A tractor-trailer carrying a large cement block hit the overpass on westbound Interstate 635 at North MacArthur Boulevard Thursday evening, according to Irving Police. No injuries have been reported. The westbound lanes of 635 and N. MacArthur Blvd over 635 will be closed until TxDOT can make an assessment, police said. According to Irving Fire, the 18-wheeler struck the bridge which may have caused structural damage. Irving Fire reported the driver of the tractor-trailer to be OK. There is not an estimated time when the roadway will reopen, according to Irving police and fire departments.