Technical Guidance Note (Level 1, No. 25): Introduction to fatigue

The subject of this guidance note is the design of reinforced concrete beams to BS EN 1992-1-1 – Eurocode 2: Design of Concrete Structures – Part 1-1: General Rules for Buildings. It covers the design of multispan beams that have both ‘L’ and ‘T’ cross section profiles. (This article was updated in October 2016 to reflect errata issued since its original publication.)

Imposed load is defined as the load that is applied to the structure that is not permanent and can be variable. In Eurocode phraseology, it is described as a 'quasi-permanent variable action'. Please be aware that this note does not cover lateral loads onto barriers, balustrades and axle loads from vehicles. These will be covered in a forthcoming note. (This article was updated in October 2016 to reflect errata issued since its original publication.)

This Technical Guidance Note concerns lateral loads that are applied to barriers and wheel axle loads from vehicles. Barrier loading is dealt with slightly differently to other forms of imposed loading. The nature of the loading can vary from people leaning against barriers to vehicles colliding with them at speed. Axle loading from vehicles has to be treated somewhat differently to other forms of imposed loading. While it is possible to assume a blanket area load to represent them, it is the point load from each wheel that needs closer attention.