Civil Engineering March 2021 | Vol 29 No 2

Civil Engineering March 2021 5 Sec t i on Header product with a track record of almost 40 years across five continents. The high level of international recogni- tion and success inevitably attracts copycats, however genuine TRM products are easily distinguished from their inferior copies which are produced with negligible care and attention to safety or quality controls.  #RespectIntellectualProperty  PROVEN DURABILITY The durability characteristics of ductile iron – which is used globally for water pipes – are well known. Recently, the City of Hayward in California, USA, replaced an aging AC transmission main, estimated to be well over a century old, with a new 750 mm diameter ductile iron line. The City of Hayward was unequivocal that ductile iron pipe was their material of choice, due to the strength and durability of the mate- rial, the relative ease in which the shock- resistant material could be assembled, and the long-term resiliency the ductile iron will provide, even in an earthquake prone area. In 2012 the American Water Works Association reported that, based on a nationwide analysis of water pipes across the USA, which took into account the Associations’ test results, field inspections and in-service operations spanning over 50 years, ductile iron pipes in benign soil had generally achieved a service life of over 100 years, and in some cases over 110 years. More than 600 water utilities in the USA and Canada have been using un-coated cast iron pipe material that has provided service successfully for 100 years or longer, and 23 water utilities for more than 150 years. Founded in 1915, the Ductile Iron Pipe Research Association (DIPRA), has provided accurate, reliable, and essential engineering information about cast iron, and now ductile iron, pipe to a wide va- riety of utilities and consulting engineers for more than 100 years. Showcasing the amazing potential of cast iron, DIPRA boasts a Century Club and Sesquicentennial Club, recognising water utilities with cast iron mains that have provided service for 100 years or more, and 150 years or more respectively. This tremendous level of available re- search on the corrosion resistance of ductile iron material shows how, when required, TRM piles can be designed and guaranteed for 100 years of structural service life. Design is performed in accordance with European design codes which enable the design engineer to choose the service life according to the specific project requirements and relevant level of soil and environmental corrosivity. In accordance with the design code, the service life and corrosion level are selected and the appli- cable loss of thickness through corrosion is incorporated into the design process. TRANSPARENT ON-SITE DESIGN VERIFICATION The in-situ soil conditions are verified during TRM pile driving, which is when the TRM site team like to say that every pile “talks” to them and helps them understand what is happening beneath the ground. Design and installation of TRM piles into saturated or unstable soil profiles (e.g. sand with or without groundwater at or near the surface) has no impact on overall piling cost and installation time, even when such challenging sub-surface condi- tions are encountered unexpectedly. All these factors enable the TRM piling system to enjoy the unique benefit of being backed by both a €10 million product DIPRA’s Century Club and Sesquicentennial Club recognise the long lifespans of cast iron pipes (courtesy DIPRA, USA) The TRM piling system illustrates many benefits at remote locations, including minimised concrete volume TRM friction piling shoe compacts and improves soil by forming a full displacement pile up to 320 mm diameter