Nelson Airport - A seismic success
A new Nelson Airport became necessary to cater to the increasing number of passengers who pass through the sunny region. Additionally, the reality of New Zealand’s unpredictable seismic activity meant that, after analysis, the existing 1970’s airport fell below current Building Code requirements.
The vision was for the project to resonate strongly with the Nelson environment, reflecting the surrounding hills and landscape.The new airport had to be logical, functional and flexible to enable growth in the future. The design accommodates use by six airlines, six rental car operators, three food and beverage outlets, a retail outlet, a number of stakeholders, as well as the multitude of passengers. The project’s success, therefore, relied heavily on operational performance and design quality.
It was essential for the architects to understand the requirements of the users and to be able to communicate them in the developing design.
The use of Virtual Reality (VR) enhanced this communication and allowed viewers to fully engage with the environment of the project. The use of VR has given a far greater depth of instant understanding than traditional presentation methods. This was particularly helpful for familiarisation and training for Nelson Airport Limited (NAL), as well as the resolution of signage and advertisement placement - all of which contribute to the final operational performance.
The primary innovation of the project is the distinctive roof triangle components and sub-assemblies. The triangles were assembled out of prefabricated LVL rafters, a perforated acoustic plywood diaphragm, posi-strut beams with acoustic insulation, and the roof membrane.
The LVL was chosen for its load bearing strength and flexibility in seismic and wind movements. The use of LVL in the highly innovative roof form allowed for large structural spans with minimal internal columns.
CONSTRUCTION AND ASSEMBLY
The Computer Numerically Controlled (CNC) cut LVL components were trucked to site from the nearby Nelson Pine Industries factory. The components were assembled into triangular sub-assemblies in a hangar on the airport grounds. This space could accommodate the construction of four triangles (approximately 19m by 7.5m each) at one time.
The construction of the roof panels at ground level ensured a safe working platform and allowed for consistency and efficient construction of the 56 triangles. Working within a controlled environment meant work could continue in all weather conditions which has a programme advantage.
Each pre-assembled roof triangle was locked at each corner into the LVL columns and fitted with structurally designed Resiliant Slip Friction Joint’s (RSFJ). The RSFJ is an innovative seismic design that has been specified to fit seamlessly into the LVL columns. The joints consist of two outer plates and two centre slotted plates that are clamped together with high strength bolts and disc springs. During an earthquake the center slotted plates slide against the outer plates. The friction in this movement releases energy and allows the structure to absorb the seismic force (see image / diagram).
Prefabricated construction enabled the terminal building to be erected and enclosed rapidly. The methodology has had a positive impact for Health and Safety on-site and it has also enabled increased control of Foreign Object Debris (FOD) - a critical hazard at airports.
The main site challenge was to keep the terminal and car park operational during the construction. The project was therefore split into distinct stages to ensure a smooth transfer between the use of the old and the new airport. During Stage A of the terminal construction, businesses continued as usual within the existing building. Once Stage A was complete, businesses transferred quickly into the newly constructed spaces to enable demolition of the old structure. At the time of writing, construction of Stage B was underway to complete the remaining 40% of the terminal project .
The project has received a hugely positive response from passengers, locals and users alike. A recent Nelson Mail / Stuff article quoted visitors reactions with comments such as, ‘very Nelson’, ‘spacious, modern’, and ‘absolutely stunning’.
Prefab materials used: Laminated Veneer Lumber (LVL) Rafters by Nelson Pine Industries (PrefabNZ Member), Posi-Strut Beams by MiTek New Zealand Ltd (PrefabNZ Member), Acoustic Insulation, Plywood Diaphragm, Roof Membrane
||Nelson Airport Ltd|
Naylor Love / Gibbons / Fulton Hogan
Studio Pacific Architecture (PrefabNZ Member)
Dunning Thornton Consultants (PrefabNZ Member)
|Prefab Type:||Component / Panel|