Self-supporting form for arch bridges

Construx supplies an arch bridge formwork for several standardised Infrabel bridges

This formwork is self-supporting and sits only on the abutments at either side of the railway tracks. The formwork is modular and the idea is to pour each bridge in 2 or 3 stages. The formwork is to be rolled to the second phase after striking the first phase. 

The railway track is not put out of service for fixing steel and pouring concrete. Only whilst assembling and disassembly, the tracks are put out of service at night, for 3 hours.

Details largest bridge:

• Width on top 10m, width at the base 20,8m
• Span 20,3m, arch length 25,6m

Assembly, striking and moving procedure:

• Assemble arches per 2 sections, strips of 25,6m long
• Lift the strips over the railway tracks using the crane
• Bolt 3 strips together using continuous tie-rods
• Fit the 2 triangular wings of 6m long x 3m wide
• Lift the complete set using jacks and support it with spindles
• Fix both sides against the abutments
• Fit side-forms, fix steel, pour concrete
• Release horizontally, strike the spindles and lower the complete form
• Move to 2nd phase using 2 winches

Details of the formwork:

• 3 strips of formwork 25,6m long x 2,5m wide, supplied in 6 equal parts
• Reinforced transitions at the joint of the  2 arches
• 2 triangular wings of 6m long x 3m wide
• Scaffold unit to join the strips
• Double bended side-forms on the outside
• Single bended side-forms in the middle
• Striking devices at both abutments
• Supports with wheels and spindles, rails, winches and jacks to demould, move and lift the formwork