Beneath the Surface

Awarded $2.54m over 4 years to research the seismic response of underground services

WSP Opus Research was successful in the Ministry of Business, Innovation and Employment’s recent science investment round.

The saying goes that while a duck seems to be moving serenely across the pond, its feet are actually paddling like mad. Our cities are the same – while we go about our daily lives, below us a vast infrastructure is keeping the cities running.

Similarly, after the shaking stopped in Christchurch it was easy to see the damage the earthquakes had wrought on the city above. What wasn’t as evident was what effect they had underground and this is what this new research project led by Dr Rosslyn McLachlan focuses on.

WSP Opus will be working closely with industry to research lessons from the damage caused to underground services such as water supply, wastewater, storm water and telecommunications in order to make those services more resilient to future seismic events.

A GIS database of damage data from Christchurch will be combined with state-of-the-art 3D geological information and those findings will be further analysed using a large shaking table with earthquake loading sequences in order to look at and optimise the behaviour of typical models of pipeline components. To ensure this process is robust, 3D numerical analysis will also be used to assess various scenarios.

The project will also draw on GNS Science’s expertise around geology and earthquake load sequencing, as well as their RiskScape model, which provides a framework for calculating the impact risk from different types of natural hazards. The knowledge gained from the testing and analysis will then enhance the RiskScape model.

When combined with WSP Opus’ previous work, this physical and numerical analysis will help in developing methodologies to assess the remaining life of existing underground utilities. This will allow more informed planning and decision-making around the positioning of utilities within the Christchurch area, as well as provide the basis for enhanced asset management methodologies applicable throughout New Zealand.