Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter.
Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.
Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.
OCR for page 30
30
INSPECTION TYPES--FOREIGN ROAD AGENCIES Detached objects; for example, fragments of concrete,
railing segments, and goods that have fallen off lorries;
Denmark
Function of drainage systems;
Conditions of road surface; and
The Danish Road Directorate identifies eight types of bridge
Winter conditions; accumulation of ice and snow.
inspections (Table 42).
· Inventory inspections are made for new bridges, after Daily inspections are not recorded in the bridge database.
major projects on bridges, and in general after each sig-
nificant construction or repair event in the service life of · Routine inspections are done once a year by the mainte-
a bridge. nance foreman or the bridge engineer for the road man-
· Daily inspections are made by road maintenance crews. agement authority. The inspector must stop and view the
Each day, the highway road patrol performs a drive-by bridge from the deck and from below. The inspector ver-
inspection of all national roads, noting distress in ifies that recommended cleaning and routine mainte-
bridges, pavements, and all other road facilities. Crews nance have been done and makes further recommenda-
observe each bridge in all weather conditions and tions for cleaning and maintenance for the next year.
develop a thorough familiarity with each structure and Maintenance work that is not complicated and of modest
its basic systems. Daily inspections note: cost (around $20,000 U.S. maximum) is programmed
Failure of load-bearing components; through Danbro, the Danish bridge management system,
Impact damage; and done by maintenance contractors. Maintenance con-
Washing away of slopes, shoulders, etc.; tractors are supervised by the Directorate's regional
Vandalism on slope facings, railings, traffic signals, bridge inspector. Routine inspection notes:
lights, etc.; Stoppage of drainage systems;
TABLE 42
TYPES OF BRIDGE INSPECTIONS--DENMARK
Inspection
Type Description Interval Inspector
Inventory Collect bridge data and baseline At new construction, and Bridge inspector
conditions after every major repair
project
Dailya Cursory examination noting Daily Road
failure, damage, debris, etc. maintenance
crewb
Routine-- Planning and checking routine Annually Consultant
Extended cleaning and maintenance bridge inspector
Inspectors stop and view the
structure from the top and
bottom
Damage, if any, is noted.
Reports from Reports of: In response to user report
Users impact damage
vandalism
debris on bridge or road
erosion damage
Principal Thorough and systematic visual 6 years or lessc Directorate
inspection of all the components bridge inspector
of the bridge
Special Collection of more detailed In response to Consultant
information for decisions on recommendation from bridge inspector
maintenance actions routine inspection
Economic Preparation for major repair In advance of project Consultant
Special project for a bridge selection and development bridge inspector
Inspection Development and comparison of
remedial strategies
Technical Damage investigations In response to extreme event, Consultant
Special Special investigations or suspect capacity bridge inspector
Inspection Load-carrying capacity evaluations
a
Not a formal part of the Directorate bridge inspection program.
b
Specially trained personnel. Currently provided by contractors, but Directorate personnel were scheduled
to take over this work in 2007.
cApproximately 5% of Directorate bridges have Principal inspections at intervals of less than 6 years.
OCR for page 31
31
Grit and dirt, especially along edge-beams, gutters, the formation and updating of bridge deterioration
low points, expansion joints, etc.; models. Basic inspections are performed by degreed
Unwanted vegetation; engineers who are certified bridge inspectors.
Erosion on slopes, washing away of foundations, · Special inspections collect complete, detailed informa-
hindrances, and deposits in watercourses; tion in preparation for repair projects. Special inspec-
Settlements at abutments and around manholes; and tions are usually done by certified inspectors who are
A need for preventive maintenance (e.g., surface pro- degreed engineers and have experience with the testing
tection of concrete). methods that may be needed at particular structures.
· Reports from highway users can require special visits to · Underwater (dive) inspections are done by certified in-
bridges. Often these reports deal with impact damage, spectors with special training. Bridge components are
vandalism, debris on the road, and erosion damage. inspected both visually and by touch.
