BLACKSBURG — Duke Johnson ran for 249 yards and scored two touchdowns and Miami took advantage of Virginia Tech's fumbles on three straight second-half drives in a 30-6 victory Thursday night.The Hurricanes (5-3, 2-2 Atlantic Coast Conference) outgained Virginia Tech 255-36 in the first half in taking a 24-0 lead, then took away the ball on the Hokies' first three drives of the second half.