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Paul Raiford,
Branch Manager – Structural Preservation Systems
Mechanical Draft Cooling Towers are critical Fixed Assets that
need to be maintained and remain in service in order to cool various plant
operations and systems. Essentially,
the Cooling Tower Basin in mechanical draft technology
serves a two-fold purpose, one as containment for the cooling water and two
as the foundation for supporting overlying “fill” structures. Almost all of these Basin Structures are
constructed of conventionally reinforced concrete, either partially or
totally placed below grade. Their
service environment subjects them to various aggressive deterioration
mechanisms including embedded metal corrosion, original construction defects,
environmental degradation (i.e., freeze-thaw, algal growth, etc.) as well as
chemical attack resulting in erosion and structural section loss. Since these structures contain process
water and function as support foundations, the existing condition of these
structures should be evaluated regularly and repairs performed should
conditions warrant, on a timely basis.
Evaluation techniques exist, both Non-Destructive (NDT)
and Semi-Destructive Testing (SDT),
that can serve as tools in assessing in-situ conditions, either on or
off-line. Additionally, the Paper will
highlight Case Histories of Cooling Tower Basin Evaluations and subsequent
Repair Program implementation.
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