Qingdao Jiaodong International Airport – Large‑Span Prestressed Roof Structure
Qingdao Jiaodong International Airport is a world‑class aviation hub in Shandong Province, China. The terminal building features a large‑span prestressed concrete roof structure with a maximum span of 72 m, using a beam‑slab system with bonded post‑tensioning. The total construction area exceeds 500,000 m², and the roof structure was designed to achieve long spans with minimal material consumption while ensuring high durability and seismic performance.
Prestressing technology was extensively applied in the main hall beams, transfer girders, and foundation slabs to control deflection, eliminate cracking, and reduce structural thickness.
🛠️ Construction Challenges & Prestressed Solutions
| Construction Challenge | Description | Prestressed Solution |
|---|---|---|
| Ultra‑long span terminal roof Main span up to 72 m | Conventional reinforced concrete would require excessive beam depth (4 m), increasing weight and reducing clearance. | Use bonded post‑tensioning with multi‑strand tendons (1860 MPa); parabolic tendon profiles balance dead and live loads, reducing beam depth to 2.5 m (‑38%). |
| Fast‑track construction schedule Multiple contractors working simultaneously | Traditional cast‑in‑place secondary beams lengthen critical path.电子 | Adopt precast prestressed double‑T units for secondary beams and parking decks; off‑site prefabrication shortens on‑site erection time by 28%. |
| Cracking control in massive slabs Slab thickness up to 1.8 m | Hydration heat and shrinkage cause high tensile stresses, leading to early‑age cracking.电子 | Incorporate unbonded post‑tensioning tendons in roof and floor slabs; impose pre‑compression to offset tensile stresses from hydration heat and shrinkage. |
| Coordination with MEP systems Dense MEP ducts | MEP ducts conflict with conventional reinforcement, requiring thick slabs and complex coordination.电子 | Use flat post‑tensioning slabs with unbonded strands; tendons placed around MEP openings, reducing beam depth and simplifying coordination. |
| Long‑term deflection & durability Creep, shrinkage & marine environment | Creep and shrinkage cause progressive deflection; de‑icing salts and sea air increase corrosion risk.电子 | Specify low‑relaxation strands (≤2.5% at 1000 h); use epoxy‑coated strands or fully grouted bonded tendons with corrosion‑inhibited grout for 100‑year design life. |
| Vibration control under jet blast Dynamic loads from aircraft engine exhaust | Large‑span roof must resist dynamic excitation, affecting passenger comfort and structural fatigue.电子 | Optimise tendon layout to increase natural frequency; apply staged tensioning to improve stiffness and reduce vibration amplitude. |
Prestressed solutions applied to main hall beams, secondary beams, and massive slabs
✅ Achievements & Summary
Through the application of advanced post‑tensioning technology:
· Achieved 72 m clear span with beam depth reduced from 4 m (conventional) to 2.5 m, saving over 40% concrete volume.
· Zero cracking observed in the main hall roof and transfer beams.
· Reduced on‑site construction time by 28% using precast prestressed double‑T units.
· Fully compliant with Chinese airport terminal design codes and international durability standards.
Qingdao Jiaodong International Airport demonstrates how modern prestressed solutions enable ultra‑large‑span public infrastructure to be built efficiently, economically, and durably, setting a benchmark for future airport terminals.
