Assessing and managing the risk of earthquake-induced liquefaction to civil infrastructure - Seismic Risk Analysis and Management of Civil Infrastructure Systems - page 113

Before the earthquake

Power
distr ibu tion

Utility
facility

T an k Train

R o a d

Jetty or
port

D r y f i ne s a n d a nd s il t

R i v er

Buried utilities

Buried tanks

Fine sand and silt below
the watertable

Areas of flat and gently sloping, low lying land with high groundwater support buildings and roads, rail, buried utilities and tanks under normal conditions.

During and after the earthquake

Road

Translational failure
of slopes and undermining
of foundations and infrastructure.

Flotation of buried structures
Tanks, pipes and manholes
are buoyant in liquefied ground
and disturb or break through to
surface. Pipes rupture, causing
flooding and contamination.

Ground settlement
Ground loss due to cyclic
densification and/or
erosion of sand ejecta.

Bearing failure
Full or partial bearing failure
due to reduction in bearing
capacity, resulting in differential
settlement tilting or over-turning.

Lateral spreading
Ground movement toward
free face of river bank,
coast or man-made cutting.
Cracks along banks or cutting
extend inland, damaging
buildings and infrastructure and
partial closure of waterways.

Embankment failure
Full or partial bearing failure
of ground beneath embankment
or levee leading to translational
or rotational failure and damage
to infrastructure.

5.1 Liquefaction and its effects on infrastructure.