Bhatar / Hatıl
Bhatar is a Pashtoo word describing timber beams with cross sections of approximately 10 x 10 cm. By extension the word Bhatar stands for a building technique where ladder-like elements made out of such timber beams are placed into the stone walls at regular vertical intervals.
In Turkey the timber beams of the ladder-like reinforce-ments are called Hatıl. This technique has been used throughout the Ottoman empire, thus can frequently be found in Macedonia and other areas of the Balkans. Timber reinforced stone masonry does exist all around the Mediterranean where it is not only used to improve earthquake resistance of buildings but to contrast differential settlements on soft soils.
Reinforcing stone masonry with horizontal timber
elements to make them more fit to resist earthquakes is quite an old idea. In fact, traces of timber lacing have been found in Minoan palaces of Crete from 2500 BC.
The Cator and Cribbage technique typical of the Baltistan region of northern Pakistan is a closely related construction method. The corners are well defined by short stacked pieces of timber (cribbage) interlaced with the lengthwise timber beams embedded in the stone walls.
Finally, the continuous multiple layers of bricks in stone masonry used by the Romans and known as opus listatum, may have had a similar role as the timber reinforcements: providing continuity and coherence to the walls.
This shake table demonstration and video have been prepared by the Nepalese Society of Earthquake Technology NSET for the sensitization of the people of Muzaffarabad as part of their reconstruction training in the aftermath of the 2005 earthquake.
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