· Principal inspections are thorough visual inspections of · Intensified monitoring, a kind of interim inspection, is
all components. The inspector assigns condition ratings to performed on selected components and may be done by
all components. Principal inspections are usually per- bridge inspectors, engineers, or road foremen depend-
formed at 6-year intervals, but may be undertaken at ing on the nature of the monitoring program.
shorter intervals. The inspector notes damage, reports the
apparent causes of damage, and evaluates the risk to
users. The inspectors recommend the interval to the next For long-span bridges in good condition, general inspec-
Principal inspection and may recommend additional spe- tions are performed at 8-year intervals. The inspection of a
cial inspections. The interval to the next inspection de- long-span bridge is a complex effort that requires lane clo-
pends on the bridge age, average daily traffic, location, sures and lift equipment. Long-span bridges usually have
existing conditions, and special features. Recommenda- high traffic volume. Inspections are intentionally more
tions for maintenance and repair are made, with the in- intense at large bridges, with the increased scrutiny permit-
spector estimating the cost for each recommendation and ting the longer inspection interval.
indicating when the recommendation should be com-
pleted (within 1 year, 2 years, or as many as 11 years into For most bridges, inspection intervals are determined by
the future). two factors. One is the bridge; inspection intervals are con-
· Special inspections collect more detailed information sistent with the condition of each bridge. The other is logis-
about specific conditions at bridges. tics; bridges in remote areas are inspected when personnel
· Economic special inspections provide information are on hand; therefore, inspection intervals may be somewhat
needed for selection of repair strategy and development longer or shorter than intended.
of plans.
· Technical special inspections are detailed investiga-
tions of damage seeking causes of damage and evaluat- France
ing the effect of damage on load capacity.
France has four types of routine inspections: routine visit,
annual inspection, IQOA (Image de la qualité des Ouvrages
Finland
d'Art: Image of the Quality of Bridges, Walls, and Tunnels)
Finland defines seven types of routine bridge inspection (see evaluation, and detailed inspection (Table 44). Routine
Table 43). visits are made by road agents during their patrols. Annual
inspections are cursory examinations intended to discover
· Acceptance inspections are done to add or modify bridge new, significant defects in structures, and to program
inventory data (the Finnish term is "registry data"). Ac- routine maintenance. IQOA evaluations occur every three
ceptance inspections occur for newly constructed years and are more complete visual examinations of struc-
bridges and after major repair or modification projects. tures to establish the condition of bridges in IQOA classes.
· Annual inspections are performed by road maintenance Detailed inspections occur at intervals ranging from 3 to 9
foremen, or consultants hired by road foremen, and years, depending on bridge condition, and are thorough
seek conditions that are a threat to safety. visual examinations of bridges noting all defects. The de-
· General inspections are thorough visual inspections tailed inspection is a "blank slate" examination. The annual
performed every 5 years for most bridges, and every 8 inspection, in contrast, is a check of defects known to exist
years for large bridges. All bridge components are at the structure.
assigned condition ratings, and inspection data are
entered in the bridge registry. General inspections are Annual inspections and IQOA inspections often require
done by certified bridge inspectors. about one-half day of work for the inspection team. Detailed
· Basic inspections are similar to General inspections, but inspections require additional time and usually require
are performed on a select population of 125 bridges access using lane closures, lift equipment, etc. The detailed
called reference bridges. Data from basic inspections inspection is a hands-on inspection. This is mandatory; the
and the accompanying materials tests are the basis of inspector must be able to touch each component.
OCR for page 32
32
TABLE 43
TYPES OF BRIDGE INSPECTIONS--FINLAND
Inspection
Type Description Interval Inspector
Acceptance Collect data for bridge registry After construction or District bridge engineer
repair work
Inspection of all components at Bridge engineer and
arms length designer
First general inspection of a large
bridge
Annual Cursory inspection for safety 1 year Road foreman or
maintenance consultant
General Inspection of all components at 4 to 8 years (usually 5 Certified bridge
arms-length years) inspector
Results are stored in the Bridge
Registry by the inspectors
themselves.
