Page 197 - Urban Construction Project Management

152 Chapter Six
Exhibit 6-31
Fancy urban
bridge section.

material that is difficult to penetrate. Gates are provided for access of authorized trucks
and personnel. Guards are posted at the gates to check everyone’s identification. See
Chapter 11 for additional security information.

UNDERPINNING AND SHORING

In the urban environment, there is a lack of available land on which to construct new
structures. Thus, older buildings are torn down to make way for new structures. When
this occurs, older buildings surround the new building’s site. The new building’s foot-
ings and basement excavation may extend below the footings and perimeter walls of
the older buildings. When this occurs, the CM/GC must analyze the conditions that
exist and make sure that the older surrounding buildings will remain stable during the
excavation of the new building. This may require the temporary support of the older
buildings’ footings or the placement of a wall around the new site that will support
any load emanating from the older buildings’ footings. Whichever stabilization
process is selected, the CM/GC needs to review the foundation plans of the surround-
ing buildings. If the plans are not available, then other sources must be sought out.
The public library, local building department, and historical societies are good sources
of information.

If no documents are available, then bore scopes or test pits may have to be dug around
where the existing footings are located. This must be done with care so that the existing
footings are not disturbed. The owner’s design team and the CM/GC and a specialist
subcontractor should be brought in to review the conditions. Recommendations will
then be made as to which method should be employed with associated cost and