TOMAS - Cut and cover tunnel technology

The TOMAS Surface Tunneling technology is based on three innovations: 1. Building a semi circular tunnel from the surface in soils with high water table without draining or pumping out the sub-surface water. 2. Removing the soil mixed with water within a half round shield with standard cutter dredging technology adapted for this application. 3. Using standard segmented tunneling sections to shape the tunnel, but fixing these segments with post-tensioning under a continuous precast or cast on site concrete beam fixed and supported or held by rakes of piles. Benefits of this technology are: Short construction time because of fast building (50-80 mtrs/day) Low investment cost Limited construction space required No ground dewatering required Soil removal by dredging is the cheapest way of moving soil Material transport can be done through finished tunnel Minimum impact on the environment Use is made of well-known technologies Innovative construction method with international potential Current contact for technology licensing: Ing. Jaap H. Ketel, NEDLAND BV 3831 PB LEUSDEN The Netherlands Tel. +31.33.43 43 500 Fax. +31.33.43 43 501 Mob. +31.6.532 61 771