fi
— À SEC ENS
200
1.00
0.00
deformations
-200 -100
Fig.4. Axonometric view of shell deformation in development.
surface is completely smooth, gunited or painted, or
in case of investigation of deformation alterations
in time. Determination precision of geometric
imperfection alteration in nodes of finite element
net , on the base of external surface numerical
models, curried out in comparable measurement cycles,
can be too small as necessary for univocal evaluation
of cooling tower shell stability and strength.
4. CONCLUSION
Choice of one of photogrammetric methods for
investigations of real shape of hyperbolic cooling
tower external surface depends before all on
signalling and identification possibilities of
observation and control points on the cooling tower
surface. In case of existence of such possibilities,
the more suitable method is the stereophotogrammetric
one, which also has more possibilities of easy
further processing by means of existing computer
graphic programs.
In case of cooling towers without possibility of
signalling of observation points and control points,
and also in investigations of shell deformation
alterations, more suitable can prove the
monophotogrammetric method. The final choice of the
method depend also on possession of photogrammetric
devices and on possibility of photogrammetric devices
and on possibility of control over adequate
computational and graphical programs which permit to
determine required values necessary to evaluate
stability and strength of cooling tower.
5. LITERATURE
Chauvel, D., Bozett, P., Balvin, M., 1990. Long Term
Development of Cooling Tower Shells Backed by EDF. 7.
Symp. IAHR, Leningrad.
Golczyk, M., 1989. Technical Analysis of Causes and
Consequences of Damages and Collapses of Hyperbolic
Cooling. Tower Shells. Conference on "Durability
Problems of Reinforced Concrete Cooling Towers".
Wrocl aw-Castle Czocha.
Katowski, 0.,1990. Instruments and Systems for the
332
Surveillance of Man-Made Structures and Areas Subject
to Geophysical Movement. Civil Engineering Surveyor,
pp. 23-23.
Mierzwa, W., 1991. Photogrammetric Determination of
the Cooling Tower Shape Using for Results
Presentation Computer Graphic Software. Symp. Cooling
Towers-Effective Systems of Protection and Repair,
Jelenia Góra.
Owczarzy, J., 1991. Geometric Imperfections of
Hyperbolic Cooling Tower Shells. Symp. Cooling
Towers-Effective Systems of Protection and Repair,
Jelenia Géra, pp.77-82.
Owczarzy, J., 1989. Collapses of Reinforced Concrete
Hyperbolic Cooling Towers. Conference on "Durability
Problems of Reinforced Concrete Cooling Towers”.
Wroclaw-Castle Czocha, pp.101-108.
Report of the Committee of Inquiry into Collapse of
Cooling Towers at Ferrybridge. Central Electricity
Generating Board, 1966.
Wozniak J., 1988. Determining Deformation of Cooling
Tower Surface. Congress ISPRS, Kyoto.