Clients / Niagara Region, Welland

Location: Welland, Main Street Bridge, Ontario
Description: Heritage Lift Bridge Rehabilitation

  • Design Removable Anchor System for Multipoint Suspended Platform Design
  • Structural Steel Tie down Design to secure lift bridge during anchor bolt replacement
  • Temporary Access Bridge Design – Provide access fully loaded concrete truck


Access Bridge ViewThe East Main Street Bridge is located over the Old Welland Canal in Welland and has a significant heritage value. This project consisted of substructure concrete repairs, structural steel repairs and deck repairs.

Anchor ViewTamas Kalenda designed a multipoint suspended working platform under the entire bridge. The anchors were secured to the bottom flange of the stringers. The platform contained two different levels. The lower level – which was supported by the stringers – was installed about 500mm under the bottom chord of the main truss. The upper level – which was supported by the main truss and the most exterior stringers – was outside of the main truss. The upper level worked as a cantilever access platform below the walkway. Major Design was the anchoring system for the lower level in such way that – under certain conditions – an anchor could be removed and reinstalled later to accommodate the sandblasting and painting operation.

Structural analysis & calculations were needed for several different loads (heavy vacuum equipment, concrete mixer, storage area, etc…) locations on the top of the deck in addition to the load on the suspended platform. Extra care and planning was taken for possible location of different equipment and track routes to avoid any damage to the structural steel members.

Considering the Heritage and bridge year construction, research for the steel sections and material properties were required. This was really exciting and challenging, several different load combinations based on the Canadian Highway Bridge Design Code and structural steel analysis were needed to prove that the bridge was capable to carry the desired loads. These calculations were approved by two independent Professional Engineers and accepted by the engineering consultant.


Custom Achor DesignBasic parameters were:

  • Allow ±25mm longitudinal temperature movement
  • Allow ±10mm horizontal movement
  • 1350kN anchor force (vertical) per side (2700kN total)
  • ±700kN wind load (horizontal) located at the top of the end beams

Also designed for this Contract was a 7.5m long temporary access bridge as per the CHBD. The bridge was successfully used to provide access for several fully loaded concrete trucks and heavily loaded vacuum tracks.