6 Damage to concrete structures
in cities like Brussels, which are completely renovated after only fifteen to
twenty years of service because of the evolution in functional office requirements (e.g. new communication methods, landscape offices instead of separate offices).
From the economical point of view, a structure can be considered as
an investment. In this case, the requirements are defined on the levels of
‘profit’ and ‘margins’. One example is the ferry boats, once linking mainland Europe with the British Island. After the completion of the Channel
tunnel, many ferry boats were taken out of the fleet. Although these boats
still perfectly complied with technical or functional requirements, from an
economical point of view they became obsolete as a substantial part of traffic shifted towards the tunnel.
The further detailed treatment in this textbook of the degradation
mechanisms in concrete structures is more linked to technical or structural
requirements. Many factors can influence the structural response of a structure as illustrated in Figure 1.5. First, based on structural requirements, the
design stage is very important. During design, the overall dimensions are
defined as well as some important construction details. The appropriate
materials have to be selected. In the case of concrete structures, this means
an appropriate mix design, based on carefully selected constituent materials. All of this should be in good agreement with the future environment of
the structure to be designed.
In the construction stage, when the structure is actually built, some
deviations can occur in comparison with the design; e.g. geometry can be
-Load/Solicitation
Environment
Maintenance or
repair
Inspection
Structural response
Comparison
Structural
requirements
Service Life
-Atmospheric parameters
-Dimensioning
Design
-Detailing
-Material selection
-Defining environment
-Strength
Construction
-Geometry (concrete cover)
-Compaction
-Coatings
-Curing
-Quality control
-Construction errors
-Agressive substances
-Temperature
-Humidity
Figure 1.5 Structural response and service life.
in cities like Brussels, which are completely renovated after only fifteen to
twenty years of service because of the evolution in functional office requirements (e.g. new communication methods, landscape offices instead of separate offices).
From the economical point of view, a structure can be considered as
an investment. In this case, the requirements are defined on the levels of
‘profit’ and ‘margins’. One example is the ferry boats, once linking mainland Europe with the British Island. After the completion of the Channel
tunnel, many ferry boats were taken out of the fleet. Although these boats
still perfectly complied with technical or functional requirements, from an
economical point of view they became obsolete as a substantial part of traffic shifted towards the tunnel.
The further detailed treatment in this textbook of the degradation
mechanisms in concrete structures is more linked to technical or structural
requirements. Many factors can influence the structural response of a structure as illustrated in Figure 1.5. First, based on structural requirements, the
design stage is very important. During design, the overall dimensions are
defined as well as some important construction details. The appropriate
materials have to be selected. In the case of concrete structures, this means
an appropriate mix design, based on carefully selected constituent materials. All of this should be in good agreement with the future environment of
the structure to be designed.
In the construction stage, when the structure is actually built, some
deviations can occur in comparison with the design; e.g. geometry can be
-Load/Solicitation
Environment
Maintenance or
repair
Inspection
Structural response
Comparison
Structural
requirements
Service Life
-Atmospheric parameters
-Dimensioning
Design
-Detailing
-Material selection
-Defining environment
-Strength
Construction
-Geometry (concrete cover)
-Compaction
-Coatings
-Curing
-Quality control
-Construction errors
-Agressive substances
-Temperature
-Humidity
Figure 1.5 Structural response and service life.