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Bats and Dippers in Bridges in Ireland

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Apologies for quality of images, I only have colour photocopies of the original to work with :-(
Upstream elevation after completion of the works. Downstream elevation immediately prior 
to completion of the works.
Scaffolding almost disassembled; 
temporary cofferdam still in place. Settlement at the East Corner of the South abutments.
The corner was underpinned and a plinth constructed along the length. Pressure grouting the South abutment;
The work is observed by a member of the 
local bat group (far right) Longitudinal cracking of the arch barrel caused by settlement of the East side of the South abutment.
Voids with the crack inhabited by bats and dippers are marked with white paint. Close up veiw of voids in the arch masonry occupied by bats.
These holes would be preserved. Dipper hole in the arch which was preserved 
during pointing and pressure grouting. A dipper hole and close up view of a dipper hole 
formed in the arch during the works. Close Up of the bat hole (centre)
formed in the arch by removal of existing masonry,
forming a void and replacing masonry. Drilling holes in masonry for stitch bars.
The positioning of the stitch bars along the longitudinal crack was considered when deciding which voids should be preserved. Stich bar in position prior to pressure grouting. Fixing the 600mm x 600mm plaster board slab to the soffit of the arch.  The slab was intended to accommodate bats. Slab camouflaged with (still wet) mortar.
Only one edge of the slab is open to allow access. Slab on arch soffit.
Opening is on right hand side.
A dipper hole can be seen just below the slab.

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