UNESCO
ANCIENT MONUMENTS
OF THE ARCHAEOLOGICAL SURVEY OF INDIA
all photographs (except as marked) © by Randolph Langenbach / UNESCO, 2001
Click on photos to enlarge
The collapse of the Raolakha Chhatri
1)
BEFORE
2) AFTER 
(1-2) BHUJ: The Raolakha Chhatri was constructed in the 18th Century and survived the great 1819 Kachchh Earthquake, but succumbed to the 2001 Earthquake. It was the oldest, largest and most elaborate of these cremation ground memorials to past Maharajas. (Before photograph (right) courtesy of the Archaeological Survey of India, (left) courtesy Azhar Tyabji, Ahmedabad)
3)
(3) L.P.R. Mohnani, Deputy Superintending Archaeological Engineer for the Archaeological Survey of India is standing at what had been the apex of the dome of the Raolakha Chhatri. Rather than collapsing by tipping over, as one may have expected of the open pavilion-like structure, the stones of the dome and the post and beam structure simply vibrated apart until they lost their purchase, causing a progressive collapse. The ruins of the dome remained perfectly in the center, with the perimeter columns falling outward in all four directions. For a partial collapse of a similar type of structural system, which gives evidence of how this collapse occurred, see the Saiyed Usman Tomb, in Ahmedabad and the Babalauli Mosque in Ahmedabad.
4) 
5) 
(4-5) The collapsed Rajolati Chatri is on right in the left image, and the right image illustrates the remains of two of the twelve smaller domes, which are revealed as having been solid masonry, and thus very heavy. The later smaller chhatris which survived the earthquake are visible behind. These others survived despite their lack of any internal or external walls.
6) 
7) 
8)
9)
(6-9) This smaller chhatri was damaged, but not destroyed by the earthquake, despite the fact that it contains no shear walls or other lateral support. The damage provides a clue as to the process of the destruction of the larger Raolakha Chhatri. The earthquake shaking has caused the stones to vibrate apart because of the lack of ties to hold them together. The use of iron cramps to secure individual stones together as a protection against earthquake damage can be found in use as early as the ancient Greeks who secured the stones of the Parthenon and other structures in this fashion.
It is interesting and important to observe that this did not collapse by being thrown over, despite the violence of the shaking at Bhuj, and the lack of shear walls. Clearly the structure rocked back and forth, but the "restoring force" of gravity on the columns was sufficient to allow it to remain standing. In fact, there were many open post and beam pavilions here and in Ahmedabad, which were affected by the earthquake, but none failed by being thrown over. This record can provide support for the retention of the open pavilion design of the structures when they are restored, with seismic hazard mitigation being most effectively applied by developing a plan to tie the stones together to prevent the spreading that has been observed here and in Ahmedabad.
10) 
10) These stones are from the cupola on a 19th Century Chhatri which did collapse. In this structure copper dovetails and rods were introduced to tie the stones together (the dovetail is visible to the left of the rod). The structure collapsed most likely from the shear failure of its very thin stone columns.
11) 
12) 
13) 
14) 
11-14) This ancient stone Shiva Temple in Kotay, a small village to the north of Bhuj, is under the protection of the ASI. It was under restoration at the time of the earthquake. The earthquake damage was limited to the shifting of some of the stones on the front, and spalling of some of the columns on the interior. There were also some slight opening up of the mortar joints in the walls. Fortunately, the on-going restoration can now include the repair of the earthquake damage. The damage can be seen in (12) and (14). The new stone for the restoration work seen in (13) was prepared prior to the earthquake to replace badly deteriorated sandstone.