The construction of a diaphragm wall at the Puclaro Dam is an impressive example which proves the technical and economic feasibility of the diaphragm walling technology for forming a watertight cut-off wall even in very difficult soil conditions. On this project Bauer was contracted by the Ministry of Public Works to install a 60 m deep positive cut-off wall, with a surface of 16,850 m2 and a thickness of 800 mm.
Based on subsurface geology consisting of alluvial sand and gravels with boulders, and a rock socket in sandstone and andesite (180 MN/m2), Bauer mobilized a BC 30 trench cutter (40 tons), mounted on a 80 ton hydraulic crawler crane and equipped with tungsten carbide tipped teeth and roller bit cutter wheels for 800 and 1200 mm.
Additionally, Bauer used 2 GB 30 carrier units with a 20 to free-fall winch for hydraulic grabs, and 1 GB 30 carrier unit with a 20 to freefall winch for heavy chisels; 4 hydraulic grabs DHG with 6 jaw sets, and two desanding plants with capacity ranging from 200 – 500 m3/h .
This amount of equipment enabled an average wall productivity output of 1200 – 1500 m2.