(By Rick Rothacker, rrothacker@charlotteobserver.com) Charlotte-Mecklenburg police have closed Stonewall and Tryon streets around the Duke Energy Center because of ice falling from the 48-story office tower.Thin slivers of ice are flaking off the building, hitting the street and part of the building below. Police have taped off Stonewall between Church and Tryon streets and Tryon street around the base of the building.