GWD-type Large-span Bailey Bridge

When a span exceeds the capacity of a standard Bailey bridge, the GWD-type large-span Bailey bridge serves as an ideal solution. As a long-span configuration within this product family, it is an extended, prefabricated truss bridge capable of spanning rivers, valleys, or railway corridors without the need for piers within waterways or floodplains. This is a critical advantage: poorly placed piers can obstruct navigation, impede flood discharge, or even interfere with ongoing construction activities beneath the bridge.
Traditional Bailey bridges often require support piers every few meters-an approach that is not only slow and costly to implement but frequently fails to meet hydraulic requirements. By adding only a modest amount of structural weight, the GWD-type large-span Bailey bridge significantly reduces the number of required supports. The result is a streamlined single- or double-span structure that can still be installed using the same assembly methods familiar to construction crews. It is a highly practical choice for projects that demand long, unobstructed spans without the need for a permanent truss bridge.

Single-span capability up to 90 m means no piers sitting in the stream or the valley floor. The gwd-type large-span bailey bridge makes this practical.

S460 steel lets you reach longer spans without the panels getting proportionally heavier.

Double- or triple-truss arrangements scale capacity up to truck and plant loads.

Incremental-launch erection keeps heavy in-water crane work off the critical path.

Duplex coating and concrete abutments give you a long, low-maintenance service life.

Works with bailey trestle piers when you need to stretch past a single span.

Deeper panel geometry buys the section depth that resists the big midspan moments.

The trick with this GWD bridge is the panel depth: by making each panel 2.0–2.5 m deep, you get a much larger lever arm between the top and bottom chords than a standard bailey offers. That depth is what lets one span cover 60–90 m without the chords overloading or the deck sagging. The gwd-type large-span bailey bridge is built for this.

Out on the job, a truck's weight lands on the deck and travels through the transverse floor beams into the paired (or quadrupled) longitudinal trusses. The diagonal web system then does the quiet work - it converts the bending moment into pure axial force, so the reinforced top and bottom chords only have to carry compression and tension. They're doubly reinforced because that's exactly where the demand peaks, right at midspan. Sway frames and wind ties keep the deep truss lines from racking sideways.

When it's time to build, we assemble the truss on one bank and push it out - cantilever style - with a heavy launching nose leading the way. It reaches across the gap until it lands on the far abutment. For the longer 150 m-plus crossings, we slip intermediate bailey trestle piers in to break the run into manageable simply supported segments.

A GWD bridge is a deep through-truss girder built from standard panels pinned end-to-end, with doubly reinforced top and bottom chords that take the peak midspan compression and tension. The paired or quadrupled longitudinal trusses carry the load through a diagonal web system that converts bending into pure axial force. Transverse floor beams spread vehicle weight into the trusses, while sway frames and wind ties keep the deep truss lines from racking sideways. At each end, fixed, guided, and rocker bearings sit on reinforced concrete abutments and pass the reaction down into the foundation. Continuous steel deck panels, with an optional asphalt wearing course, form the running surface on top of the floor beams. 

You'll see the GWD dropped in for single-span crossings over wide, navigable rivers where piers aren't an option; temporary bridges during major replacements when in-water piers are banned; long crossings over railway corridors, highways, or industrial plants; emergency long-span bridges after floods or earthquakes; and access bridges at dams, reservoirs, or coastal sites where a pier would just get in the way.