EARTHQUAKE UPGRADING OF UNREINFORCED MASONRY BUILDINGS

Unreinforced masonry bearing wall buildings, which are very common in Iran, have been widely recognized for their sustaining of life hazardous damage. This paper will provide guidelines for development of a method for strengthening of such existing buildings. The strengthening work can be performed in two steps. Step one will reduce the risk of the most probable types of failure at low cost by providing Tension Anchors, Wall Braces, Parapet Braces, and Veneer Ties. Step two will add more strength and integrity to the structure as a whole by Providing Tension/ Compression Chords, Intermediate Ties, Shear Bolts, Shear Anchors, Shear Walls, and Secondary Supports. The cost of seismic upgrading versus the potential for saving lives and properties will determine the level of earthquake reinforcement work.