The CFMEU and 19 of its officials have been slapped with a $817,500 fine over building site shutdowns that saw unionists block cars and call workers "scabs, grubs and dogs".

The 2013 campaign of intimidation was aimed at construction company John Holland Queensland, which had refused to sign an enterprise agreement with the union.

Work stoppages took place over several months at two construction sites — the $777 million Enoggera Army Barracks and the $60 million QUT Kelvin Grove Campus.

The Federal Court hearing into industrial action was provided with video of unionists standing in front of cars at the QUT site and preventing workers who wanted work from accessing the site.

They carried signs labelling workers as "scabs and dogs".

One sign read "This is why you are on $19 an hour u gutless grubs, scabs an (sic) dogs. Weak as piss."

The CFMEU has been fined $551,900 for 26 breaches under the act. ( ABC News: Matt Watson )

Another taken on November 18, 2013 read: "No EBA, grubs, grubs, grubs, grubs, grubs, grubs, grubs."

When work first stopped at the QUT site on March 8, 2013, it is alleged CFMEU assistant state secretary Jade Ingham warned the head contractor's operations manager: "this is just the start of it, the sooner you sign the agreement the sooner it will stop".

The stoush only ended when John Holland management finally caved in and signed a CFMEU enterprise agreement.

Union behaviour of intimidation 'flagrant and systematic'

In handing down the penalty, Justice Darryl Rangiah said the union's conduct was "deliberate, flagrant and systematic".

"Their breaches of the FWA [Fair Work Act] must be regarded as very serious and deserving of very significant penalties," he said.

"The contraventions affected two major projects and impacted upon a large number of subcontractors and workers.

"The behaviour of the respondents who contravened s343 of the FWA was confronting, threatening and intimidatory.

"Their conduct involved a sustained and flagrant disregard for the workplace rights and freedom of association guaranteed under the FWA."

He said the union argued its conduct was a "legitimate industrial objective", namely making an enterprise agreement.

However, Justice Rangiah said under the FWA: "particular conduct is made unlawful, regardless of whether or not the contravener is pursuing what it perceives as a legitimate industrial objective."

"I do not accept that the fact that the respondents were pursuing an EA makes the offending less serious, particularly when it was designed to coerce JHQ into agreeing to the CFMEU's terms.

"The respondents have shown no contrition or remorse for their actions."

He fined the union $551,900 for 26 breaches under the act.

The 19 union officials, including secretary Jade Ingham were fined also with amounts varying from $37,500 to $3,600, taking the total to $817,500.

Justice Rangiah said he did not consider the aggregate penalties "oppressive or crushing" and saw no reason to reduce them.

It is unclear if the CFMEU will pay the entire amount. The union has been contacted for comment.

ABCC 'welcomes' Federal Court penalties

The Australian Building and Construction Commission (ABCC) has welcomed the Federal Court penalties, saying it sent a strong message "that coercive and intimidatory behaviour will not be tolerated".

Commissioner Stephen McBurney said "the sustained campaign on the head contractor impacted important major projects and risked the livelihoods of those who wanted to work".

"The level of intimidation directed at both the head contractor and the workers is alarming," he said.

"This was a protracted campaign orchestrated by repeat offenders intended to force the company to sign a CFMEU enterprise agreement."

The ABCC lodged an application in 2016 to fine those involved in industrial action at QUT and Enoggera army barracks for 97 days in 2013, alleging it was a targeted attack on developer John Holland over an enterprise agreement.

The case was leapt on by the Turnbull Government last year to bolster its fight to re-establish the ABCC.