A joint venture of Tutor Perini Corp. has won an $80 million judgment in a long-standing fight with the Massachusetts Department of Transportation (MassDOT) over its Central Artery/Tunnel Project in Boston, commonly called the Big Dig.

The Sylmar civil engineering and construction firm has been locked in a battle with the department for more than 15 years. The project was developed by the Perini-Kiewit-Cashman joint venture, of which Tutor Perini had a 56 percent interest.

The fight was over a number of claims for more work time and payment to the joint venture for the project. During the construction, MassDot ordered changes, but did not compensate for time delay and inefficiency, according to the joint venture’s complaint.

After a three-member Dispute Resolution Board originally sided with the Tutor joint venture, MassDot successfully argued in court that the board had overstepped its authority. But this week, Massachusetts Superior Court Judge Thomas P. Billings affirmed the board’s original decision, granting the venture more than $80 million in rewards.

But Tutor Perini Chief Executive Ron Tutor said the issue isn’t fully resolved.

“This still leaves substantial additional non-binding DRB awards to be either adjudicated or resolved between the parties,” he said in a statement. “This decision certainly vindicates our position and the vigor with which we pursued this litigation over all these years.”

The Big Dig project rerouted the Central Artery (Interstate 93) — the chief highway through the heart of Boston — into a 3.5-mile tunnel. The work took about 15 years and concluded in 2007. Its estimated cost is more than $14 billion.

Along with Tutor, Jay Cashman Inc. of Quincy, Mass. and Kiewit Corp. of Omaha, Neb. were partners in the joint venture.