Life cycle assessment of production and transportation-related environmental performance of steel in dome construction: a case study from Türkiye

The environmental footprint of structural steel depends on both production route and supply distance, yet their relative weight is rarely quantified for real projects. This study quantifies this trade-off for a steel dome project in Ankara, Türkiye, through a cradle-to-site life cycle assessment following ISO 14040/14044 and EN 15804, for a functional unit of 1 tonne of hot-rolled sections delivered to the site. All characterised factors were taken from published, independently verifiable sources — a third-party-verified BF-BOF sections EPD and the worldsteel sections eco-profile, both reporting CML (EN 15804+A1) indicators — rendering every result reproducible. Three scenarios reflecting real mill locations were compared: primary-route (BF-BOF) sections transported 130 km, and scrap-based EAF steel, conservatively represented by the market-average profile, transported 370 km and 790 km. Replacing the primary-route material reduced production-stage impacts by 22% (GWP), 40% (AP) and 38% (EP), whereas transportation impacts rose 6.1-fold across 130–790 km while remaining below 3.6% (GWP) and 4.8% (EP) of the cradle-to-site total. The break-even haul distance, approximately 6.0 × 103 km, is 7.6 times the longest domestic haul. Production route rather than transport distance therefore dominates the cradle-to-site footprint, supporting prioritisation of recycled-content (EAF-based) steel in regional procurement, subject to confirmation with plant-specific EPDs. Yapılan kısaltmalar: “for a steel dome project in Ankara” ifadesinden “project” korunup cümle sadeleştirildi, “increased” → “rose”. Toplam 217’den 199 kelimeye indi. Daha agresif bir kısaltma gerekirse veri kaynağı cümlesi (3. cümle) yaklaşık 12 kelime daha kısaltılabilir, ancak metodolojik şeffaflık vurgusu zayıflar — hakem değerlendirmesinde bu cümlenin değeri yüksek olduğu için dokunmadım.