Advanced seismic engineering protects new biocontainment laboratory
Construction of the country’s new high-level biocontainment laboratory in Wallaceville is proceeding at pace with the foundations, some of the steel framework, and, importantly, the vital earthquake protection now in place.
The new $87 million lab, for diagnosing exotic animal and human disease, is being built for the Ministry for Primary Industries (MPI). It will replace the Ministry's existing laboratories at the Upper Hutt site which are nearing the end of their intended lifespan.
Laboratory Project Director Joseph O'Keefe says the facility is New Zealand's only laboratory approved to contain significant diseases, and as such, will be world-standard, meeting international requirements for safe containment.
"It will contain complex systems and technology to ensure organisms cannot be released into the environment and a part of this is the ability to withstand a one-in-2500 year earthquake, comforting in light of recent events."
Dr O'Keefe says the new building sits on base isolators which can handle relative movement between the ground and building of up to 900mm in any direction.
"During significant seismic shaking, the isolators will significantly reduce the accelerations felt within the building. This, combined with a very stiff superstructure, will have the effect of minimising bending and stretching of the building structure which is a key feature when you need to prevent any breaks in the walls that could breach the containment barrier and stop the lab working."
The lab is designed to remain operational even in an event large enough to render many conventional structures unsafe to occupy. Even damage to utilities will not stop the lab working as it will have its own generator, effluent treatment plant and water storage tanks.
"Acting with the base isolators, the four corners of the new lab are held down by "anchor piles" which penetrate 13 metres into the ground below the basement. The bottom half of each pile is made up of reinforced concrete cast into the tough alluvial gravels below. The top half is hollow, with double-layer steel casing. Inside the casings is a tensioned cable which secures the pile base to the underside of the building while allowing for the 900mm movement. It's not going anywhere," Dr O'Keefe says.
The site was unaffected by November’s 7.8 magnitude Kaikōura earthquake.
"It was, however, a good reminder for the team working on the build of the impacts earthquakes can have, and the reason we spent the first year of construction establishing the very sound foundations that the lab will sit on. We know the building performed exactly as it should have done at this stage of construction, with the ground accelerations experienced."
The exterior of the building is expected to be finished this year, with it set to be weathertight in October/November. Then the complex interior fit-out begins with the installation of building systems designed by international experts. Complete construction is due to finish in mid-2018. After that there is a robust testing and certification process to be completed before it can open for business in early 2019.