What I did: I made the detailed design and work supervision of the installation, by hybrid pipe jacking/down-the-hole concentric air hammer technique, of three DN300 (12”) steel casings and the installation, by slip-lining, inside the 12″ steel casings, of three HDPE DN280 (11″) pipes, for the crossing of a rocky hill – Length of each crossing: 106,0 meters. The HDPE DN280 pipes, installed inside the 12″ steel casings, were used by SIEMENS to lay hi-tension electrical cables. A MITSUBISHI ULTRA MAXBIT 12″ were used to perform the boreholes.
HYBRID PIPE JACKING/DTH CONCENTRIC AIR POWERED HAMMER TECHNIQUE
What I did: I made the detailed design and supervision of the installation by microtunneling and HDD, in very hard and abrasive quartzite-diorite rock, of a DN700 mm (28″) cast iron water pressure pipe – the work was split in two section, each one 80 m (265 ft) long. The borehole diameter was 800 mm (32″). A very challenging job for the extreme hardness and abrasivity of the rock. The water pressure pipe is part of a mini hydro-power plant in the Alps (Italy).
INSTALLATION IN VERY HARD AND ABRASIVE ROCK OF A DN700 CAST IRON WATER PRESSURE PIPE