Tunnel Design & Specialities

Metro tunnel, 3,950 ft (1200 m) long with a section of approx. 660 sqft (62 m²). Overburden varied from 10 - 15 ft (3 - 5 m), reinforced concrete slab 2 - 4 ft thick.

New subway station platform access shaft. Connection from main ticket hall to underlying (bi-secting) platform cross adit (cast iron liner breakout). The design accommodates difficult existing station (spatial) encroachments by utilizing an elliptical shape with changes in size, axis and shape (from 3m to 6.5m).

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

A modern closed motorway 680 km long following an alignment running across Epirus and Northern Greece from Lgoumenitsa to Evros. DSC provided design review services on three twin bore two lane highway tunnels, total length 1.26km (each bore), cross section 106m2 approx. Tunnel supported by rock bolts and shotcrete with inner reinforced concrete lining. Design check included seismic and explosion loading cases.

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).

Provided tunnel expert advice during the excavation and support of an 18 ft diameter 5,500 ft long TBM driven tunnel. Support Type A (80%) with rock bolts and Type B (20%) with ring steel and lagging. Final lining with rein-forced cast-in-place concrete.

Tunnel widening from a 14 ft (4.3 m) to 29 ft (8.8 m) springline diameter section.

2 ventilation tunnels: 32 m² (344 sqft), 2 enlarged ventilation tunnels: 38 m² (409 sqft), 2 drop shafts: 75 m² (807 sqft), 1 horizontal and inclined emergency intervention tunnel: 19 m² (205 sqft), 1 horizontal cross passage chamber: 31 m² (334 sqft) with 4 cross adits underlining the London - Tilbury railway lines.

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.

NATM running tunnel connecting Convention Center station with surface to be constructed beneath historic downtown structures as part of existing LRT system expansion. Provided initial design package, including detailed cost estimate. Tunnel Length: ~446'* Cross Section: 41'-4" x 26'-11"; 895.24 ft^3 *Including widening zone for track cross-over.