Assessing the seismic vulnerability of masonry buildings - Seismic Risk Analysis and Management of Civil Infrastructure Systems - page 348

Figure 13.7 shows the set of fragility curves obtained for the two limit
states of DL and SD as computed for three Italian sites considering the
three types of structural behaviour separately. It should be noted that while
the DL state shows in all cases the lognormal distribution is suitable, the
same cannot be said for the SD limit state which shows a narrow range of
values for all three classes of mechanism. As, once a structural typology is
assigned, values of the mechanical characteristics are the same across the
three cases, while the structural details are accounted for directly in the
three classes of mechanisms, the variability observed on a same diagram

LS damage limitation in-plane mechanism

1

0.9

Nocera Umbra
L

0.8

Aquila
Serravalle

′

0.7
0.6
0.5
0.4
0.3
0.2
0.1

0

0.0001 0.001 0.01 0.1 1 10 100

Displacement (cm)

(a)

LS significant damage in-plane mechanism

1

0.9

Nocera Umbra
L

0.8

Aquila
Serravalle

′

0.7
0.6
0.5
0.4
0.3
0.2
0.1
0

0.001 0.01 0.1 1 10 100

Displacement (cm)

(b)

13.7 Fragility distribution for limit states (LS) of damage limitation
(DL) and signifi cant damage (SD) for the three classes of collapse
mechanisms for three different Italian sites.