Assessing and managing the risk of earthquake-induced liquefaction to civil infrastructure - Seismic Risk Analysis and Management of Civil Infrastructure Systems - page 129

5.9 Damage to port structures and warehouses due to liquefaction-
induced lateral spreading following the Haiti earthquake of January
2010 (courtesy EEFIT, UK).
Buildings respond very differently to uniform settlement, differential
settlement and differential lateral movement; the latter having the most
damaging potential. Buildings on piled foundations have signifi cantly higher
resistance than those on shallow foundations, and buildings on stiff shallow
raft foundations are less vulnerable than those on individual pad footings.
Structural system and construction quality are also contributory factors.
5.4.4 Methods of assessment
For a typical site-specifi c design, a preferred approach for zones of poten-
tially liquefi able material is often to mitigate the liquefaction through
design (e.g. ground improvement or avoidance, or for structures, use of piled
foundations). However, for a risk-based approach, it is important to evalu-
ate the impact of the liquefaction on the infrastructure system, in order to
make a risk-informed decision as to whether the liquefaction should be
mitigated, or whether the risk is acceptable with no additional measures.
For a linear infrastructure system particularly, avoidance of liquefaction is
diffi cult, and mitigation will be costly.