Prospects for industrial peace in Grocon construction sites appears bleaker as the Construction, Forestry, Mining and Energy Union (CFMEU) disclosed plans to further prolong the ongoing strike which on Thursday entered its ninth day.

Bill Oliver, state secretary of CFMEU warned the state government that the union has 1,000 members at the Emporium building site ready to continue their blockade for 40 to 400 days or as long as it takes.

"The message to Baillieu in Sprint St is if he wants to bring in the coppers with their batons and their horses then bring it on because there are 11,000 police and there are 30,000 members of the CFMEU and . . . we're ready to rumble," Courier Mail quoted Mr Oliver.

The protest over safety conditions is ongoing while talks between Grocon and CFMEU officials will be held at Fair Work Australia in Melbourne on Thursday.

An alliance of four major construction unions, Building Industry Group, is also holding on Thursday its meeting in Carlton to vote on another large strike that could result in work stoppage by 150,000 construction workers in a statewide protest.

In New South Wales, Brian Parker, CFMEU state secretary, said the union would follow the injunction issued by the NSW Supreme Court that set a 100-metre union exclusion zone around the Grocon site in Castlereagh Street in Sydney.

Grocon, Australia's largest privately owned builder, warned that the company's future will be placed in peril should the industrial action on its various sites prolong, said Grocon Chief Executive Daniel Grollo.

Grocon sent home on Wednesday its workers at its $800-million office tower project in Castlereagh after CFMEU members blockaded the site in the morning and destroyed the gate locks.

Mr Grollo described the level of intimidation, threats, bullying and disregard for the law at Grocon construction sites as the worst he had witnessed in the 22 years that he has been in the construction industry.

Grocon has 400 construction workers and a pipeline of $2.6 billion worth of projects. Mr Grollo said he hopes to recover from CFMEU through the courts the millions of dollars that Grocon has lost due to the prolonged strike.

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