The location of a decline shaft portal can have far reaching implications if the geotechnical conditions are not suited for safe and cost effective excavation. Ideally the portal should be positioned in an area where the excavation requires minimal support ...

Installation of support in known poor ground intersections during reaming operations requires rapid access to stabilize the shaft wall and thus to prevent the loss of the shaft through scaling. This is especially relevant to shafts of long dimension where ...

<p>Shield TBM tunneling method along with other mechanized method is one of the preferred ways to make tunnel, especially for long tunnel with unfavorable ground condition. Shield method is well known to be effective and safe to make tunnel on shallow and ...