When the installation requires the utilization of existing foundations and
completely new foundations for certain portions of the chamber, then the
foundations must be evaluated differently. Essentially, the existing
foundations must be evaluated as outlined in the two steps above but the new
foundations must be completely evaluated in accordance with the criteria
outlined in Section 3.
STRUCTURAL SUPPORTS. The evaluation or design of the structural support
system is essentially the same whether the hyperbaric chamber is installed in
an existing building or is completely new construction. Design parameters
such as the strength capacity of the individual members and of the entire
framework, vertical deflection, lateral displacement, vibration response, and
fatigue strength must be evaluated in either case. The relationship between
the old structure loading and the new loading resulting from the hyperbaric
chamber must be compared and the necessary modifications to the framework
designed. The following design parameters listed in Section 5 for concrete
structures may or may not be of importance depending primarily upon the age
of the existing structure.
Concrete drying shrinkage effects and creep effects may be of
significance if the existing structural framework is relatively new.
However, if the framework is at least a year old these parameters, which are
peculiar to reinforced concrete, will probably have nearly reached a point of
stability. New loading, in excess of the loading to which the building was
originally subjected, will contribute to additional creep deflection however
and must be evaluated accordingly.
Similarly, in the case of prestressed concrete structures, the
elastic shortening and camber in the prestressed members will probably have
reached a point of stability if the structure is at least a year old. When
the installation of the hyperbaric chamber results in an increase or decrease
in total load on members of this type, then additional creep deflection or
camber may occur. Evaluation of these considerations are the same as
discussed in Section 4.