African Design Magazine November 2015 | Page 29

African project Ethiopian Airlines Hangar of tensioned cables and struts. The pre-tensioned cables effectively formed a net of diagonal ties throughout the roof at top chord level. The purlin system comprised specialised MetSec 12.5m span sleeved z-purlins, provided by Safintra South Africa. The arch foundations consisted of reinforced concrete pad footings with deep shear keys to resist the arch thrust. The Black Cotton soil type found on the construction site was replaced with selectable material up to a depth of 2.5 m in order to counter the potential heave. All structural steel for the hangar was sourced from Italy and imported via the Port of Djibouti, from where it was road-freighted to Ethiopia. Efficient ordering of the structural steel was achieved by means of Strucad 3D structural steel detailing software, which outputs comprehensive material ordering schedules. The purlin system consisted of specialized MetSec 12.5m span sleeved Z-purlins, provided by Safintra South Africa. Hatch Goba was appointed as the structural and civil engineer on the project by client Elmi Orlindo Construction for Ethiopian Airlines. It provided full structural and civil africandesignmagazine.com 29