Author

RAGHUNATH S.
BMS College of Engineering, Bangalore, Department of Civil Engineering
NANJUNDA RAO K S.
Indian Institute of Science, Bangalore, Department of Civil Engineering
JAGADISH K. S.3
RV College of Engineering, Bangalore, Department of Civil Engineering

Abstract

There have been many instances of un-reinforced masonry walls suffering severe out-of-plane damage during an earthquake, often leading to collapse of walls, particularly when the restraint at the top edge is inadequate. An alternative to the shaking table tests is to subject the wall to a series of controlled soft-impact loads. In the present investigation, in an attempt to improve the flexural ductility of masonry wall, an innovative method of introducing vertical reinforcement in masonry, has been tried. This reinforcement is provided at regular distances along the length of the wall and on both surfaces of the wall. They were tied together with the help of lateral ties passing through the bedjoints. When the wall the wall bends, the reinforcement on the convex surface withstands the tensile stresses and thus provides flexural ductility. Such vertical reinforcement which hugs the masonry wall is termed as “containment reinforcement”.
Two geometrically similar full-scale walls were subjected to a series of soft-impact loads and their relative performance has been compared. While one was an un-reinforced brick masonry wall the other was provided with conventional horizontal reinforced concrete bands and vertical “containment reinforcement”. The experiments have shown that vertical containment reinforcement is very effective in preventing out-of-plane collapse of masonry walls.

Key words
out-of-plane load, masonry wall, soft-impact load, containment reinforcement