Inspection of all components at Large waterway bridges Certified inspector with
arms-length 8 years engineering degree
NDT methods are used when
necessary
Results are stored in the Bridge
Registry by the inspectors
themselves.
Basic For reference bridge group 5 years Certified inspector with
engineering degree
Inspection of all components
Includes material sampling and
testing to improve deterioration
models
Special Methods vary with needs of For planning and Certified inspector with
project development of repair engineering degree
projects
Machinery of movable bridges; 1 year Specialist
includes annual maintenance
Suspension cables, stay cables 15 years Certified bridge
inspection, specialist in
cables
Underwater Inspection by diving; visual and 5 years Certified inspectors with
touch inspection of components special training
Intensified More frequent inspection Due to poor or weakened
Monitoring condition
Germany Minor tests are done three years after each major test.
Minor tests use findings of the previous major test and focus
Germany performs bridge inspections at two levels called on known damage and defects. Access equipment is not used
Major Test and Minor Test (15) (Table 45). Major tests are in a Minor test, but the level of effort is expanded as necessary
arms-length (DIN wording is "touching-distance") inspec- for the conditions that are observed. Tests of electrical and me-
tions of all elements with access to all parts. This entails chanical equipment, such as ventilation systems, are required
opening access doors and covers, using lift equipment, per- by statute.
forming underwater inspection, and inspecting the riverbed.
Lane closures are used, if necessary, but use is limited by the All highway structures are visited twice a year for safety.
large traffic volume on most federal roads. Major tests are Viewing is from the ground level as well as the traffic level.
performed at acceptance of construction, near the end of the Germany performs ad hoc inspections after significant events
guarantee period, and every six years during service life. such as storms or floods.
OCR for page 33
33
TABLE 44
TYPES OF BRIDGE INSPECTIONS--FRANCE
Inspection
Type Interval Performed by Description
Routine Visit Frequent Road maintenance agents Drive-by inspection
employed by DDE
Annual 1 year Road maintenance agents Cursory examination during visit to
employed by DDE bridge
IQOA 3 years Inspection agent sometimes Visual verification of conditions
with certified inspector focusing on known defects
Detailed 9 years Certified inspector Robust bridges. Arms-length visual
examination of all components
and noting all defects
6 years Certified inspector Normal bridges. Arms-length visual
examination of all components
and noting all defects
3 years Certified inspector Ill bridges. Arms-length visual
examination of all components
and noting all defects
1 year Certified inspector Very ill bridges. Arms-length visual
examination of all components
and noting all defects
Underwater 6 years Certified inspector Diver making arms-length touch
and visual inspection
DDE = Direction Départementale de líEq uipment.
The names of inspection types are used a bit differently in the · Installation of fixed ladders;
German preservation and maintenance guide (15) (Table 46). · Lighting, both exterior and interior; and
· Room for jacking points at abutments.
German structural design practice requires explicit con-
sideration of access for inspection. Germany's guide to de-
sign for monitoring, inspection, and maintenance (16) directs Norway
designers to consider:
The Norwegian Public Roads Administration (17) identifies
three classes and seven types of inspection (Table 47).
· Visibility of parts;
· Internal clearances in boxes; · Acceptance inspections are performed for new con-
· Interior ventilation; struction and after major repair projects.
TABLE 45
TYPES OF BRIDGE INSPECTIONS--GERMANY
Inspection
Type Description Interval Performed by
Major Test Arms-length inspection of all components; 6 years Bridge inspector
uses access equipment and includes
underwater inspection
Acceptance Major test After new construction
or major rehabilitation
Guarantee Major test Near the end of the
guarantee period
Minor Test Verification of current state of known 3 years after Major test Bridge inspector
damage and defects
Superficial Cursory inspection for safety 3 months Road
maintenance
crew
Ad Hoc After significant events, such as storms, N/A Depends on
floods, etc.; also for known, severe situation
damage.
Systems Inspection of electrical or mechanical As required by
systems regulation
N/A = not applicable.
