Study on Behavior of Unreinforced Masonry Walls

International Journal of Biotech Trends and Technology (IJBTT)
© 2013 by IJBTT Journal
Volume - 3 Issue - 1                          
Year of Publication : 2013
Authors :M.Kirubakaran, R.Sridhar, Dr.E.Chandrasekaran, T.P.Meikandaan

M.Kirubakaran, R.Sridhar, Dr.E.Chandrasekaran, T.P.Meikandaan "Study On Behavior of Unreinforced Masonry Walls",International Journal of Biotech Trends and Technology (IJBTT), V3(1):28-33 Jan - Mar 2013. Published by Seventh Sense Research Group.


Masonry is one of the oldest construction materials. Masonry structures have been in existence since the earliest days of mankind. Clay units have been in use for over 10,000 years and Sun dried bricks were widely used. Unreinforced masonry structures are most vulnerable during an earthquake. Normally they are designed for vertical loads and since masonry has adequate compressive strength, the structure behaves well as long as the loads are vertical. When such a masonry structure is subjected to lateral inertial loads during an earthquake the walls develop shear and flexural stresses. The strength of masonry under these conditions often depends on the bond between brick and mortar (stone and mortar), which is quite poor. This bond is also often poor when lime mortars and mud mortars are used. A Masonry wall can also undergo plane (in-plane and out of plane) shear stresses if the inertial forces are in the plane of the wall. Shear failure in the form of diagonal cracks is observed due to this. However catastrophic collapses takes place when the wall experiences out-of-plane flexure. This can bring down a roof and cause more damage. Masonry buildings with light roofs such as tiled roofs are more vulnerable to out-of-plane vibrations since the top edge can undergo large deformations. It is always useful to investigate the behavior of masonry buildings after an earthquake, so as to identify any inadequacies in earthquake resistant design.


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Studying types of masonry construction, their performance and failure patterns helps in improving the design and detailing aspects.