A roof fall occurred on the South Mains ""A"" beltline at 69 x-cut. The fall is approx. 40 feet long by 18' wide and 9' high. Area was bolted with 8' Install 3 bolts and resioned. Other support that were installed were 4"" H-beams and cribs. Cause of this fall was deterioration of the main roof due to weathering.