Seismic risk analysis and management of civil infrastructure systems: an overview - Seismic Risk Analysis and Management of Civil Infrastructure Systems - page 161

listic seismic hazard analysis (Budnitz et al. 1997; 1998), which is linked with
nuclear seismic risk assessment) and Cooke's method (Cooke 1991).
Caterino et al. (2009), for example, have illustrated MCDM-based retrofi t
selection using decision-support software TOPSIS, ELECTRE, MAUT,
PROMETHEE, etc. These MCDM techniques require generation of rela-
tive weights between two criteria. In this chapter, the example provided in
Caterino et al. (2009) is extended into a decision making framework without
consideration of weights (e.g. Laplace criterion, Maximin criterion, Hurwicz
criterion, etc.).
The structure considered in the application is a three-storey RC structure
built at the European Laboratory for Structural Assessment (ELSA) of the
Joint Research Center (JRC) in Ispra, Italy (Caterino et al. 2009), which is
representative of pre-seismic code constructions in southern Europe. A
total of fi ve seismic resistance upgrading options are considered, three of
those aiming at seismic capacity enhancement (A 1 , A 2 , A 3 ), while the last
two providing seismic demand reduction (A 4 , A 5 ). The fi ve retrofi tting
options are:

1. A 1 : confi nement by glass fi ber reinforced plastic of columns and joints
(increases the building displacement capacity).
2. A 2 : addition of steel braces (provides a global strength and stiffness
enhancement).
3. A 3 : concrete jacketing of selected columns (partial but simultaneous
enhancement of strength and ductility).
4. A 4 : base isolation of the structure (reduction of the seismic forces).
5. A 5 : installing four viscous dampers at the fi rst story of the building
(attenuates the seismic demand).

Each of the fi ve options is evaluated based on eight criteria x ij , where i
represents the option used and j represents the criterion (see Table 6.5).
Results of the fi ve options with respect to the eight evaluation criteria are
provided in Table 6.6 (adopted from Caterino et al. , 2009).

Table 6.5 Description of eight evaluation criteria

Criterion Application

C 1 Installation cost

C 2 Maintenance cost

C 3 Duration of work/disruption of use

C 4 Functional compatibility

C 5 Skilled labor requirement/needed technology level

C 6 Signifi cance of the needed intervention at foundations

C 7 Signifi cant damage risk

C 8 Damage limitation risk