New Integrated Knowledge based approachs to the protection of cultural heritage from Earthquake-induced Risk

The “Lost” Crusader Fortress
Engineering Survey
OrdererIsrael Government Tourist Corp. Ltd.
DurationFebruary – March 2003
Implemented by: Eng. Yardena Etgar
Eng. Eduard Kulik

An engineering survey was conducted in the “Lost Crusader Castle” located in the town centre of Tiberias, aiming to define a strategy for the stabilization and conservation of the site.
The earliest evidence for the fortress existence dates back to 1099 CE. Almost a hundred years later the southern Crusader castle was the residence of the governor of Tiberias: the Sovereign Princess Eschiva I of Galilée and Triberias. Saladin conquered Tiberias in 1187 CE and took control of the castle. When the army of the Emperor Frederick Barbarrosa arrived on the southern coast of Asia in 1190 CE, Saladin ordered his people to destroy fortified compounds. One of those was the southern castle of Tiberias.
Many of the buildings in Tiberias were destroyed by the earthquake of 1546. Even though there is no conclusive evidence of this, it seems the fortress was also damaged. Another earthquake in 1837 and a flood in 1934 destroyed the remains of the fortress. Following the flood of 1934, during the British Mandate, a promenade was constructed alongside the ruins.
The building measures c. 21.0 m long by c. 6.0 m high. The structure was built of basalt and has a barrel vaulted ceiling now partially destroyed. On its northeastern side is another cavity formed by a groined arch, 2.7 m high, atop of which is a kind of bema. The southeastern facade is a straight wall with no openings; there are two niches in the wall. The northwestern facade is a built wall with three openings. Other remains that are mostly destroyed are discernable to the west of the building.
At the moment, the building is abandoned and derelict. Cracks and the collapse of the walls were caused as a result of earthquakes and there are even apparent signs of vandalism. The engineering survey indicates that the walls of the building are stable, but there is a need to stabilize the openings. Moisture penetrating through the roof is washing away the bonding material from the mortar joints; the northeastern corner of the building collapsed, as well as both facades of the vault. There is a danger of further collapse. The interior cavity is destroyed and in an unstable condition. The later repairs that were carried out in the structure are damaging the original building materials.
In order to halt the destructive processes at the site it is necessary to carry out a number of conservation measures: pointing up the masonry joints and treating the cracks with a lime based bonding material; erecting a retaining wall in the northeastern corner; completing courses of stone work; completing debesh and sealing the tops of walls (coping); reinforcing lintels and doorposts; reconstructing the arches in openings; renovating the interior; removing poured concrete from the roof; completing the tiling and drainage of the roof; the masonry joints in the vault should be pointed after the roof is sealed.
It is recommended that the site be maintained on a permanent basis in order to prevent further deterioration of its condition.

To view the figures, click on the figure caption
1. General plan of the structure.

2. General view of the structure.

3. Northeastern facade.

4. Northwestern facade.

site built by tetitu