A mass of blue and yellow overtook the intersection of Wilshire and Westwood boulevards near the UCLA campus on Wednesday. Protesters blocked traffic and held signs depicting skunks with the words "UC POVERTY WAGE STINK." Others read "UC: Pay workers enough to live" and "Our work makes the UC work."

Approximately 700 electricians, painters, plumbers, carpenters and other unionized UCLA skilled-trade workers are on strike to protest failed contract negotiations between themselves and the university.

"Our goal for today is simply to get the university to stop violating the law and to bargain in good faith, which they have not been doing," said Jason Rabinowitz, the secretary-treasurer and principal officer of Teamsters Local 2010, the union representing the workers since April 2016.

Rabinowitz is the lead negotiator of the union's eight-member negotiating committee, which is seeking a new contract for its members. Come 2017, the workers will have been without a contract for four years.

In a statement, UCLA said an initial bargaining session was held on Aug. 30.

"UCLA has since been bargaining in good faith with Teamsters for a fair contract for this employee unit," the university said. Ten bargaining sessions have already been held between the school and the union and "a mediation session involving both parties and a neutral mediator was held on November 9."

The university has proposed a total 24.5 percent wage increase over the next four years. Workers would receive an immediate 12.5 percent increase, followed by a 3 percent increase every year until the total is reached. In addition, the proposal includes a $1,000 signing bonus and retirement and health benefits.

Teresa Conrow, a union spokeswoman, told ABC News7 that workers in this employee unit "earn roughly $32 an hour, which is as much as $10 an hour less than what workers in the area are paid for the same jobs."

Based on this amount, a 12.5 percent increase would equate to a $4-an-hour raise; the full 24.5 percent increase would add $7.84 an hour.

Workers say UCLA's offer is unfair because they have not received a raise in nearly a decade.

"We're trying to hang on to whatever benefits we have and we want to get a raise to make up for all the years that passed that we didn't really get anything," said Richard Sunn, a maintenance worker of 14 years at UCLA. He said that the university increased pension, insurance and parking payments over the last decade.

"They're refusing to do a back pay or anything. So we're saying that they should give us a bigger piece upfront," Sunn said.

Rabinowitz estimated that the strike, which was scheduled to continue until midnight, drew 98 percent of the skilled-trade workers from UCLA. The university, in its statement, said it was concerned with the impact on its medical center, but chose to remain "fully operational."

"We turned back dozens of delivery trucks. We shut down construction sites," Rabinowitz said. "Hundreds of medical appointments had to be rescheduled or cancelled, and that's because the workers here are standing strong and united and are saying no on unfair labor practices."

On Thursday, 200 skilled-trade workers represented by the same union will be on strike at UC San Diego.

UCLAunionworkers

Reach Staff Reporter Magali Gauthier here, or follow her on Twitter.