Michael Hung Yau-yan wants the legacy of his career in engineering to be two cheap, simple and reliable devices he claims will remove the threat of potentially catastrophic building collapses. But the problem, he says, is that the government and property developers are unlikely to even look at his new crystal sensor and shearography technologies until the city is faced with such a disaster. 'If we don't do something, there is a high risk that this will happen, because buildings have a lifetime, just like us,' the soon-to-retire City University engineering professor said yesterday. 'It is not in the interest of a building's owners to have people know about problems with their building. So we need government help, but governments only respond to a crisis, rather than have the vision to look forward.' Professor Hung said the city has 50,000 buildings exceeding 100 metres, all of which are susceptible to collapse from the rigours of age, vicious typhoons and natural damage to their foundations. Hong Kong's geography, with buildings erected on steep slopes and land reclaimed from the sea, meant the foundations of buildings faced additional pressure. The only way to test whether the foundations are secure is to conduct 'primitive' building surface checks - including tapping a wall with a hammer - or taking concrete samples from the structure. Professor Hung said his technologies remained simple and inexpensive but were more reliable and removed the problem of human error. The crystal sensor can be installed when a building is being built or inserted simply using a drill. Stresses in the building's foundations are detected because the crystal changes colour. Shearography, a laser imaging technique, expands on a well-known engineering theory and allows for tests to evaluate external walls. It takes only two minutes to analyse an area of two square metres. He said his technology was potentially worth millions if patented. 'But I don't want money, I have enough money,' he said. 'I would like this to be available to benefit mankind everywhere.'
