The Dugway Storage Tunnel project (DST) is one component of a program being implemented by the Northeast Ohio Regional Sewer District (NEORSD) to improve the control of combined sewer overflows on the east side of the Greater Cleveland service area. The project area is mainly residential, interspersed with commercial properties and parks.The tunnel alignment is approximately 2.8 miles long, excavated with single shield hard rock TBM 27 ft diameter. The finished internal tunnel diameter is 24 ft. Depths to tunnel invert generally range from 180 to 230 ft below ground surface. The project will have a total of six shaft with internal lined diameter between 16 to 50 ft.Adit connections between shafts and tunnel will be excavated with conventional method.Successful Case of Groundwater Freezing at the Shaft DST1.

Lake Mead Intake No. 3 - Design-Build Project. Work of the Project includes a 600-foot deep access shaft with 30-foot diameter, excavated by drill and blast and lined with cast-in-place top-down concrete. Work also includes 15,300-feet of 20-foot I.D. tunnel under Lake Mead excavated by Herrenknecht hybrid TBM with diameter of 23.5 feet in mudstone, sandstone, and basalt. TBM is designed for operation under 17-bars of pressure and capable of operating in either open or closed pressurized mode. Spoil removal is by slurry system or continuous belt conveyor. Tunnel is supported by one-pass precast segmental lining with universal ring. Program for high pressure hyperbaric interventions was developed for maintenance of the TBM at all possible pressures and with the possibility of saturation interventions. Work also includes underwater excavation in 350-feet of water and construction and erection of underwater Intake Structure with integrated TBM docking station, and other ancillary work.Recognition of the Project:2016 Outstanding Civil Engineering Achievement Award, America Society of Civil Engineering (ASCE) Finalist.2016 Tunnel Achievement Award for Project Excellence (Tunnel Business Magazine).2015 Global Tunneling Project of the Year (over $500 Million) Tunneling & Underground Space Awards.

The Barcelona Metro Line 9 Project consisted of the construction of tunnel 150,000 ft long with 5 shielded tunnel boring machines (two EPB Herrenknecht of 31 ft diameters, two EPB Herrenknecht of 40 ft diameter and one Dual Mixshield tunnel boring machine NFM-Wirth of 40 ft diameter). The cutterhead interventions were executed systematically in hyperbaric conditions. The excavation was done through very heterogeneous geological conditions, faults areas, with high groundwater inflows and under very dense urban area, requiring special attention to mitigation of surface settlement, with building and infrastructure movements controlled by an elaborate monitoring plan. The tunnel was supported by precast segmental lining with universal ring. The project included the excavation of 52 stations, shafts of 87 ft internal diameter, between 83 ft and 267 ft depth of which 20 will be interchange stations accessible to another transit system. The excavation of the shafts was executed with mechanical methods and with drill and blast depending on the geological ground conditions. The project included the mechanical-electrical installations inside of the tunnel and stations and also the station’s architectural features.

The Project consisted of the excavation of an emergency evacuation tunnel parallel to an existing roadway tunnel. The excavation was executed with a Wirth hard rock TBM with a diameter of 15 ft and the total length of the emergency tunnel was 12,300 ft. The tunnel was supported by shotcrete, wire mesh, rock bolts and steel ribs according to the different geological conditions encountered. The project included the excavation of 19 connections tunnels between the emergency tunnel and the roadway tunnel, one every 610 ft approx.

The Project consisted of the excavation of an emergency evacuation tunnel parallel to an existing roadway tunnel. The excavation was executed with a hard rock TBM with a diameter of 15 ft and the total length of the tunnel was 6,333 ft. The tunnel was supported by shotcrete, wire mesh, rock bolts and steel ribs. The project included the excavations of 6 connections tunnels between the emergency tunnel and the roadway tunnel, one every 900 ft.

The Acheloos Project consisted of the excavation of a main tunnel, 57,000 ft long with 22 ft diameter, driven using a open mode Wirth TBM; cast-in-place concrete lining; a water intake; a service tunnel 1,475 ft long excavated with drill and blast; a sluice gate shaft; a 470 ft deep surge shaft approximately 66 ft in diameter. Contract value: approx. $70M.

The Wanjiazhai Project consisted of the excavation of a main hydraulic free flow tunnel, 293,333 ft long with 14 ft ID, driven using 4 double shield TBMs. The tunnel was supported by precast hexagonal segment lining to form honeycomb shaped rings. Contract value: approx. $ 200M.

The Singkarak Project consisted of the excavation of a hydraulic pressure tunnel, 54,333 ft long excavated with drill and blast and with a open hard rock TBM manufactured by Robbins, 20 ft diameter. The tunnel was supported by shotcrete, wire mesh, rock bolts and steel ribs lined with cast in place reinforced concrete lining. The project also included the excavation of an underground Power House 84 ft X 150 ft X 330 ft, one gate shaft and one pressure shaft. Contract value: approx. $ 140 M.

The project consisted of the excavation of 10,000 ft of rail tunnel with drill and blast method and with a roadheader. The tunnel, with a large section of 1,291 ft2, was supported by shotcrete, wire mesh, rock bolts and steel ribs according to the different geological conditions encountered and finally with cast-in-place reinforced concrete lining. The tunnel passed under a dense urban area and infrastructure, with consolidation works in advance of excavation.