Strengthening and refurbishment of Severn Crossing, part 4: TRRL research on Severn Crossing

The Transport and Road Research Laboratory (TRRL) has been involved in research into aspects of the behaviour of the Severn Crossing since 1963, some three years before the structure was opened to traffic. Early work, concerned with the performance of surfacings, traffic loadings and traffic induced stresses, led to the prediction that fatigue cracking would occur in welded connections in the steel deck. Much of the experimental effort was therefore directed to fatigue testing and stress measurement. This paper also describes TRRL research on the performance of the cables, corrosion of the steelwork, temperature effects, wind effects, and specific work on the profilometry of the decks, stiffness of the diaphragms, movement at shear key bearings, inspection of the deck welds and properties of de-icing materials. The paper provides an overview of TRRL's involvement. (A)