Infrastructure engineering and construction firm CB&I (CBI) announced in a press statement Wednesday that more than 90% of shareholders  voted to approve the company's planned acquisition of Shaw Group (NYSE: SHAW).

Shaw's shareholders still must vote on the acquisition , which requires 75% shareholder approval, on Friday. If approved, CB&I expects the takeover to be completed sometime in early 2013, pending any remaining purchase requirements.

The purchase, originally arranged in July, saw CB&I offer $3 billion  to Shaw to create one of the largest energy infrastructure engineering and construction firms in the world. CB&I said then that it plans to run Shaw as its own business unit, maintaining the Shaw brand and capitalizing on its resources and synergies. Shaw's acquisition is expected to add significant capabilities in power generation, manufacturing, and more to CB&I's business portfolio.

Shares of CB&I rose on the news, gaining more than 4% in mid-afternoon trading.