A lane is blocked on I-75 in Hillsborough County after part of a tractor-trailer fell over the side on Monday.The Florida Highway Patrol said a 31-year-old man was driving the Conex trailer north on the ramp from I-75 to I-4 around 12 p.m. The left side of the tractor-trailer collided with the inside concrete wall, causing the trailer to overturn. The trailer then fell onto Hillsborough Avenue, hitting a 61-year-old woman who was driving a Jeep Grand Cherokee west.The tractor-trailer's driver was uninjured, but the Jeep's driver was seriously injured and taken to a local hospital.This is a developing story and will be updated when more information is available.