Assessing riveted connections to Eurocode 3

Abstract

2The focus of this paper is the assessment of wrought iron and early steel riveted connections in the future, with recommendations as to how different codes currently deal with the assessment and what may change if alternative codes are adopted. As British standards are being replaced by Eurocodes for design, it is inevitable that assessment codes of practice based on British standards will be replaced by those based on Eurocodes. This progression will ensure that future structures are designed and assessed using codes based on similar philosophies. However, this will also lead to older structures designed according to older codes based on different philosophies and constructed of materials not covered by the Eurocodes also being assessed according to Eurocode-based assessment codes. A similar situation already exists with structures being assessed using British standard-based assessment codes, which were written for the design of steel structures. This has resulted in the leading asset-owning organisations, such as Network Rail and Highways England, including guidance on adapting calculations to account for different material types.1. Introduction The history of riveted connectionsConnections are only as strong as their parent material, and therefore both the physical connection (such as a bolt or rivet) and the members they are connecting should be considered when assessing the strength of a connection.Rivets are permanent mechanical fasteners predominantly found on wrought iron and early steel structures. A rivet consists of a smooth cylindrical shaft with a 'head' at one end, with the opposite end known as the 'tail end'. Historical rivets were placed in a punched or drilled hole through two or more plates and the tail was deformed to create another head, sandwiching the plates together.At the peak of their use in the nineteenth and early twentieth centuries, fabricating riveted structures was very labour intensive, with the rivets being hammered into position manually. It is understood that riveting was generally undertaken in the fabrication shop as opposed to on-site. Figure 1 shows typical rivet design data, given in Molesworth's Pocket Book of Engineering Formulae (Molesworth, 1862).The use of riveted connections rose and fell correspondingly with the rise and fall in favour of wrought iron, approximately between 1830 and 1890, but persisted as a favoured form of connection as early steel replaced wrought iron. Riveted connections appeared in all areas of fabrication, from shipbuilding to bridges, anywhere two or more plates required connecting, until they were slowly phased out by bolted connections, which required less physical effort to install and were less likely to damage the structure during installation or removal.It is important to understand the difference between riveted and bolted connections. When a rivet was driven into position, it expanded to fill the hole completely and therefore removed the potential for slip, in contrast to modern bolted connections, which are provided with a 2 or 3 m...