EE AND TWO OTHER CO-WORKERS WERE ATTEMPTING TO POSITION A SECTION OF RAISE LINER (5'X4'LONG) TO THE UPRIGHT POSITION WITH A 3.5 YD LHD AND CHAIN AS THE LOADER BUCKET LIFTED THE RAISE LINER, TH E LINER STARTED TO ROLL OFF BUCKET. INJURED EE IN ATTEMPLING TO STABLIZE IT, WAS PUSHED AND FELL WITH LINER STRIKING R.L.