Handbook for Bridge Inspections - TSP2

When an underwater main inspection has revealed the need for
major repairs or has not been adequate enough to ascertain the
nature of any damage, its consequences, scope or cause, then more
comprehensive measurements and materials testing may require to
be carried oul.
The inspection should be undertaken by di vers who must possess
the necessary quali fications and approval in accordance with
public regulations.
Refer to Chapter 8.2 for making reports of Underwater Major
Inspections.
6.6.2 Visual Inspections
These should be made at close quarters, i.e. the diver should be
able to touch the different bri dge elements.
Before a visual inspection can be conducted all fo rm work and
overgrowth remaining should first be removed from a large
enough area so as to provide a sufficien tl y clear overview of the
condition of the fou ndat ions. The anti-rust protection does not
have to be taken away in order to remove absolutely all the formwork.
Ice Sheath ing does not require to be removed either.
Overgrowth can be removed either with a barking spade orland a
high pressure hose.
In accordancc with Chapter 2.1.6 any damage should be recorded
on fold-out drawings of the foundations.
The foundations should be inspected from the riverbed upwards to
the water surface and include tida l areas. Any damage should be
photographed and described accurately.
Each element is to be inspected for damage, defects and faults as
detailed below. Refer 10 Chapter 9, Damage Eva luation Catalogue.
Underwater (; round
Concrete Elements
'" Erosion and lor undermining of foundations
'" Damming up caused by loose material, wood, branches whi ch
can reduce the through flow of water.
'" Damage to free-standing piles
'" Damage to protection agai nst erosion
'" Settlement/movement of abutment pi ers, piers etc.
'" Hair cracks and cracks.
'" Reinforcement with little or damaged cover.
'" Weathering due, for example, to frost, strain caused by weather
cond it ions etc. especially in areas subject to tides.
'" Depressions/holes in castings or badly cast joints.
'" Corrosion of the re inforcement or spalling.
'" Areas subject to wash out.
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Handbook for Bridge Inspect ions