Handbook for Bridge Inspections - TSP2

9.2 CONCRETE ELEMENTS
207 LeakagesJ1)ampness of
Concrete
Description
This covers water seeping through cracks, leakage between prefabricated concrete elements and/or
dampness attack resulting fro m leaks or fa iled attention to detai ls. Leakages Idampncss attacks can
produce corrosion orthe reinforcement and spall ing to the covering. Leakage leads to discoloration
of the concrete (lime deposits on the surface).
Cause of Damage
* Design Fault - unsuccessful design causing leakage/dampness ..
* Material Fault - incorrect composition of the concrete can lead to porosity so that the concrete is
not water resistant.
* Construction Fault - concrete has nol been correctly vibrated which has resulted in porosity.
* Depressions cause insufficient drainage of water and the risk ofleakage and dampness attacks.
* Insufficient day· to-day operation/or maintenance.
* In-service damage, e.g. secondary damage.
Degree of Damage/Consequences
The degree of damage should be selected depending on the age of the bridge, the extent of the lea·
kage/dampness impact and the speed at which other damage can develop.
Leakage/dampness impact can affect maintenance costs and/or traffic safety in so far as icicles and
icy road surfaces can form in winter.
Conditions which Trigger Maintenance Measures
Measures should be taken to stop leakage/dampness impact before the risk arises of other damage
develop ing such as corrosion oflhe re inforcement and spalling. If, fo r example, reduced traffic
safety or icy sections can result from leakage/dampness impact, then immediate action must be
taken.
Procedures
* Sealing, injection fill ing
* Alteration to the water drainage system
* Mechanical repairs to the concrete
* Installation of new waterproofing layer on the bridge deck.
164 Handbook for Bri dge Inspect ions