Key Control Points For The Core Installation Process Of Bailey Truss Bridges

After preparing components such as Bailey panels, the critical installation phase begins, where precise control over accuracy and structural mechanics is especially important.

The main bridge erection methods: The choice of method should be adapted to local conditions. The most commonly used method is the "cantilever push-out method," which enables quick and safe bridge construction without requiring large lifting equipment. When site conditions permit and components can be divided into larger units, the "full-span lifting method" may be adopted. In waterways or gorges where fixed tracks cannot be installed, the "floating transport and erection method" or cable-stayed lifting system can be selected.

Key connection details:
Reinforced chord installation: Ensure the installation of reinforced chords, with local reinforcement at support locations. During assembly, pay attention to distinguishing between upper and lower chords (the upper chord is typically 2 mm longer) to create a pre-camber that counteracts deflection under load.

Bére pin connection: Bére panels are connected using pins; striking or forcing them is strictly prohibited. If the hole misalignment exceeds 1 mm, the cause must be identified and the holes should not be forcibly enlarged. After installing all pins, safety locking pins must be properly engaged.

Torque and Anti-loosening: All bolted connections shall be tightened using a torque wrench in two steps-initial tightening and final tightening-to ensure the torque meets design requirements.