Gavin and Doherty Geosolutions (GDG) formed a Geohazard Team, which will apply its expertise worldwide to reduce geohazard risks and to overcome changing environmental conditions. Geohazards comprise geological conditions and environmental processes that create a risk or threat to infrastructure, the built environment and human life. These processes can occur over long timescales taking centuries to cause a noticeable impact or in other circumstances the processes can be rapid causing devastation overnight. Examples of geohazards include landslides, mudflows, karst sinkhole development and collapse features, the presence of shallow gas in the ground, coastal erosion, etc. Paul Doherty, managing director of GDG, noted that “geohazards are having an increasing impact on the world around us and can cause mass devastation if not treated with respect. We have built a team of experts in this area with a view to providing advice and consultancy to public bodies and private clients across the world. Our level of technical knowledge has been tailored to this field with a team of Ph.D.-qualified engineers, geologists, risk analysts, geomorphologists and various scientists providing a very high-level of expertise.” Recently, GDG were commissioned by the World Bank to undertake a landslide hazard and risk study for Guatemala, which has a history of ground instability in densely populated regions. The GDG team were selected for this mission due to its award-winning expertise in the mechanics of landslides and risk mapping. Colby Barrett, CEO of GeoStabilization Interna- tional, is being honored as one of the national “Top 20 Under 40” by ENR. This annual award recog- nizes industry leaders under the age of 40 who represent “the pinnacle of leadership skills, community service, work ethic and talent.” Liebherr Crane and Grab in Milan Liebherr’s new package for slurry wall applications comprising a duty cycle crawler crane and a hydraulic grab were presented at Intermat in Paris in April, and have been successfully performing work for the metro expansion in Milan. The interaction is optimized so that the work can be carried out quickly and precisely and with the utmost efficiency. The hydraulic slurry wall grab is modularly designed and has an extremely robust base body. As the names of the grabs imply, HSG 5-18 C and HSG 5-18 L, slurry walls with thicknesses between 500 mm (20 in) and 1,800 mm (71 in), respectively, can be installed. The term “C” (compact) represents the compact standard design, while the base body of the “L” (large) version is 2.5 m (8.2 ft) longer. The total height of the grab is 9.5 m (31 ft) and the high weight with low center of gravity provide for even better vertical positioning and are especially advantageous when installing larger dimensioned slurry walls. When working in difficult ground conditions, the execution of the work can be improved through increasing the dead weight of the grab with an additional weight of 7 tonne (7.7 ton). The heavy weight of the grab is viable due to the proven synchronization of the free-fall winches. The slurry wall package can be optimally adapted to the conditions on the jobsite and 124 • DEEP FOUNDATIONS • SEPT/OCT 2018 is highly efficient. Although part of the slurry wall package, the duty cycle crawler crane maintains its multifunctionality and can, for example, be quickly converted for chisel application or operation as a lifting crane. A video explaining the design and functions of the new slurry wall grab, HSG 5-18 C/L, can be found at https://www. youtube.com/watch?v=aL-PlTM28GE. Integrated Vertical Positioning A sensor can be optionally fitted onto the grab, which measures the vertical positioning in x, y and z directions. Through the full integration of the vertical assistant in the duty cycle crawler crane’s Liebherr control system, even greater precision can be achieved. Data is trans- ferred from the sensor to the control system via Bluetooth. The current verticality of the bite and any possible deviations are displayed on the monitor in the operator’s cab. Using Liebherr’s process data record- ing, PDE, all process data are electronically logged, displayed and recorded. Slurry Walls for the New Metro Line in Milan Opened in 1964, the Metropolitana di Milano is scheduled to be expanded by 2022, with the new line M4. The 15 km (9.3 mi) long route with 21 stations
