I know that every country have is how brick measures. I asume that a "medium" brick have 2X7mm in 1/35 scale.

take a plate of cork of 2mm thick, and cut him in strips of 1mm wide(aprox) as you see in the picture. See that I not cut to very end of the cork.

cut these strips in 7mm bits

make a cardboard structure. These bits of cork must be glued here.

glue a paper to structure with lines in it for reference

arc of the bridge (really a sewer)

finished work

you must sanding all work

Now is time to imitate the concrete among bricks with a layer of plaste ror these prepared paste for repair walls before paint. Retreat excess before dry

The final result prepared for sea and paint.
These work take around 4 hours.Inot count time for dry glue
I hope that these images talk for himself.I will graceful if these photos can be posted in articles
Carlos