North East Link – Grimshaw Street Bridge, Watsonia

Cerecon Engineering conducted an extensive inspection and structural assessment of the Grimshaw Street Bridge, a concrete and steel girder structure spanning the Hurstbridge Rail Line. Carried out for Acciona as part of the North East Link Program (NELP), the assessment confirmed the bridge’s readiness for construction activities – specifically the movement and positioning of a 62-tonne piling rig.

Originally constructed in the 1970s and modified in 2001, the bridge has a composite deck of reinforced concrete on steel I-girders. Cerecon performed a two-stage inspection covering the deck, abutments and wing walls: the first from road level to assess the deck’s condition, and the second during a rail occupation for a closer look at the structure beneath the bridge.

A 3D grillage model then simulated the load effects of the piling rig, considering dead loads from the bridge’s components, live loads from construction equipment and dynamic impacts from the rig’s movement. The findings showed the deck and girders could safely support these loads. Minor defects were noted on the abutments and wing walls, but none significant enough to affect load-bearing capacity.

Based on these findings, Cerecon recommended restricted loading paths and confirmed that no additional strengthening was required for the bridge deck. We coordinated closely with the client on safe positioning of the piling rig and ongoing monitoring during operations – keeping infrastructure safe and functional amid large-scale construction.