Repair of 7-Story Bearing Wall

Collapse of the brickwork facing on a seven story concrete unit masonry bearing wall revealed a condition of high overstress on the wall due to large openings. The wall was permanently shored by placing steel columns on the outside with long steel plates acting as springs to partially support the wall at each window head. To insure satisfactory performance, the completed structure consisting of both original and new construction was analyzed for the interaction between axial deformations of the steel columns due to load and thermal movements, deformation of the spring brackets, and necessary load relief to the existing masonry wall. Data for fabrication and erection instructions were compiled by electronic computer as the design equations were too complex to solve manually in a reasonable time. It is apparent that allowable bearing stresses for masonry walls contain a larger factor of safety than two and that highly overstressed, multi-story, bearing walls can be successfully repaired.