text: Gavin Roberts, 28, died of a brain injury on 15 June, four days after the collision on the A34 near the Compton junction in Oxfordshire.
  Megan Williamson's petition calls for the speed limit to be reduced.
  One month on from the crash that killed him she said "changes need to be made".
  "I just knew that Gavin would not want anybody to suffer as we have," she said.
  She wants the speed limit reduced from 70 mph to 50 mph, saying "people treat it like a motorway and it is a very narrow road".
  "There's no hard shoulder either, so if there are any accidents the emergency vehicles find it difficult to get down there."
  Mr Roberts was originally from Australia but had recently moved to Swindon where he worked for Network Rail.
  On the night of the collision, a Vauxhall Corsa travelling southbound smashed through the central reservation and into the path of Mr Roberts' BMW.
  Richard Hayes, the chief executive of the Institute of Highway Engineers, said Ms Williamson's suggestion would make the road safer, and called for the A34 to be upgraded.
  He added: "I'm absolutely sure [the barriers] are not as integrated as they should be... and that may well be eased by reducing the speed limit."
  The carriageway was closed 15 times in 2015 due to fatalities or injuries, and 56 times in the last five years, Highways England confirmed.
  A spokesman said safety was its top priority, and that it monitored the A34 on an ongoing basis.
  "Our thoughts go out to all those affected by the recent tragic incident," he said.
  Thames Valley Police said no arrests had been made following the collision and it was still appealing for witnesses.
target: The girlfriend of a man who died on a stretch of road where more than 50 people have been killed or injured in the last five years has called for tougher speed restrictions.