Griffith puts timber buildings to the test

Griffith University researchers are putting timber to the test to see if tall wooden buildings are the way forward for our cities.  

For the first time in the world, the behaviour of mass timber buildings to resist the loss of a main structural element has been investigated using hi-tech laboratory equipment at the Gold Coast campus.  

The demonstration was observed by representatives from the Queensland Government, Arup, Lendlease, and will lead to a better understanding of the behaviour of timber buildings and eventually inform the improvement of current design rules and yield safer buildings.  

Associate Professor Benoit Gilbert from Griffith’s School of Engineering and Built Environment is part of the team testing engineered solid wood products, such as Laminated Veneer Lumber (LVL), Glue laminated timber (Glulam) and Cross Laminated Timber (CLT) and their capabilities in collapse resistance.  

Reaching timber building heights of five to six storeys has been made possible thanks to products such as these. Australian examples of mid-rise timber buildings include International House Sydney at Barangaroo and the world’s tallest mass timber office building on King St in Brisbane, which has just been commissioned.  

Associate Professor Gilbert said recent changes in legislation has prompted the rise in popularity for mid-rise buildings internationally.  

“Timber has many functional, aesthetic and environmental benefits: it’s a renewable, durable and environmentally sustainable building material,” Associate Professor Gilbert said.  

“Using timber in building constructions enables less resources and less energy to be consumed when compared to traditional steel and concrete buildings, and the buildings require less time to be constructed as they are erected from prefabricated elements.  

“Griffith University has a well-equipped structural laboratory where full-scale tests of timber elements are being performed and the structural behaviour of mass timber buildings under large deformations is investigated.”  

A three-year collaborative project investigating the prospect of even taller timber buildings – or mass timber buildings) has been recently funded between Griffith, the Department of Agriculture and Fisheries, the Queensland Government, Arup and Lendlease.  

The project will examine the progressive collapse behaviour of mass timber buildings with CLT floors.  

Lendlease Senior Structural Engineer Richard Neuhercz said testing robustness was very important with multi-story buildings, especially when part of a structure was compromised to determine if the rest of the structure will remain stable.  

“Testing will help illustrate the way this works – we can learn a lot from these tests, which will help inform and support decisions,” Neuhercz said.  

Toby Hodsdon, and Associate with Arup Queensland, said seeing a full scale robustness test like Griffith Engineering’s will give a valuable insight into how mass timber structures behave.  

“In the event of an accident like a blast, impact from a moving vehicle or a fire, it gives an insight into what happens when a column in the structure is removed,” Hodsdon said.  

Xlam Design Manager and Structural Engineer Jeremy Church said testing a specific connection or joint was common, but a larger scale test of system has not been seen.  

“I think it will be the catalyst around designing progressive collapse theories,” Church said.  

The Griffith team of engineers comprises Assoc Prof Benoit Gilbert, Prof Hong Guan, Dr Gunalan Shanmuganathan, Dr Hassan Karampour, Dr Ian Underhill and PhD students Mr Chunhao (Alan) Lyu, Mr Mahyar Masaeli and Ms Xinyi (Chelsea) Cheng.