Structural Design Regarding Long-Span Outdoor Corridors of Langfang Airport Economic Center

In order to satisfy both architectural and structural needs and to avoid disadvantages of single form, complexity and high cost, the long-span outdoor corridors of Langfang Airport Economic Center project innovatively adopted the curved-shape truss with fixed condition. In view of the stress distribution, the overall stability of the truss, the local stability of the joints and the seismic performance of the structure, YJK 2.0.3 was adopted for comprehensive calculation considering dead, live and temperature loads; SAUSAGE 2020 was adopted for stability analysis based on direct analysis method with initial imperfection according to first linear buckling model, considering geometric and material non-linearity together with non-uniform distribution of live loads, within which truss with or without concrete slab were both accounted.YJK 2.0.3 was adopted for earthquake static analysis; SAUSAGE 2020 was adopted for dynamic time history analysis subjected to severe earthquake records, from which structural deformation, plastic damage and weak components were found out. ANSYS R19.2 was adopted for finite element static analysis towards the most heavily loaded joint using solid element and considering geometric and material non-linearity.
Following statements were concluded. Changing shape of the truss is closely associated with bending moment diagram of the truss and stress ratio of steel components is within control. Effects of concrete slab on global stability are obvious. Due to enhancing effects from slab, critical buckling mode changes from lateral deformation of upper layer of truss to bi-axial deformation for column. Comprehensive index, stress ratio and reinforcement ratio from seismic design was satisfied. There is no vulnerable spot and plastic damage under severe earthquake was limited. Peak stress around joint is less than steel yielding strength and area with stress concentration reduced rapidly. There was certain amount of sufficiency in joint capacity, and local stability can satisfy code limit. Enhancing measures were adopted in construction drawings according to previous analysis results.