On Wednesday, staff walked off the job for the first time in more than a decade after talks broke down between the university and the union over pay, job security and "debilitating" pressure on academics.

Almost 200 staff gathered outside the university refectory just after midday - some of them brand new union members drawn out of their offices and lecture halls by an eleventh hour threat from management now known on campus as #SausageGate.

On Friday, an email from chancellery warned pay might be docked for non-union staff attending a planned strike-day fry-up on their lunch hour.

Going along to the barbecue, even on a break, might  "constitute participation" in the strike, which is unlawful for those outside the union and attracts a "minimum four hour pay reduction", the email read.

While the National Tertiary Education Union rejected the claim as "ridiculous", UC's threat proved to be a powerful recruiting tool.

Within an hour of the email, the union reported a "significant spike" in new memberships.

"It would be a bit extreme if employers had the right to dictate whether or not you can go to a barbecue and have a sausage on your lunchbreak," one employee said.

By Wednesday the university had backed down on the threat, assuring a number of staff they would not pursue action against non-union members at the barbecue.

"In the best interests of our staff, we informed them about the definition of unlawful action so that they are fully informed," a spokeswoman said.

A union spokesman said that, while banned sausages might seem trivial, such "dirty tricks" were symbolic of many things wrong at UC. There was a lot of anger on campus, he said, as pay continued to lag behind the rest of the sector, workloads piled up on the desks of both academic and professional staff and casualisation increased.

A number of classes were cancelled on Wednesday afternoon but a spokeswoman for the university called the disruption minimal and said affected students had been notified.

A second full-day strike is also looming on the horizon if management "don't take staff concerns seriously" at upcoming negotiations on Thursday.

Casual academic Sarah Ambrose said things were getting worse on campus, with jobs vacated by staff during a round of voluntary redundancies earlier in the year remaining empty. Casuals were regularly working beyond their paid hours and some courses were even reducing assignment word count to speed up marking, she said.

On Monday, the university acknowledged staff concerns and encouraged them to raise them with managers "to assist in managing their workload".

"We know that filling vacant positions will assist greatly," the spokeswoman said.

The university had recieved "significant interest" for the 60 academic and 30 professional jobs currently open, she said, and many offers had already been accepted.

But the university has stood by a program it designed to fast-track academic promotions, despite concerns it is exploiting early career researchers.

At least half of academics don't make it through what has become known around campus as the "burn and churn program" or the seven-year probation and a letter signed by about 30 senior professors has called for it to be axed.

Those in the scheme, known as assistant professors, can be fired before the end of their seven-year contract if they are deemed unlikely to achieve the ranks of associate professor, meaning talented lecturers are often lost to their faculties.

Dozens of former and current academics at the university have told The Canberra Times of the scheme's destructive toll on their health, saying they felt pressured to pump out research to survive.

One academic on sick leave described the scheme as unrealistic and demoralising, requiring staff to work long nights and weekends while balancing an effectively full-time teaching load.

"Every time I’ve tried to seek support to meet these expectations I get knocked back, all the time, knocked back," she said.

James Neill, an assistant professor at the university who was hired before the scheme kicked in, said many of his colleagues were struggling, particularly women and those with young families.

"I'm in the same job but I have security," he said. "It's not fair. And we're working those hours to pick up the slack for the students because we don't want them to suffer."

Vice-chancellor Deep Saini is out of the country until next week, but has defended the program as "sector-leading" and similar to those in North America.

It is understood he has authorised the university's negotiating team to bargain with the union in his absence, and an offer from the university is listed on Thursday's agenda.

"We are looking forward to discussing the issues of concern for all staff, both academic and professional, when negotiations continue at the bargaining table tomorrow," a spokeswoman said.

Joining the union on Wednesday, the Greens' candidate for the seat of Canberra Tim Hollo said he was increasingly concerned about the industrialisation of the university sector, as subjects were slashed and academics expected to churn through more and more students.

"It's really stark here at UC at the moment," Mr Hollo said.

"We're turning universities into factories."

With Zain Waseem

Know more? sherryn.groch@fairfaxmedia.com.au