For years open cut excavation has remained the primary method of utility installation across the world. The technical complexity and high capital costs associated with specialized tunneling equipment primarily limited tunneling efforts to large diameter transportation projects and mining efforts. Recent advances in trenchless methods have shown trenchless techniques, such as horizontal directional drilling and micro-tunneling, to be economically advantageous to traditional open cut methods. Risks associated with open cut utility installation have traditionally been considered easier to manage than those associated with trenchless options. Open cut operations are easier to adapt to unanticipated subsurface conditions and the industry’s experience with traditional bypass, cut and repair of crossing and conflicting utilities is well established. Trenchless methods however, require additional subsurface exploration and geotechnical monitoring to mitigate risks associated with utility/structure settlement, soil blow out, clogging of spoil return lines, unanticipated subsurface conditions and the avoidance of unpassable obstructions.
展开▼
