The upper structure of steel arch bridge is primarily composed of arch ring, suspension rod (or arch column), tie rod, bridge beam and other components. The general layout of rigid frame arch bridge depends mainly on bridge span and load size.

The bridge panel can be constructed using prefabricated micro-bending slabs with cast-in-place concrete filling layer and deck pavement, or alternatively with prefabricated hollow slabs combined with cast-in-place concrete layer and deck pavement.

• Section form: Steel box arch, steel pipe arch, steel truss arch
• Space posture: Parallel arch ribs, basket arch ribs, butterfly arch ribs
• Carriageway position: Upper bearing type, middle bearing type and lower bearing type arch bridge
• Boom layout: Parallel vertical boom, inclined boom, mesh boom

Simple system arch bridge: Only the arch ring serves as the main force component, forming a thrust arch structure where the arch thrust is directly borne by the pier or foundation.

Combined system arch bridge: Carriageway beam and arch work in combination to share the load.

Steel arches can be designed as truss arches, box arches, or plate arches. Truss arch bridges are particularly important for large span applications.

Key design parameters for long-span steel truss arch bridges include:

• Arch rib truss layout
• Arch axis configuration
• Vector span ratio
• Vault and arch foot height selection
• Boundary conditions
• Bar section form and area

Trussed arch ribs are classified by main truss frame type:

• K-type truss: Best mechanical properties
• W-type truss: Most economical with least steel usage
• P-type truss: Advantages in construction and aesthetics

The primary load-bearing member that mainly withstands axial pressure while also bearing partial bending moments. Available in box, pipe, and truss type sections, with trussed arches offering light weight, greater span capacity and good economy.

The force transfer component that transmits deck loads to the arch rib. Available as rigid (steel pipe/section steel) or flexible (high-strength steel wire bundle) configurations.

For non-thrust arches, the tie rod bears the arch's thrust through axial tension. Available in rigid and flexible configurations.

Essential for maintaining transverse stiffness and stability, cross braces come in various configurations including one-word, K-shaped, X-shaped, and meter-shaped supports.

Rise span ratio: Typically 1/4~1/7 for steel truss arches, with smaller ratios increasing horizontal thrust.

Arch axis: Common forms include arc line, quadratic parabola, and catenary for optimal force distribution.

Arch rib height: Variable height arches are used for large spans to optimize material usage.

• Constructed using high-strength steel as primary material
• Requires abutments at each end and supporting piers
• Various configurations available for different load requirements
• Optimized structural design for efficient material usage