anchoring natural limestone panels to backup wall

[klx300r]

I have a building that was built in the early 50's, 2 storey, with 4 inch thick natural limestone slabs forming the exterior walls. The structural framing is steel with OWSJ's. The problem I have is that the stones at corner & roof locations have dislogded/shifted. A test cut at the roof revealed that very minimal cinch anchors were present at the 2 wythe masonry back up wall/stone panels. I have no drawings for the building but assume there are no lintels along the floor slab locations as the floor slab above the metal deck is typically 2 to 3 inches? The panels are typically (37.5" x 53.5").
What type of anchorage can I use to attach the limestone panels to the backup wall assuming that they will be taking all the deadload of the panels ie.no lintels at floor slab locations? A detail of the roof level is attached.
any help is greatly appreciated!

 

[csd72]

Not sure, but I believe that limestone is one of these materials that tends to creep over time. Your connections need to allow for that.

 

[hokie66]

Suggest you contact the Indiana Limestone Institute for assistance. This is a specialised area of facade engineering, and few engineers have this type of experience.