Underwater inspection of bridges

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Underwater inspection of bridge
by Kokodeev A.V., Ovchinnikov I.G
History
15 December 1967 - the accident at the
Silver Bridge, USA
Silver Bridge
 Location - West Virginia, across the Ohio river
 Field of application - car
 Total length - 443 m, the number of spans -3
 The type of construction is suspension bridge, material - steel
 Open - 1928, close - 1967
The main causes of the collapse
The increased load
from the increased
traffic flow.
Consequently, the
deformation of one
of the suspension
rod.
Material fatigue and
abundant corrosion
of individual
elements of the
bridge
Consequences
1968 - the initiative of the US Congress
about the introduction of new state
standards inspection of the condition of
bridges
Requirements
Every state should carry out periodic inspections inspections
on bridges, in their territory, with a maximum interval
between inspections in 24 months.
Inspectors must have the necessary qualifications on this
issue.
Should be developed and training of inspectors.
Schoharie Creek Bridge Collapse
5 April 1987 - the destruction of the bridge
Schohari Creek, new York, USA
The main causes of the collapse
Abnormally large amount
of precipitation, and rich
of snowmelt resulted to
extensive scour.
Inspections and
maintenance of the
bridge were not
conducted properly,
certain errors designers.
Underwater inspection of bridges
1
2
3
Provision of necessary state supports
(foundations, piers, pylons) for safety operation
of the bridge
Detection of various defects of underwater bridge
elements
Prevent any possible damage of structural elements
of constructions with the help of timely action
What check?
Cavity (cracks) in stone / concrete masonry
Detection of weathering of masonry
Damaged / missing elements of masonry
Checking the condition of joints and seams
What check?
Assessment to exposure of reinforcement and rebar
Traces of rust, chips, abrasive wear, crushing in concrete
elements
Checking the status of the steel constructions (pipes, steel
caisson and screw piles, steel caissons)
Assessment of ground deformation in support parts
bridge construction
Examples of failures and defects of the bridges
elements
Diving as a way of underwater inspections
The types of diving works
Scuba diving: the diver is equipped with
autonomous device for air supply
The types of diving works
If necessary, a long and detailed inspection, apply
such technologies diving, in which the diver is
connected with a special cable with equipment on
the surface.
Norm and safety for divers
 The minimum age diver 18 years of age, maximum age of 45 years
 Fitness by doctor in last six months
 Good physical condition, ability to withstand stress
 Free from cardiac and ear problem
 Not addicted to alcohol and excess smoking
 Going special tests to work at the depth
 Knowledge of special signals when diving
 Ability to work in zero visibility conditions
Type of underwater inspection
 Sonar (SOund Navigational And Ranging - sound
navigation and ranging) uses sent and reflected
sound waves to detect underwater objects and
distance measurement.
 ROV devices (remotely operated vehicle).
Relevant for large depth of research, or when
environmental conditions when it is impossible to
adequately conduct the underwater inspection of
the bridge.
ROV devices
Teamwork divers and ROV
Rov’s technologies in some cases can apply well in advance
of diving divers to collect information on defects structures,
the formation of scour, acting on the support, and also about
the clusters of construction and other debris, which will facilitate
and ensure the safety of the divers. ROV’s devices can serve as
a navigator, guiding divers to certain areas.
Example of application
 May 2008, floods in the Midwest, USA. Photo of the
Cedar Rapids, Iowa.
The impact of the floods on the bridges
With the rise of water level in the
reservoir water penetrates through
the gaps between elements of the
walls and saturates soil backfill.
Increases its disposal and may lead
to irreversible deformation
structures.
At fluctuations of water level in the
reservoir occurs alternate wetting and
drying of the surface of the elements
of the bridge.
Leads to the development of the
corrosion processes.
Example of application
Images of underwater parts of the supports,
received with the use of sonar
«Kongberg Mesotech».
The list of methods and devices for underwater
inspections
Sounding methods - to control scour
Magnetic particle research – to detection of cracks on the
surface of parts of supports produced in the framework
Magnetic recognizer rebar– to determine rebar location
Ultrasound system- to the check uniformity of filling and
compaction of the concrete
Radiography – for detection of internal defects
Procedure for defects elimination in the
underwater part of the bridges elements
1) Initial inspection, filming future work places
2) Cleaning and surface preparation processed
elements of bridge support
Stages
3) Evaluation of terms and cost of works
4) Getting work start, formwork/fixing worksheets
5) Micro-concreting and finish the job
Conclusion
 Systematic and scientific aimed underwater exploration is very
important for the safe operation and management of bridge
construction.
 A considerable number of collapses and accidents occurring on
bridges can be avoided by timely conducting underwater
inspection and examinations.
 Having familiarized with the experience of foreign scientists in
the solution of these questions our specialists can speed up the
process of development of the domestic technology of
underwater bridges inspection.
REFERENCES
1.
Podvodnoe obsledovanie transportnyh sooruzhenij / V.V. Sokolov, P.P., Nikitin P.P. Izd-vo «Transport», 1970. 152 s.
2.
Obsledovanie, remont i usilenie osnovaniy I fundamentov transportnih sooruzheniy I.G. Ovchinnikov, A.A.
Shein, A.A. Piskunov, uchebnoe posobie, Kazan, izd-vo KGASA, 2005. -300s.
3.
K.Simon Mohd. Bakhsh, A.Raj Kumar Underwater inspection of bridges illustrated with case study, 2010, P. 35
4.
Terence M. Browne, P.E.; Thomas J. Collins, Michael J. Garlich, John E. O’Leary, Daniel G. Stromberg,
Katherine C. Heringhaus Underwater Bridge Inspection Collins Engineers, Inc. // llinois, 2010, P. 224.
5.
Daniel G. Stromberg, Collins Engineers, Inc New advances in underwater inspection technologies for railway
bridges over water // Chicago, Illinois, P. 29
6.
Leshko Brian J. Revised National Bridge Inspection Standards (NBIS) // Structure magazine, December 14th,
2004 USA P. 45-47
7.
Site of U.S. Department of Ttansportation. Federal Highway Administration.- Electronic data.- Washington
,2014. -http://www.fhwa.dot.gov/
8.
Wikipedia.- Electronic data.- 2014.-http://en.wikipedia.org
9.
Site of the Recorder magazine.- Electronic data. ttp://www.recordernews.com/news/04052012_bridgetimeline.
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