OCR for page 34
34
TABLE 46
INSPECTION DESIGNATIONS--GERMANY
Designation Description
H1 Main inspection before acceptance
H2 Main inspection before the expiration of the claims deadline for defects
H Main inspection
E Simple inspection
S1S9 Special inspections (inspection owing to particular reasons)
Warranty inspections are performed near the end of part of quick surveys conducted after accidents, floods,
the warranty period for construction or repairs. cyclones, or other extreme events.
· Routine
General inspections every 1 or 2 years, and Principal inspections are conducted every 5 to 6 years by
Major inspections every 5 to 10 years. Structural inspectors who are experienced in bridge design, maintenance,
cables are inspected every 5 years. or rehabilitation. Principal inspections are thorough examina-
· Additional Special inspections for known damage or tions of bridges that record all defects. A principal inspection
after extreme events are performed as needed. produces a full inspection report with photographs. The 5-year
interval for principal inspections matches SANRAL's 5-year
Norway specifies the field measurements and materials tests programming cycle for bridge repairs.
that are part of each type of inspection (Table 48). General
inspections require few measurements and no materials testing. Verification inspections are part of SANRAL's QA pro-
Major inspections require many measurements and tests. gram. Each year some bridges are selected and their condi-
tions are verified by a senior bridge inspector.
South Africa Two event-related inspections pertain to repair projects.
(1) The project-level inspection is a directed examination of
South African practice includes three types of routine inspec- a bridge to collect data needed for the preparation of contract
tions: Monitoring, Principal, and Verification (Table 49). Mon- documents for a repair project; and (2) an acceptance inspec-
itoring inspections are performed by maintenance personnel tion is made after repairs are complete.
and occur at frequent but irregular intervals. Maintenance per-
sonnel report problems, if any, but do not otherwise report that Condition data from principal inspections are stored in the
specific bridges have been visited. Monitoring inspections are bridge database. Monitoring inspections do not produce con-
part of routine maintenance surveys for road sections and also dition ratings.
TABLE 47
TYPES OF BRIDGE INSPECTIONS--NORWAY
Class Type Description
First Acceptance Performed for new construction and after major repair projects
inspection Note deficiencies and damage
Identify sources of deterioration that may be significant to maintenance
Warranty Performed near the end of the warranty period
inspection Verify that repairs required by acceptance inspection are complete
Note additional deficiencies and damage
Identify additional sources of deterioration that may be of significance to
maintenance
Routine General Check for any serious damage affecting the load capacity, traffic safety,
inspection future maintenance, or environment/aesthetics
Major Inspection of all components
inspection Determine needs for maintenance or repair
Estimate costs of maintenance or repair
Measurements and material sampling as needed
Major Inspection of cables, hangers, clamps and anchorage points
inspection-- Verify adequacy and function of cable systems
Cables Determine maintenance needs and costs
Major Dive inspection
inspection-- Inspect submerged components
Underwater Inspect the river bed
Determine maintenance needs and costs
Additional Special Diverse purposes:
inspection investigation of known damage
development of repair/rehabilitation projects
checking after extreme events
checking after problems at bridges of similar type
OCR for page 35
35
TABLE 48
REQUIREMENTS FOR TESTS--NORWAY
Major Major
Acceptance Warranty General Major Inspection Inspection Special
Inspection Inspection Inspection Inspection Cable Underwater Inspection
Measurements
Bearing elevations X X X X
Horizontal distances/displacement X X X X X
Thickness of wearing surfaces X X X X
Track wear X X X X
Evenness X
Sag X X X X
Recording bridge details X X X
Headroom X X X
Materials Investigations--Concrete
Rebar location and cover X X X
Depth of carbonization X X
Chloride content X X X X
Corrosion investigation (ECP) X
Structural analysis X
Inspection of bracing cables X
Cutting open the concrete to assess X
corrosion level
Materials Investigations--Steel
Check bolt torque X
Check rivets X
Check welds X
X-ray check X
Ultrasound check X
Magnetic powder check X
Fiber optics X
Ultrasound measurement of material X
thickness
Materials Investigations--Stone and
Wood
Humidity check (wood) X
