Charles was HERA’s structural engineer for nearly 24 years. In this time, he made significant contributions to the New Zealand structural steel industry being responsible for standards, guidelines and research program development. His passion for seismic and fire engineering and composite interaction led to many innovative solutions which are now daily used in the NZ structural steel industry and indeed make it onto the world stage.
When Charles started at HERA, the market share of multi storey steel construction was basically 0% – today it is in the order of over 50%. Dr Clifton’s work was probably the most important single person contribution to this amazing growth of structural steel in New Zealand. Now as Associate Professor in all matters structural steel and composite construction Charles continues to educate and train the next generation of structural engineers in New Zealand ensuring they are aware of the tremendous opportunities a career in structural steel has to offer.
Having a passion for everything seismic and following the Northridge and Kobe earthquakes, which showed that structural steel had also some performance issues, Charles engaged in in-depth research on how to improve earthquake resistance of structural steel-framed building systems. The probably best known outcomes are Charles’s damage tolerant moment resistant connection details, such as the sliding hinge, where following seismic action the connection goes back into its original position. These designs are now standard in New Zealand’s high-rise buildings making them a much safer place to be in an earthquake.
The 9/11, event where the two World Trade Centre Buildings collapsed, caused Charles some sleepless nights and he engaged in a study of this event leading to a publication after only about a week detailing the likely causes of the collapses. This early account of what happened was published around the world. However the most significant evidence of Charles’s knowledge, experience and judgement was the fact that, when after years of intensive investigations the official findings were revealed, Charles only needed to adjust some minor details to update his original report.