Assessing the seismic vulnerability of masonry buildings - Seismic Risk Analysis and Management of Civil Infrastructure Systems - page 344

typology in historic centres is often the result of substantial alterations of
more traditional typologies, which may affect considerably stiffness, lateral
capacity and ductility. These results give sharper focus to the limitation and
inaccuracy of using idealised models and average curves without adequately
considering the uncertainty and variation associated with each case. A sub-
stantial variation in the drift associated with various limit states can also be
observed. In order to investigate this further, taking into account both
regional variation and different structural typologies, besides the prevalent
structural behaviour, average values of the calculated drift are presented in
Table 13.3 for comparison with the indications and limits provided by the
experimental activity and the code provisions.
For the in-plane behaviour the drift threshold values for damage limita-
tion (DL), identifi ed as fi rst cracking and change in stiffness, seems to be
lower for the numerical simulations than for the experimental ones, although
Italy II and Turkey fall within the experimental range. No provision is
offered by the Eurocode 8. For the limit state of signifi cant damage (SD),
the code provisions and the experimental data defi ne consecutive intervals,

Table 13.3 Comparison of drift values from the FaMIVE analsyis with
experimental and code reference ranges

Damage
limitation

Signifi cant
damage

Near
collapse Limit state Collapse

In-plane
prevalent
behaviour

Eurocode 8
Part 3

0.4-0.6 0.53-0.8

Experimental 0.18-0.23 0.65-0.90 1.23-1.92 2.1-2.8

Nepal 0.069 0.207 1.123 1.843

Italy I 0.023 0.069 0.990 2.547

Italy II 0.132 0.397 0.790 1.844

Turkey 0.226 0.679 1.579 1.801

Italy III 0.090 0.271 1.127 2.324

Out-of-plane
prevalent
behaviour

Eurocode 8
Part 3

0.8-1.2
( H 0 / D )

1.06-1.60
( H 0 / D )

Experimental 0.33 0.88 2.3 4.8

Nepal 0.691 1.383 1.891 2.343

Italy I 0.263 1.580 1.969 3.401

Italy II 0.460 1.380 1.714 5.562

Turkey 0.689 1.378 1.266 2.167

Italy III 0.280 0.8408 1.693 4.593

Combined
behaviour

Nepal 0.168 0.505 0.824 1.114

Italy I 0.030 0.181 1.005 1.778

Italy II 0.033 0.099 0.198 3.307

Turkey 0.102 0.305 0.724 1.201

Italy III 0.097 0.582 1.401 1.957