Fungus and rot check (wood) X
Compressive strength X
Checking Surface Coating
Thickness of surface coating X X
(concrete)
Adhesive bonding between surface X X
coating and concrete
Thickness of surface coating (steel) X X
Adhesive bonding between surface X X
coating and steel
Condition of surface coating (wood) X X
TABLE 49
TYPES OF BRIDGE INSPECTIONS--SOUTH AFRICA
Inspection
Type Interval Performed by Description
Monitoring At least once each year, Maintenance personnel Quick look for new defects
usually more and status of known
frequently defects
Principal 5 years Inspectors experienced in bridge Full report with
design or maintenance photographs of defects
Verification ~60 bridges per year Senior bridge inspector QA effort to verify
accuracy of inspection
data
Project-level Before repair project Experienced bridge engineer Inspection to collect
employed by consulting information for contract
engineering firm documents
Acceptance After repair project Experienced bridge engineer Inspection of work during
employed by consulting and after contract
engineering firm
OCR for page 36
36
TABLE 50
TYPES OF BRIDGE INSPECTIONS--SWEDEN
Inspection
Type Interval Performed by Description
Regular Frequent Maintenance Quick visit to detect significant new conditions
contractor
Superficial 12 months Maintenance To verify that maintenance requirements are met
contractor
General 3 years SRA staff or Follow-up on damages detected at the last major
consultants inspection
Visual inspection of components
Major 6 years SRA staff or Arms-length, visual inspection of all components.
consultants Includes underwater inspection
Basis for recommendations for continuing maintenance
Special As needed Consultants Further investigation of defect or deterioration
mechanisms
May involve testing methods
Sweden In addition, SRA performs Special inspections of known
defects, suspected defects, and deterioration mechanisms, as
Sweden has four levels of routine inspections: Regular, needed. Special inspections will often involve testing meth-
Superficial, General, and Major (Table 50). Regular inspec- ods such as ultrasound, radiography, etc.
tions are frequent, quick visits to bridges to detect significant
new conditions. Such inspections are done by maintenance
contractors, and may occur once a day or once a month. Su- United Kingdom
perficial inspections are made once a year to verify that con-
tract maintenance requirements are being met. Superficial The U.K. Highways Agency identified five types of bridge in-
inspections are done by maintenance contractors. General spection: Acceptance, Superficial, General, Principal, and
inspections are made every three years by trained inspectors Special (Table 51). Acceptance inspections are performed for
from SRA staff or SRA consultants. General inspections new bridges, newly repaired bridges, and newly assigned
check on defects discovered in a previous Major inspection. responsibility; that is, at the start of a new maintenance con-
General inspections also examine electrical, hydraulic, or tract. Superficial inspections are frequent visits to bridges
other bridge equipment. Major inspections are made every made by the road maintenance contractor. Superficial
six years by trained inspectors from SRA staff or SRA con- inspections do not yield condition ratings. General inspec-
sultants. Major inspections are complete examinations tions are visual inspection of all parts of bridges. General in-
reporting all conditions and noting all defects in bridges, and spections are made every two years. No access equipment or
include underwater inspection. Major inspections are lane closures are used. Principal inspections occur every six
the basis for specification of requirements for continuing years and are thorough visual examinations of all parts
maintenance. of bridges, reporting all conditions and noting all defects.
TABLE 51
TYPES OF BRIDGE INSPECTIONS--UNITED KINGDOM
Inspection Performed
Type Interval by Description
Acceptance N/A When responsibility for the structure changes hands; i.e., on
completion of construction, when contracts for maintenance
change
Superficial Frequent Contractor The contractor staff is encouraged to be vigilant at all times
and report anything needing urgent attention, such as impact
damage to superstructure, bridge supports, flood damage,
expansion joints, etc.
General 2 years Contractor A visual inspection of all parts of the structure that can be
inspected without special access equipment
Principal 6 years Contractor Touching-distance visual inspection using any necessary access
equipment
Special As Contractor To investigate some identified defect
necessary
N/A = not applicable.
