Analytical evaluation of repair and strengthening measures of Qasr al-Bint historical monument—Petra, Jordan

摘要

Repeated earthquakes and salt crystallization are the two most environmental factors that have contributed to the severe damage of the existing Qasr al-Bint monument over the past centuries of a complex history. This paper is concerned primarily with giving the historical monument Qasr al-Bint the ability to withstand future earthquakes without excessive damage. Alongside this primary objective, it takes into account others which stem from the particular characteristics and values that make this structure worthy of special attention, such as the symbolic value of the belief or purpose that gave rise to the original construction or the documentary value as a physical evidence in a more representative manner of the architectural or structural practices of a particular time (30 B.C.-40 A.D.) and place (city of Petra, Jordan). This implies a highly specialized restoration operation aiming to preserve and reveal the aesthetic and historical value of the monument and is based on respect for original material and authentic documents. Therefore, assessment of the earthquake resistance of such historical structure presents special problems on account of the way in which it was built and the materials used during the complex past history of successive changes and progressive deterioration [United Nations Industrial Development Organization. Building construction under seismic conditions in the Balkan region, vol. 6. Repair and strengthening of historical monuments and buildings in urban nuclei, Vienna: (UNIDO/UNDP); 1984]. In order to achieve these goals, full architectural, material, structural details, and present soil, foundation and structural condition supplemented by good photographic coverage are recorded due to close collaboration among structural engineers, architects, archaeologists and other professions with relevant complementary expertise. However, only structural aspects are of a direct concern here. Dynamic finite element analyses for both the existing monument with its current conditions and the proposed repaired one are performed. The results of these analyses are used to determine the type and the position of required works needed to repair and strengthen the structure against possible earthquakes. The results showed that the monument can be retrofitted and strengthened to some extent, such that it can resist moderate quakes and preserve its historical look and value.