Triple Crown Services Company, an affiliate of Norfolk Southern Corporation, will expand its trailer fleet by 15 percent, spending $20 million, in preparation of an expected rise in freight. Triple Crown will buy 800 custom-built RoadRailer trailers and 250 rail wheel assemblies known as bogies. RoadRailers are enclosed truck trailers designed to transport freight on trucks and can be supported above rail track on the bogies for long-distance travel. The Fort Wayne company will spend $800,000 to double the size of its Wayne Trace maintenance facility, said President Jim Newton. The company, which employs 235 people in the U.S. and Canada, will hire 15 more people including 10 mechanics, according to a company statement.