prEN 1991-1-4:2021: the draft Second Generation Eurocode on wind actions on structures - a personal view

This paper traces the drafting of the new EN 1991-1-4 Eurocode 1 – Actions on structures - Part 1-4: General actions - Wind actions within Mandate M/515 of the European Commission to CEN, for the evolution of structural Eurocodes towards their Second Generation. Work of the Project Team started in August 2017 and ended in April 2020, with delivery of a final draft for public enquiry. The revised document contains several modifications with respect to the existing 2005 version, and new sections were added, covering aspect not dealt with in the previous version. It has a renovated structure, with a main text limited in size and containing only fundamental material; all the remaining information, either normative or informative is arranged into thirteen annexes. Common to other Eurocode Parts, general requests from CEN were those of reducing the number of Nationally Determined Parameters and of enhancing the ease of use. More specific requests were those of (a) drafting of a European design wind map, (b) improving wind models, (c) reviewing force and pressure coefficients, (d) reviewing the procedures for the evaluation of the dynamic response, as well as (e) making editorial improvements aimed at a more user friendly document. The author had the privilege to serve as Project Team member for the drafting of the new document, and this paper also brings his personal view concerning some general aspects of wind code writing, and some more specific aspects about the particular document.