Australia's east coast braced on Wednesday for a tropical cyclone that is swirling towards Brisbane, the country's third-most populous city, as authorities warned thousands of properties were at risk due to strong winds and flash flooding.

Chaos has erupted at some sandbagging sites as Queenslanders bunker down ahead of Tropical Cyclone Alfred smashing into the coast.

The stadium gig on the Gold Coast slated for Wednesday night (March 5) was the last stop on the Down Under run of the veteran group's "Saviors" tour.