Engineering the reconstruction of Hawrān’s Ecclesiae during late antiquity: case of Julianos church in Umm el-Jimal, Jordan

Abstract This study challenges the stylistic-based classical prototype of the early Byzantine churches in the basaltic Hawrān region in the Middle East- the birthplace of Christianity and home to the world's most ancient Christian architecture and engineering ideologies. We focus on the engineering of the apsidal zone and its structural and architectural implications in relevance to the prototypical arcuated one. The instrumental case of Julianos Church in Umm el-Jimal provides an insight into the effect the local material and structural technique have on the formation of complex roofing structures for the apsidal zone. The detailed interpretation of the structural engineering reconstruction is coupled with historical research and digitally generated 2D and 3D reconstruction models. The findings indicate that the apsidal zone's engineering could have responded to Hawrān's unique material, structural techniques, and seismic measures. We finally compare the early twentieth-century scholars' stylistic-based interpretation of the apse roof to contemporary engineering-based reconstruction research based on historical evidence and contextual studies. Future researchers and conservators should consider a holistic approach that balances stylistic/engineering reconstruction processes carefully and numerically. The builders of Hawrān should have introduced novel engineering of their ecclesiastical architecture that differs from its 'classical' counterpart.