in terms of structural reliability, the reliability indexes associated which each of them in some simple, but very clear, case studies, have been determined, highlighting the differences and their significance. For each case, and for various ratios between the variable and permanent loads, the resistance of the considered structural member has been set equal to the capacity required by each set of combination of actions considered and the reliability indexes have been determined considering real load combination fitted in turn by one if the alternative sets of expressions, in such a way that the comparison focuses only on the reliability variations induced by combination rules. Results show that the target reliability level indicated in EN 1990 is commonly reached using expression 6.10, while expressions 6.10 a and 6.10b can lead to lower values, especially when the bias of resistance’s distribution is small, the C.O.V. of the resistance is high and the real distribution is fitted by [6.10]. In the authors’ opinion expressions 6.10 a modified and 6.10 b are not to be adopted, leading in some cases to significant reduction of the reliability indexes

Reliability differentiation in ULS checks according to EN1990

In EN1990, action effects in persistent and transient design situations are to be derived according to appropriate combinations of actions. Three different sets can be chosen alternatively in the National annex: expression 6.10 or the most adverse between expressions 6.10a and 6.10b or the most adverse between expressions 6.10a modified and 6.10b. Since the three formulations are not equivalent in terms of structural reliability, a specific study has been performed to compare the reliability level associated with each of them, in some simple but very clear case studies. Results show that the target reliability level required in EN 1990 for ULS checks is commonly reached using expression 6.10, while expressions 6.10 a and 6.10b can lead to lower values, especially when the C.O.V. of the resistance is high

Designer's guide to Eurocode 1: actions on buildings EN1991-1-1 and -1-3 to -1-7

This series of Designers Guides to the Eurocodes provides comprehensive guidance in the form of design aids, indications for the most convenient design procedures and worked examples. The books also include background information to aid the designer in understanding the reasoning behind and the objectives of the codes. All of the individual guides work in conjunction with the Designers' Guide to EN 1990 Eurocode: Basis of Structural Design. The part of Eurocode 1 covered by this guide, EN 1991-1, addresses the general actions on building and civil engineering structures. This Designers' Guide looks specifically at actions on buildings, including full explanation, commentary, examples, and direction to the National Annex documents on each of the following sub-parts of the code: 1-1: Densities, self-weight and imposed loads 1-3: Snow loads 1-4: Wind actions 1-5: Thermal actions 1-6: Actions during execution 1-7: Accidental actions This guide is essential reading for: civil and structural engineers code-drafting committees clients structural-design students public authorities product manufacturers in fact, everyone who will be affected by the Eurocodes

Structural eurocodes Their adoption in the UK

SIGLEAvailable from British Library Document Supply Centre-DSC:2277.485(3/99) / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Designers' guide to Eurocode : basis of structural design, EN 1990 / H. Gulvanessian, J.-A. Calgaro, M. Holický.

Prev. ed.: 2002.Includes bibliographical references and index.Book fair 2013.ix, 190 p.

Eurocode 1 The code for structural loading, thermal actions, actions during execution, accidental actions, traffic loads on bridges, actions in silos and tanks, and actions induced by cranes and machinery

Part 2 of 2Available from British Library Document Supply Centre-DSC:2277.485(13/98 pt.2) / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo

Eurocode 1 The code for structural loading; basis of design, dead, imposed, fire, snow and wind loads

Part 1 of 2Available from British Library Document Supply Centre-DSC:2277.485(13/98 pt.1) / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo