Site Supervision & CM, QA/QC

PVC membrane waterproofing for 150 ft (64 m) of Cut & Cover tunnel, an open cut station and 300 ft (91 m) of boat section. Waterproofing details for over 400 foundation piles and 380 conduit penetrations in groundwater were developed.

Approximately 14 m span twin track railway tunnel. Approximately 200m long. Using doorframe slab method.

2.5 km Dual Track Running Tunnels and two Stations with a maximum span of 16.2 m. Excavation of 60-65 m² running tunnel in combined top heading/bench with a subsequent invert excavation. Reinforcement consists of lattice griders and welded wire fabric for initial lining and welded wire fabric for final shotcrete lining.

Section T02 comprises 7716 of 6m inner diameter sewerage tunnel, 6 permanent access shafts and 3 lateral access tunnels connecting the access shafts with the sewerage

NATM Light Rail Station located 150 ft (46 m) beneath surface. Station complex includes central elevator/access shaft, concourse, opposing platform tunnels and cross passages. Platform Tunnel Section: 36 ft w x 31 ft h; Platform Tunnel Area: 925 sqft (86 m²); total Station Excavation Area: 63,000 sqft (5853 m²).

Main Shaft: 18 m (59 ft) dia., depth 30 m (98 ft); Inspection Shaft: 11m (36 ft) x 7 m (23 ft) elliptical, depth 10 m ; Ventilation tunnel: width: 6 m(20 ft) x height: 12 m (39 ft) elliptical.

3 shafts, 12 ft (3.7 m) ID, 40 ft (12 m) to 130 ft (40 m) deep with a sprayed concrete (fcu 25 N/mm²) shell, 6 inches (150 mm) thick. Breakout into a combined sewer line at the bottom of the shaft.

The brick lined tunnel constructed by Mark Brunel between 1825 and 1841 was the first to be bored underwater using a shield and comprised of a twin arch tunnel, 375m in length, with cross passages every 5.5m. The new lining has been designed to minimizethe removal of existing structural brickwork and has a similar shape with cross passages to match the original tunnel. The reinforced concrete/shotcrete lining includes steel fibers to increase the strength and durability of the lining. A waterproof membrane has been installed around both tunnels and the cross passages between the structural brickwork and the new concrete lining.

Temporary shotcrete lining design of running tunnels, step plate junction, temporary works access tunnels, shafts, platform and concourse tunnels and ventilation tunnels. Permanent lining design, reinforced concrete and steel fibre reinforced shotcrete.

The Eisenhow tunnel is the highest highway tunnel in the world with an average elevation of 11,100ft. As a result, it is subject to sever weather conditions throughout the year. Cross Sections:(2) 48 ft. width x 40 ft. height Length: 8,941 ft. (7,789 ft. mined in rock) CDOT submitted a claim against the manufacturer of pre-fabricated till wall panels that failed due to excessive water/ice build-up. DSC provided on-site inspection of both tunnels then produced a comprehensive technical report on remedial solutions to counter water/ice inflows within tunnels