1
Chapter 1
Durability and service life
DOI: 10.1201/b12914-1
1.1 IntroDuctIon
For many years after the introduction of reinforced concrete as a construction material at the end of the nineteenth century, it was considered that
concrete structures were built to last without any further maintenance or
repair. Since then, however, we have learned that this unfortunately is not
the case. Serious degradation mechanisms can severely reduce the service
life of concrete structures: steel reinforcement can corrode, cement matrix
can be attacked, and even aggregates can show detrimental processes.
In many cases, the remaining service life of damaged structures can be
upgraded by a combined action of repair and maintenance. However, in
some cases demolition and replacement are the only options.
The question might be raised why ancient cultures were apparently able
to build structures which are still in good shape after several thousands
of years, while modern structures can show degradation after only a few
decades or even earlier. A marvellous example of a structure that seems to
last forever is the Roman aqueduct Pont du Gard (Figure 1.1) in the South
of France, constructed about 2000 years ago by means of blocks of limestone. Although the structure still looks marvellous and is impressive, it is
clear that even this cultural heritage is suffering from degradation mechanisms that have attacked the limestone (Figure 1.2). Furthermore, it should
also be mentioned that we all know the Pont du Gard only because it has
survived until now. Many Roman aqueducts did not survive and are long
forgotten or known to very few thanks to some remaining ruins, as nicely
illustrated by the Roman aqueduct near Fontvieille (Figure 1.3), not far
from the Pont du Gard.
Nevertheless, it is clear that ancient cultures sometimes built structures
capable of incredible performance when considering their heritage. Modern
structures seem to be more prone to degradation. Several reasons can be
listed to explain why durability issues related to concrete structures have
become more prominent during the last decades:
Chapter 1
Durability and service life
DOI: 10.1201/b12914-1
1.1 IntroDuctIon
For many years after the introduction of reinforced concrete as a construction material at the end of the nineteenth century, it was considered that
concrete structures were built to last without any further maintenance or
repair. Since then, however, we have learned that this unfortunately is not
the case. Serious degradation mechanisms can severely reduce the service
life of concrete structures: steel reinforcement can corrode, cement matrix
can be attacked, and even aggregates can show detrimental processes.
In many cases, the remaining service life of damaged structures can be
upgraded by a combined action of repair and maintenance. However, in
some cases demolition and replacement are the only options.
The question might be raised why ancient cultures were apparently able
to build structures which are still in good shape after several thousands
of years, while modern structures can show degradation after only a few
decades or even earlier. A marvellous example of a structure that seems to
last forever is the Roman aqueduct Pont du Gard (Figure 1.1) in the South
of France, constructed about 2000 years ago by means of blocks of limestone. Although the structure still looks marvellous and is impressive, it is
clear that even this cultural heritage is suffering from degradation mechanisms that have attacked the limestone (Figure 1.2). Furthermore, it should
also be mentioned that we all know the Pont du Gard only because it has
survived until now. Many Roman aqueducts did not survive and are long
forgotten or known to very few thanks to some remaining ruins, as nicely
illustrated by the Roman aqueduct near Fontvieille (Figure 1.3), not far
from the Pont du Gard.
Nevertheless, it is clear that ancient cultures sometimes built structures
capable of incredible performance when considering their heritage. Modern
structures seem to be more prone to degradation. Several reasons can be
listed to explain why durability issues related to concrete structures have
become more prominent during the last decades: