R20: quick-repair-mortar
R20 broken channel
R20 crack-reconstructing
R20 pipe bracket encasing in concrete
R20 installation of a STZ-carapace
R20 pipe end reconstructing 1
R20 pipe end reconstructing 1
R20 shaft-reconstructing 1
R20 shaft-reconstructing 2
R20 shaft-reconstructing 3
R20/10 filling fugues of a leaky cistern
R20/40 hospital Tournelles
R20 - KA20 channel-crossing